Biostimulants occupy a curious regulatory and scientific niche. Unlike fertilizers, they are not defined primarily by the nutrients they deliver, and unlike pesticides, they do not kill pests directly. Instead, as the review emphasizes, they regulate plant metabolism. The authors stress that plant-derived extracts almost never act through a single active constituent. A typical extract is a dense biochemical cocktail containing phytohormone-like compounds, antioxidants, osmoprotectants, phenolics, oligosaccharides, fatty acids, proteins and peptides. This compositional complexity is not a nuisance to be purified away; it is the point. Multiple molecules converge on multiple signaling pathways simultaneously, producing effects that no isolated compound could replicate.

The mechanistic core of the review centers on hormone signaling. Extracts modulate the major stress hormones of plants, including abscisic acid, salicylic acid, jasmonic acid and ethylene, which together orchestrate everything from stomatal closure during drought to the activation of pathogen defenses. Transcriptomic studies cited in the review show that treatment with extracts such as those from Ascophyllum nodosum, a brown seaweed long used in commercial biostimulant products, upregulates stress-responsive genes in crops ranging from Arabidopsis to soybean and tomato. In effect, the extracts behave like a training signal, priming the plant’s own defense machinery so that when real stress arrives, the response is faster and stronger.

Beyond hormones, the review catalogues a suite of physiological adjustments that extracts induce. Treated plants accumulate more osmolytes, small compatible solutes such as proline and glycinebetaine that help cells retain water and maintain turgor under drought or salt stress. Antioxidant defenses are strengthened, allowing plants to neutralize the reactive oxygen species that spike when photosynthesis is disrupted. Ionic homeostasis is restored, helping roots exclude sodium or compartmentalize it away from sensitive metabolic machinery. Perhaps most intriguingly, the review highlights evidence that extracts regulate water transport through aquaporins, the membrane channels that control the flow of water across plant cells, offering a direct physical route to improved drought tolerance.

The review also draws attention to the rhizosphere, the teeming microbial zone around plant roots. Extracts influence rhizosphere interactions and microbiome dynamics, according to the authors, thereby improving nutrient acquisition and systemic resilience. Studies combining seaweed extracts with plant growth-promoting rhizobacteria in wheat, rice, onion and cucumber report synergistic effects on growth and yield that neither partner achieves alone. This reframes biostimulants not merely as foliar tonics but as ecosystem engineers that reshape the underground communities on which crop nutrition depends, a perspective increasingly central to soil health science.

Case studies across stress types give the review its agronomic weight. Under drought, moringa leaf extract has improved rice yield and grain quality through enhanced antioxidant activity, while seaweed extract has bolstered sugarcane drought resistance by modulating root architecture and soil properties. Under salinity, extracts from Ascophyllum, willow, licorice root and grape seed have each improved photosynthetic stability and ion balance in crops such as tomato, maize, pea and faba bean. Heat stress studies in wheat and maize report that moringa and sorghum water extracts preserve photosynthetic pigments, while cold stress trials in barley and tomato show brown seaweed extracts triggering cold-acclimation gene expression. Biotic stress studies add another layer, with laminarin from brown algae eliciting grapevine defenses against downy mildew and botrytis, and seaweed extracts reducing fungal disease on carrot foliage.

Application strategy emerges as a critical variable. The review distinguishes between foliar sprays, seed priming and soil drenching, noting that dose, timing and method can determine whether an extract helps or does nothing at all. Seed priming with moringa leaf extract has reduced chilling injury in spring maize and improved rice seedling establishment under water deficit, while foliar application has induced terminal heat tolerance in quinoa. Processing matters too: the review notes that extraction methods, from mechanical disruption to enzyme-assisted techniques, shape which phytochemicals survive into the final product, and that even storage temperature can alter cytokinin and auxin concentrations in seaweed concentrates.

The most forward-looking section concerns nanotechnology. Plant-mediated nanoparticles and nano-formulations, the authors report, improve the stability, delivery efficiency and bioavailability of bioactive phytochemicals. Examples span the emerging literature: Sargassum-synthesized zinc oxide nanoparticles inducing salt tolerance in maize, neem-mediated silver nanoparticles improving drought-stressed soybean growth, Spirulina-derived carbon dots used for seed nanopriming in rice, and nano-encapsulated biostimulants enhancing photosynthetic efficiency in heat-stressed peppers. Nano-encapsulation can also protect volatile or easily degraded compounds, such as essential oils, from rapid environmental loss. The authors caution, implicitly, that nanoparticle-plant interactions, including uptake, transport and potential toxicity, remain active areas of investigation, and that environmental implications must be weighed alongside agronomic gains.

What emerges from the synthesis is a picture of plant-derived biostimulants as systems-level interventions rather than simple inputs. A single seaweed extract may simultaneously adjust hormone signaling, boost antioxidant capacity, alter root growth, feed beneficial microbes and prime defense genes, all without introducing novel genetic material or synthetic chemistry. For farmers facing increasingly erratic rainfall, salinizing soils and heat waves, this profile is attractive precisely because it works with the plant’s existing physiology rather than overriding it. The review’s case studies consistently report improvements in photosynthetic stability, stress tolerance and yield under optimized application strategies, suggesting that the gap between laboratory promise and field performance is narrowing.

The authors close with a research agenda that reads like a roadmap for the next decade of the field. Future progress, they argue, will require integrating multi-omics approaches, combining transcriptomics, metabolomics and proteomics to resolve exactly which molecules in a complex extract drive which responses, alongside microbiome profiling to track how extracts reshape root communities over time, and precision nanotechnology to deliver the right bioactive to the right tissue at the right moment. If that integration succeeds, the humble plant extract, long dismissed as folk agronomy, could become a cornerstone of sustainable agriculture, helping crops weather a climate that is growing less forgiving by the season.

Subject of Research: Mechanisms of plant-derived biostimulants in enhancing crop stress tolerance and sustainable agriculture

Article Title: Mechanistic insights into plant-derived biostimulants for sustainable agriculture and stress tolerance

Article References: Mishra, A., Bhatt, U., & Soni, V. (2026). Mechanistic insights into plant-derived biostimulants for sustainable agriculture and stress tolerance. Plant Biosystems, 160(6), Article 295. https://doi.org/10.1007/s44473-026-00314-2

Image Credits: AI Generated

DOI: 10.1007/s44473-026-00314-2

Keywords: biostimulants, plant extracts, seaweed extracts, abiotic stress, drought tolerance, salinity stress, phytohormones, antioxidants, nanotechnology, soil microbiome, sustainable agriculture, moringa oleifera

Camellia oleifera is one of China’s most important woody oil crops, cultivated extensively for its seeds, which yield high-quality edible oil. However, like many crops, its growth and productivity are frequently constrained by drought stress, a challenge that is becoming increasingly severe as climate patterns shift. The REVEILLE family of genes, which includes RVE1, plays crucial roles in plant stress responses, yet their functions in C. oleifera remained largely unexplored before this study. The researchers set out to clone the RVE1 homolog from C. oleifera and investigate whether it contributes to drought tolerance, a question with significant implications for the genetic improvement of woody oil crops.

The team began by cloning CoRVE1 and analyzing its expression patterns under various stress conditions. Expression analyses revealed that CoRVE1 was significantly induced by drought, salt, and abscisic acid (ABA) treatments, indicating that the gene responds to multiple stress signals. ABA is a key plant hormone involved in stress responses, and its involvement suggests that CoRVE1 may be integrated into the ABA-dependent stress signaling pathway. The gene also displayed tissue-specific expression patterns, providing clues about where in the plant it exerts its effects. These findings positioned CoRVE1 as a promising candidate for functional characterization through heterologous overexpression.

To test the gene’s function directly, the researchers overexpressed CoRVE1 in Arabidopsis thaliana, a widely used model plant that allows rapid genetic analysis. The results were striking. Two overexpression lines showed markedly enhanced drought tolerance, with survival rates of 84% and 86% after drought treatment, compared with only 20% in wild-type plants. In detached-leaf water-loss assays, the transgenic lines lost water at a rate of 7.6% and 7.2% after 200 minutes, compared with 9% in the wild type, indicating improved water retention. The overexpression lines also promoted plant growth under stress conditions, suggesting that CoRVE1 does not simply trade growth for survival but supports both.

Physiological analyses provided mechanistic insight into how CoRVE1 enhances drought tolerance. The transgenic lines showed enhanced antioxidant capacity, with increased activities of superoxide dismutase (SOD), peroxidase, and catalase. After 10 days of drought, SOD activity increased by 84.6–85.7% in the transgenic lines, compared with 37.6% in the wild type. These enzymes neutralize reactive oxygen species, which accumulate during drought stress and damage cellular components. Consistent with this protective effect, malondialdehyde accumulation, a marker of oxidative damage to membranes, was reduced by 17–18% under drought stress in the overexpression lines. This reduction indicates that CoRVE1-overexpressing plants suffer less membrane damage when water is scarce.

Beyond antioxidant defense, the transgenic lines showed improved osmotic adjustment, reflected by altered accumulation of proline, soluble sugars, and soluble proteins. Osmotic adjustment is a critical drought-response mechanism in which plants accumulate compatible solutes to maintain cellular water content and turgor pressure under water deficit. Proline, in particular, is a well-known osmoprotectant that stabilizes proteins and membranes while contributing to osmotic balance. The altered accumulation of these solutes in CoRVE1-overexpressing plants suggests that the gene enhances the plant’s ability to maintain physiological function during drought by improving osmotic regulation at the cellular level.

At the molecular level, the researchers found that several drought-responsive genes were significantly upregulated in CoRVE1-overexpressing plants. These included RD29A, RD22, KIN1, COR15A/B, LEA14, LEA76, and CER3, as well as NCED3, a gene involved in ABA biosynthesis. RD29A and RD22 are classic drought-inducible genes whose activation is a hallmark of the plant drought response. LEA proteins, encoded by LEA14 and LEA76, protect cellular structures during dehydration. NCED3 is a rate-limiting enzyme in ABA biosynthesis, and its upregulation suggests that CoRVE1 may enhance ABA accumulation, thereby amplifying the ABA-dependent stress signaling cascade. The coordinated upregulation of this gene network indicates that CoRVE1 acts upstream of multiple drought-response pathways rather than on a single target.

The findings suggest that CoRVE1 positively contributes to drought tolerance by enhancing antioxidant defense and osmotic adjustment and is associated with the upregulation of stress-related genes. This study provides new insights into the drought response of C. oleifera and identifies CoRVE1 as a potential candidate gene for further functional study and genetic improvement of drought resistance in woody oil crops. The research was funded by the Hunan Key Technologies Research and Development Program and the Hunan Provincial Forestry Science and Technology Research and Innovation Fund Project, reflecting regional investment in oil-tea improvement.

For a crop that anchors rural economies across southern China, the identification of a transcription factor that can be engineered to boost drought survival represents a meaningful step toward climate-resilient oil-tea plantations. While the current work was performed in a heterologous system, the strong physiological and molecular evidence positions CoRVE1 as a compelling target for future breeding programs. As drought intensifies across agricultural regions worldwide, genes like CoRVE1 may prove essential tools in the effort to sustain productivity of woody oil crops under increasingly unpredictable conditions.

Subject of Research: Plant Biology

Article Title: Overexpression of Camellia oleifera CoRVE1 enhances drought tolerance in transgenic Arabidopsis thaliana

Article References: Ma, X., He, Z., Yang, D., Zhang, Y., Xun, C., Ma, Y., Wang, R., & Chen, Y. (2026). Overexpression of Camellia oleifera CoRVE1 enhances drought tolerance in transgenic Arabidopsis thaliana. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09866-z

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09866-z

Keywords: drought tolerance, CoRVE1, Camellia oleifera, transcription factor, Arabidopsis thaliana, ABA signaling, antioxidant defense, osmotic adjustment, oil-tea, BMC Plant Biology, Overexpression, Camellia

The core problem the review identifies is what researchers call the breeder’s dilemma. Conventional forage breeding has historically prioritized yield, stress tolerance, and pest resistance, while traits that matter enormously to ruminant nutrition, such as digestibility, crude protein content, and the reduction of anti-nutritional compounds, have received far less attention. The result is a generation of improved cultivars that perform beautifully in agronomic trials yet fail to deliver meaningful gains in animal productivity. Improved cereal and forage varieties often produce more biomass but retain high lignin or phytate levels that limit how much energy and protein livestock can actually extract from them.

The consequences of this mismatch are most visible during the dry season. Studies from Tanzania and Ethiopia cited in the review show that crude protein and metabolizable energy levels in available forages can drop by 20 to 28 percent when the rains fail, driving milk production down by as much as 40 percent. In Nigeria, ruminant systems face acute forage scarcity during dry months, forcing farmers to rely on low-nutrient crop residues or expensive commercial supplements. These seasonal feed gaps are compounded by drought-induced pasture loss, livestock mortality, and declining soil fertility, undermining household food security and the long-term viability of mixed farms across the tropics.

Forages are not a minor input in these systems. Grasses and legumes supply more than 90 percent of the feed energy consumed by herbivorous livestock worldwide, effectively converting non-human-edible biomass into high-quality animal protein. The review catalogs the workhorses of tropical pasture science: Brachiaria grasses such as the Marandu, Piata, and Xaraes cultivars, prized for drought tolerance and persistence; Guinea grass, which offers high biomass but demands fertile soils; and Napier grass, a staple of cut-and-carry systems despite its vulnerability to stunt and smut diseases. On the legume side, species like Stylosanthes, Leucaena leucocephala, Desmodium, and Lablab purpureus boost crude protein in forage mixtures and fix nitrogen biologically, enriching the soil in the process.

The nutritional chemistry of these plants tells a striking story. Many tropical grasses, including Urochloa brizantha and the Urochloa hybrid Cayman, deliver crude protein concentrations of just 68 to 77 grams per kilogram of dry matter, below the threshold needed for efficient rumen microbial function. Legumes such as Leucaena diversifolia and Canavalia brasiliensis reach 195 to 256 grams per kilogram, while also contributing more metabolizable energy and lowering neutral detergent fiber and acid detergent lignin, both of which improve digestibility. Mineral deficits in calcium, phosphorus, and magnesium are common in dry-season tropical grasses and must be corrected through supplementation or by integrating mineral-rich legumes into pastures.

But legumes come with their own chemical complications. Leucaena diversifolia can carry condensed tannin concentrations of up to 47 grams per kilogram of dry matter, along with phenolics that bind proteins and reduce digestibility. The review notes that moderate tannin levels can actually be beneficial, slowing ruminal protein degradation and reducing nitrogen losses, but excessive amounts depress intake and nutrient absorption. Palatability adds another layer of complexity: birdsfoot trefoil, for example, is often less palatable than lucerne or white clover, and rapidly degradable legume proteins can cause ruminal ammonia accumulation and environmental nitrogen losses if not balanced with sufficient dietary energy.

On the resilience side, the review details the physiological traits that separate drought survivors from casualties. Deep and dense root systems allow plants like cocksfoot and tall fescue to tap subsoil moisture; deep-rooting tall fescue cultivars such as Flecha and Centurion demonstrate improved survival by accessing deeper water reserves. Osmotic adjustment, the accumulation of compatible solutes like proline, glycine betaine, and trehalose, maintains cell turgor and stabilizes membranes and proteins during water stress. Transpiration efficiency matters too, and C4 grasses including several Brachiaria cultivars hold an inherent advantage thanks to their photosynthetic pathway and reduced stomatal conductance. The cocksfoot cultivar Kasbah takes an even more dramatic approach, entering complete summer dormancy to survive prolonged drought, though at the cost of relatively low water-use efficiency during active growth.

The breeding toolkit itself is evolving, though unevenly. Conventional methods remain the cornerstone: mass selection, recurrent selection, and hybridization have produced landmark cultivars such as Marandu in Brazil, which combined high biomass yield with adaptation to acidic soils. Yet these approaches are slow, typically requiring 10 to 15 years to release a new cultivar, and apomictic grasses that propagate clonally through seeds complicate genetic recombination. Modern molecular tools promise acceleration but face real barriers. Marker-assisted selection has underperformed in forages because traits like digestibility and drought tolerance are polygenic and expensive to screen for. Genomic selection and genome-wide association studies have transformed maize, wheat, and dairy cattle breeding but lag in forage crops, where large training populations are required and commercial investment is thin. CRISPR gene editing offers tantalizing prospects for tailoring lignin and tannin levels, but regulatory restrictions and public acceptance remain significant hurdles.

Perhaps the most compelling section of the review addresses what happens when the two disciplines genuinely collaborate. Australia’s EverCrop initiative provides a working model, integrating crop improvement with animal performance trials from the design stage of breeding programs. Feed evaluation trials, including in vitro digestibility assays and animal model studies measuring intake, growth, reproduction, and feed efficiency, should become integral to selection pipelines rather than afterthoughts. Case examples show the payoff: forage sorghum delivers both biomass and energy density for dry-season feeding, while Desmodium intortum grown with Napier grass and Brachiaria improves crude protein, metabolizable energy, feed intake, and animal productivity while simultaneously enriching soil through nitrogen fixation. Trials with different ryegrass cultivars similarly demonstrate that evaluating plant and animal outcomes together identifies genuinely superior forages.

The review is candid about the obstacles that go beyond the laboratory. Adoption of improved forages in sub-Saharan Africa has been hampered by weak seed markets, high establishment costs, and limited extension services, in sharp contrast to Brazil, where strong seed systems and government-private sector partnerships enabled large-scale uptake of Brachiaria cultivars and measurable gains in beef productivity. Genetic trade-offs also persist: breeding for drought tolerance often raises lignin content or delays maturity, both of which reduce digestibility, while selecting for high protein or reduced fiber can compromise persistence and pest resistance. The authors call for holistic breeding programs with embedded nutritional testing, integrated forage innovation hubs connecting research institutions, seed companies, and extension networks, and policies that fund integrative research and guarantee seed availability. They also acknowledge the limitations of their own evidence base, noting that most cultivar evaluations remain confined to controlled experiments and that socioeconomic factors such as labor availability, gender roles, and market incentives are poorly integrated into breeding priorities. The message is clear: resilient, nutritious forages exist on the drawing board, but turning them into farm-level transformation will require sustained investment, participatory research, and delivery systems that finally connect plant science to the animals and farmers who depend on it.

Subject of Research: Integrating plant breeding and animal nutrition to develop drought-tolerant, high-nutrient forage grasses and legumes for sustainable ruminant livestock production

Article Title: Synergizing plant breeding and animal nutrition: A review on the development of drought-tolerant and high-nutrient forage grasses and legumes

Article References: Adepoju, S. A., & Faniyi, T. O. (2025). Synergizing plant breeding and animal nutrition: A review on the development of drought-tolerant and high-nutrient forage grasses and legumes. Innovations in Agriculture, 8, 1-10. https://doi.org/10.3897/ia.2025.163461

Image Credits: AI Generated

DOI: 10.3897/ia.2025.163461

Keywords: forage breeding, drought tolerance, ruminant nutrition, forage legumes, forage grasses, crude protein, digestibility, sub-Saharan Africa, livestock productivity, seed systems, genomic selection, climate resilience

The central insight of the review is that stress tolerance in a grafted plant emerges from the coordinated action of four signalling subsystems that couple the rootstock to the scion. The first is hydraulic regulation, the management of water flow through the vascular system. The second is ion homeostasis, the selective exclusion or compartmentalization of toxic ions such as sodium and chloride. The third is hormonal and mobile molecular signalling, in which chemical messengers travel from root to shoot and back. The fourth is graft-union integrity, the structural and functional quality of the junction where rootstock and scion meet. Each of these subsystems can be measured, manipulated and, increasingly, bred for. The authors emphasize that previous reviews have treated rootstock breeding, stress physiology, rootstock diversity and long-distance signalling as separate topics, and that an integrated cross-crop synthesis linking causal mechanisms with practical breeding criteria has been lacking.

One of the most striking findings concerns the role of water transport proteins known as aquaporins. In the experimentally separated systems reviewed, measured aquaporin activity, rather than the abundance of aquaporin transcripts, showed a stronger correspondence with hydraulic performance. This distinction matters because gene expression data are far easier to collect than direct measurements of protein function, and many breeding programs have relied on transcript-based markers. The review suggests that rootstocks with high aquaporin transcript levels do not necessarily conduct water more efficiently, and that phenotyping pipelines should prioritize direct flux and conductance measurements over gene expression readouts when the goal is to predict hydraulic performance under stress.

The review also reframes long-standing debates about abscisic acid, the hormone most closely associated with plant drought responses. Root abscisic acid biosynthesis contributes to rootstock-conferred drought tolerance in the systems examined, but the authors caution that leaf abscisic acid concentrations must always be interpreted against the plant’s actual water status. A scion may accumulate abscisic acid simply because it is dehydrated, not because the rootstock has signalled it to close its stomata preemptively. To resolve this ambiguity, the authors highlight the value of hormone ratios rather than single-hormone measurements. In the systems tested, ratios such as cytokinin to ACC and ACC to abscisic acid proved informative and merit systematic evaluation as breeding criteria. This shift from concentration-based to ratio-based phenotyping represents a conceptual advance in how rootstock effects on scion physiology are quantified.

Ion homeostasis emerges as another critical axis of rootstock-mediated tolerance, and the review identifies a persistent source of confusion in the literature. Sodium-driven toxicity and chloride-driven toxicity are not interchangeable phenomena, yet studies often conflate them. Rootstocks differ in their capacity to exclude each ion at the root level, to restrict transport to the shoot, and to compartmentalize ions within tissues. The authors argue that distinguishing sodium-specific from chloride-specific mechanisms is essential for breeding rootstocks suited to particular salinity profiles, whether those involve coastal salt spray, irrigation water high in sodium salts, or soils dominated by chloride accumulations. This reframing turns a methodological inconsistency into a testable breeding target.

A fourth contradiction addressed in the review concerns the widely discussed trade-off between dwarfing and drought tolerance. Many commercial rootstocks that reduce scion vigor, a desirable trait for high-density orchards, have been assumed to compromise drought performance. The authors treat this proposed trade-off not as an established fact but as a hypothesis requiring rigorous testing across genetic backgrounds and environments. If the trade-off proves conditional rather than universal, it opens the door to breeding compact rootstocks that maintain hydraulic resilience under water limitation, a combination that would be transformative for intensive fruit production in water-scarce regions.

Methodologically, the review prioritizes studies that establish causal links rather than mere correlations. Reciprocal grafting onto biosynthetic or transport mutants, direct flux and conductance measurement, isotope tracing and map-based cloning are highlighted as the gold standards for demonstrating that a rootstock trait actually causes a scion response. This evidentiary bar is important because the rootstock-scion interaction is notoriously difficult to disentangle. A rootstock may alter scion behavior through water supply, through hormonal signals, through mobile RNAs or small peptides, or through changes in the root microbiome, and only experimental designs that separate these channels can identify the true mechanism. The authors note that transport has emerged as an important limiting step in several of the systems they examined, underscoring the value of measuring actual movement of water and ions rather than inferring it from gene expression.

Perhaps the most consequential message for breeders is a note of caution about cross-crop generalization. The core molecular toolkits that plants use to respond to abiotic stress are conserved across lineages, but the review finds that they are deployed divergently by different fruit crop groups. This means that molecular markers validated in one crop, such as apple or grapevine, may not transfer directly to other crops such as citrus, stone fruits or tropical species without further validation. The authors call for ideotype-driven breeding pipelines in which the desired rootstock phenotype is defined first, in terms of hydraulic conductance, ion exclusion capacity, hormone signalling profiles and graft-union performance, and markers are then validated within each target crop rather than imported wholesale from distant relatives.

The review concludes with a forward-looking agenda that emphasizes flux-based, ratio-based and activity-based phenotyping alongside the more traditional concentration-based, single-hormone and transcript-based criteria. It also draws attention to a significant gap in the literature: tropical and subtropical fruit crops remain under-resourced in rootstock research relative to temperate species, despite facing some of the most acute climate pressures. As droughts lengthen, saline intrusion spreads and temperature extremes intensify, the ability to swap the underground half of a fruit tree while preserving the fruit cultivar above represents a uniquely flexible adaptation strategy. The authors argue that with better mechanistic understanding and more rigorous phenotyping, precision rootstock breeding could deliver climate-resilient orchards faster than any other single intervention in perennial fruit crop improvement.

Subject of Research: Rootstock-mediated abiotic stress tolerance mechanisms and precision breeding in fruit crops

Article Title: Rootstock-mediated abiotic stress tolerance in fruit crops: physiological mechanisms, long-distance hormonal and molecular signalling, and implications for precision rootstock breeding

Article References: Jayavigneshwaran, M. K., Dishri, M., Das, U., & Poonguzhali, S. (2026). Rootstock-mediated abiotic stress tolerance in fruit crops: physiological mechanisms, long-distance hormonal and molecular signalling, and implications for precision rootstock breeding. Frontiers in Horticulture, 5, Article 1988535. https://doi.org/10.3389/fhort.2026.1988535

Image Credits: AI Generated

DOI: 10.3389/fhort.2026.1988535

Keywords: rootstock, abiotic stress, drought tolerance, salinity, fruit crops, grafting, plant hormones, aquaporins, precision breeding, climate resilience, Rootstock-mediated, abiotic

The study was structured in two phases. In Phase 1, all 400 spring wheat genotypes were evaluated at the seedling stage under three moisture regimes: 100%, 70%, and 40% field capacity. A completely randomized design with three replicate pots per genotype-treatment combination was used, and ten morpho-physiological traits were recorded for each line. This seedling-stage screening served as the first filter, allowing researchers to identify genotypes that maintained growth under reduced water availability before committing resources to more expensive and time-consuming field trials.

The results of Phase 1 revealed the physiological toll that drought takes on young wheat plants. Mean seedling length declined from 40.0 cm under full moisture to approximately 29 cm under drought stress, a reduction that was statistically significant at P ≤ 0.01. Perhaps more telling was the response of proline content, an osmoprotectant that plants accumulate under water stress to protect cellular structures. Proline levels increased approximately 5.5-fold under drought conditions, also significant at P ≤ 0.01. Interestingly, no statistically significant difference was observed between the two drought levels for the growth traits, suggesting that once moisture dropped below a certain threshold, additional stress did not further impair seedling growth in a measurable way.

To make sense of the ten measured traits across 400 genotypes and three moisture regimes, the researchers turned to principal component analysis, a multivariate statistical technique that condenses correlated variables into independent axes of variation. The first two principal components jointly explained approximately 40% of the seedling-stage variation across all moisture regimes, while five components were required to explain more than 70%. This relatively even distribution of variance across multiple components indicated that drought adaptation at the seedling stage is not governed by a single dominant trait but rather by a combination of independent morpho-physiological characteristics.

Building on this multivariate framework, the team developed an integrated ranking system that combined standardized trait means, PC1 and PC2 scores, and hierarchical-cluster membership. Rather than relying on any single metric, this approach synthesized information from multiple dimensions of the phenotypic data to produce a holistic assessment of each genotype’s drought performance. From this ranking, 105 lines were advanced to Phase 2 field evaluation, representing roughly a quarter of the original pool. This sequential narrowing strategy exemplifies how controlled-environment screening can serve as an efficient pre-filter for field trials, reducing the logistical burden while preserving phenotypic diversity.

Phase 2 subjected the 105 selected lines to field-stage drought treatments at two critical developmental stages: drought at anthesis and drought at grain development, alongside a full-irrigation control. These stages are particularly vulnerable points in the wheat life cycle, as water stress during flowering can reduce grain set while stress during grain filling can diminish kernel weight and overall yield. The field evaluation provided a real-world test of whether seedling-stage tolerance translates into adult-plant drought resilience, a question that has long challenged plant breeders.

The field-stage results revealed a striking reorganization of the phenotypic structure under stress. Under full irrigation, the first principal component accounted for 60.96% of the phenotypic variation, indicating that a single dominant axis governed growth differences among genotypes in the absence of stress. However, under drought at anthesis, PC1’s contribution dropped to 22.47%, and under drought at grain development it fell to 30.26%. This redistribution of phenotypic variance across a larger number of independent axes under stress suggests that drought adaptation in adult wheat plants involves multiple independent traits rather than a single dominant characteristic, and that the genetic architecture of drought response differs fundamentally between well-watered and stressed conditions.

This stage-specific reorganization of the phenotypic structure carries important implications for breeding programmes. The authors caution against reliance on single-trait or single-stage selection, arguing that the multi-trait, multi-stage nature of drought adaptation demands a more comprehensive approach. A genotype that performs well at the seedling stage may not maintain that advantage under field conditions, and traits that correlate with yield under full irrigation may become decoupled under water stress. The pronounced shift in how phenotypic variance is distributed between seedling and field stages, and between different drought timing treatments in the field, underscores the complexity of drought as a breeding target.

The 105 lines identified through this sequential multivariate profiling represent a phenotypically diverse subset of Pakistani wheat germplasm suitable as parental material for a Line × Tester crossing programme aimed at drought resilience. The Line × Tester mating design is a well-established quantitative genetics approach that allows breeders to estimate combining ability and heterosis, providing insights into which parental combinations are most likely to produce superior drought-tolerant offspring. By ensuring that the selected parents span a range of phenotypic profiles rather than clustering around a single trait optimum, the multivariate approach maximizes the genetic diversity available for recombination in the breeding programme.

The germplasm used in this study was provided by the Pakistan Agricultural Research Council, the Wheat Research Institute in Faisalabad, and the Regional Agricultural Research Institute in Bahawalpur, reflecting a collaborative effort to harness national genetic resources for climate adaptation. The research was supported by the Recep Tayyip Erdoğan University Development Foundation, and the authors acknowledge TÜBITAK for granting a fellowship under the 2221 Sabbatical Scientist Support Programme. As drought intensifies across semi-arid wheat-growing regions from South Asia to the Middle East and beyond, the sequential multivariate profiling strategy demonstrated in this study offers a practical template for other breeding programmes seeking to identify climate-resilient germplasm from large collections. The work highlights that drought tolerance is not a single destination but a journey through multiple developmental stages, each with its own set of adaptive requirements, and that successful breeding for drought resilience must embrace this complexity rather than oversimplify it.

Subject of Research: Drought tolerance screening of bread wheat germplasm using multivariate phenotypic profiling

Article Title: Multivariate phenotypic profiling identifies drought-tolerant bread wheat germplasm through sequential seedling and field-stage screening

Article References: Zeeshan, M., Alam Khan, M., Ahmad, I., Normat Saydullayevich, X., Azhar Nadeem, M., Gou, J.-Y., Shehzad Baloch, F., & Tanveer Altaf, M. (2026). Multivariate phenotypic profiling identifies drought-tolerant bread wheat germplasm through sequential seedling and field-stage screening. BMC Plant Biology. https://doi.org/10.1186/s12870-026-10121-8

Image Credits: AI Generated

DOI: 10.1186/s12870-026-10121-8

Keywords: bread wheat, drought tolerance, germplasm screening, principal component analysis, cluster analysis, phenotypic profiling, plant breeding, climate resilience, Triticum aestivum, proline content, field capacity, semi-arid regions

Researchers at the University of Torino planted twelve different mixtures of herbaceous perennial species across 36 experimental plots at the Bosco Le Risere nursery in Candiolo, Piedmont. Each plot covered four square meters and held 15 plants per square meter, transplanted in autumn 2021 and mulched with volcanic lapillus. From April 2022 onward, the plots received no irrigation and no fertilization for three consecutive years. The only maintenance was periodic manual weeding twice per year and removal of senescent biomass in late winter and mid-summer. This regime deliberately mimicked the constraints facing public green spaces in Mediterranean and temperate cities, where water restrictions and shrinking maintenance budgets are becoming the norm rather than the exception.

The results, published in Frontiers in Horticulture, reveal that what matters most is not how many species a mixture contains but which functional traits those species bring. Mixtures dominated by drought-tolerant graminoids such as Carex flacca and Festuca glauca ‘Elijah Blue’, combined with mat-forming succulents like Sedum reflexum and Sedum spurium ‘John Creech’, and with woolly-foliaged perennials such as Stachys byzantina, rapidly achieved canopy closure above 89 percent and maintained it throughout the trial. These same mixtures kept ornamental quality scores above 81 percent on a 0-to-100 visual scale assessed monthly by a single trained observer, and they suppressed weeds so effectively that the best performer, mixture sG, produced only 160.6 grams of fresh weed biomass per weeding event, accumulating just 963.5 grams over three years.

At the opposite end of the spectrum, mixtures sY and sZ, which lacked persistent canopy-forming species adapted to full sun and summer drought, never established properly. Their mean ground cover hovered around 30 percent, ornamental quality fell below 28 percent, and they accumulated as much as 8,181 grams of weed biomass over the same period. The gap between the best and worst performers was not marginal; it was the difference between a self-sustaining living mulch and an abandoned patch of bare soil. Ground cover across all mixtures rose from 63.4 percent in year one to 80.2 percent in year three, but the rate of improvement depended entirely on whether the planted species could close canopy quickly enough to shade out competitors before weeds gained a foothold.

The mechanism behind this divergence is functional complementarity. Dense graminoids capture resources at soil level, mat-forming succulents occupy horizontal space with evergreen or semi-evergreen foliage, and aromatic stress-tolerant perennials fill vertical gaps. Together these traits create near-ground shading and a living mulch effect that limits light availability at the soil surface and reduces recruitment niches for spontaneous vegetation. The progressive dominance of Stachys byzantina in the best-performing mixture also highlights that interspecific competition shapes long-term stability, meaning designers must account not only for initial complementarity but for how competitive hierarchies shift as communities mature under low-input conditions.

Beyond vegetation performance, the experiment monitored insect biodiversity using two complementary bioindicator groups. Over 2023 and 2024, researchers deployed 20 pitfall traps filled with red vinegar and dish soap along a transect, checking them every 15 days, and counted 6,897 carabid beetle individuals. The most abundant species was Abax contractus, accounting for 34.6 percent of the total catch, followed by Harpalus rufipes at 21.8 percent. Butterfly monitoring used the standardized Pollard transect walk method along a 200-meter route divided into 50-meter sections, surveyed between 10 am and 4 pm under optimal weather conditions, and recorded 2,271 individuals. Pieris napi dominated at 32.8 percent, with Polyommatus icarus and Maniola jurtina also well represented.

Insect abundance followed a pronounced seasonal pattern for both groups. Carabid beetle activity-density rose from 291 individuals in early spring to a peak of 1,396 in late summer before declining to 614 in early autumn. Butterflies followed a similar trajectory, climbing from 71 in early spring to 999 in late summer. The Shannon-Wiener diversity index for carabids increased from 1.87 in 2023 to 2.01 in 2024, suggesting that the progressive establishment of dense perennial vegetation created increasingly favourable habitat structure, shelter, and trophic resources rather than reducing biodiversity over time. For butterflies, the Shannon index was slightly higher in 2023 at 1.68 than in 2024 at 1.50.

Two records of particular conservation significance emerged from the monitoring. The researchers detected Lycaena dispar, the large copper butterfly, and Lucanus cervus, the European stag beetle, both listed as priority species under the EU Habitats Directive. They also recorded the carabid beetle Stenolophus marginatus, a hygrophilous specialist associated with humid, organic-matter-rich substrates, whose regional expansion in Piedmont, Switzerland, and the Aosta Valley has been documented only since the 2010s. Its presence suggests that the experimental perennial mixtures foster moist micro-refugia and organic matter accumulation even within an urban matrix, conditions typically associated with fertilised hay meadows rather than low-input ornamental plantings.

Flowering dynamics added another layer to the picture. Flowering peaked in late spring with an average of 1.9 blooming taxa per assessment and declined sharply from autumn onward, becoming almost absent in winter. Mixture sC, which combined Dianthus barbatus, Gaura lindheimeri ‘Siskiyou Pink’, Hemerocallis ‘Stella de Oro’, Phlox subulata ‘Mac Daniels’, and Potentilla neumanniana, supported the highest flowering diversity with up to 4.7 simultaneously blooming taxa during spring and early summer. Mixture sA extended nectar availability through Lythrum salicaria, Mentha suaveolens, and Saponaria officinalis. However, the number of blooming taxa declined over the three years, from 1.0 in year one to 0.6 in year three, indicating increasing dominance of the most competitive species and a progressive compression of floral resources into a narrower seasonal window.

The authors conclude that combining flowering-rich mixtures like sC and sA, which provide seasonally complementary floral resources for pollinators, with structurally persistent weed-suppressive mixtures like sG, which create favourable microhabitats for ground-dwelling arthropods, represents the most effective strategy for multifunctional urban plantings. Carabid beetles may also contribute to weed seed regulation, adding another ecological service to the list. These findings underscore that trait-based species selection, validated through long-term field evaluation rather than short-term trials, is essential for designing biodiversity-oriented green infrastructure that can withstand the climatic and management constraints facing cities today. Perennial herbaceous mixtures, when composed with functional complementarity in mind, offer a resilient alternative to conventional lawns that reduces water, fertilizer, and labour inputs while simultaneously supporting pollinators, ground beetles, and species of conservation concern.

Subject of Research: Functional composition of perennial herbaceous mixtures drives vegetation stability, weed control and biodiversity in low-maintenance urban green spaces

Article Title: Functional composition of perennial herbaceous mixtures drives vegetation stability, weed control and biodiversity in low-maintenance urban green spaces

Article References: Caser, M., Pomatto, E., Busato, E., Gallizia, S., Devecchi, M., Ferracini, C., & Larcher, F. (2026). Functional composition of perennial herbaceous mixtures drives vegetation stability, weed control and biodiversity in low-maintenance urban green spaces. Frontiers in Horticulture, 5, Article 1923775. https://doi.org/10.3389/fhort.2026.1923775

Image Credits: AI Generated

DOI: 10.3389/fhort.2026.1923775

Keywords: perennial mixtures, urban green spaces, weed suppression, biodiversity, carabid beetles, butterflies, drought tolerance, low-input landscaping, pollinators, functional complementarity, living mulch, Habitats Directive

The research, conducted during the 2022/2023 main cropping season, took place across two contrasting districts in Eastern Amhara: Dawa Cheffa in the South Wollo Zone and Ambasel in the Oromia Special Zone. These locations represent the major mung bean-growing agro-ecologies of the region, sitting at altitudes of 1,400 to 1,680 meters above sea level on vertisol soils. Cheffa receives roughly 850 millimeters of annual rainfall while Jari receives about 1,204.6 millimeters, providing a natural gradient of moisture conditions under which to test varietal performance. The study employed a participatory varietal selection approach, a methodology that deliberately places farmers at the center of the evaluation process rather than treating them as passive recipients of researcher decisions.

Four mung bean varieties entered the trials: three improved types released by Ethiopian agricultural research centers, namely Rasa (also designated N-26), NVL-01, and Boreda, alongside Shewa Robit, a widely grown local variety that served as the farmers’ familiar benchmark. The experimental design followed what researchers call the mother and baby trial approach. Mother trials, managed under strict scientific protocols at research sites, used a randomized complete block design with four replications, planting each variety in five-row plots of three meters with 0.4-meter row spacing and 5-centimeter plant spacing. Baby trials, conducted on farmers’ own fields with each farmer serving as a replication, used larger 25-square-meter plots of five by five meters. This dual structure allowed researchers to capture both statistically rigorous agronomic data and the messier, more nuanced realities of how varieties perform under actual farm conditions.

The combined analysis of variance revealed statistically significant differences among the varieties for every parameter measured, from days to flowering through days to maturity, plant height, pods per plant, seeds per pod, hundred seed weight, and ultimately grain yield. Rasa emerged as the clear agronomic leader, producing a mean seed yield of 1,731 kilograms per hectare across both locations. Boreda followed closely at 1,690 kilograms per hectare, a difference that, while numerically apparent, did not reach statistical significance. Both varieties substantially outperformed NVL-01, which yielded 1,225 kilograms per hectare, and the local check Shewa Robit, which produced only 1,020 kilograms per hectare. The yield gap between the best improved variety and the local landrace represents a potential 70 percent increase simply from switching varieties, a margin that could fundamentally alter household economics in the region.

Beyond raw yield, the physiological differences between varieties told an important story. Rasa and Boreda both achieved a hundred seed weight of 5.6 grams, significantly heavier than NVL-01 at 5.3 grams and Shewa Robit at just 3.7 grams. Heavier seeds generally correlate with better market acceptance and higher prices. Rasa also produced the most pods per plant at 15.12, followed by Boreda at 14.80, NVL-01 at 11.95, and Shewa Robit at 10.15. Seeds per pod followed the same hierarchy, with Rasa producing 11.70 seeds per pod compared to Shewa Robit’s 9.28. Plant height, which matters to farmers because taller plants produce more straw for animal feed, ranged from 55.27 centimeters in Rasa down to 51.32 centimeters in Shewa Robit, a statistically significant difference that farmers noted during their field evaluations.

Disease pressure emerged as one of the most decisive factors separating the varieties. Cercospora leaf spot and anthracnose, two of the most destructive mung bean pathogens in the region, ravaged the local Shewa Robit variety and, to a lesser extent, NVL-01. Shewa Robit recorded an anthracnose score of 3.5 on a five-point severity scale, the worst of any variety tested, while Rasa scored just 1.875, indicating substantially better tolerance. For farmers who have watched entire seasons decimated by disease, this difference alone justified switching. The study’s authors note that these diseases, along with yellow mosaic virus and dry root rot, continue to severely limit mung bean productivity across the region, making genetic resistance a top priority in any breeding or selection program.

The participatory component of the research revealed fascinating insights into what farmers actually value. A total of 39 farmers participated in the selection process across the two districts, including 19 male-headed and 4 female-headed households in Dawa Cheffa and 16 male-headed households in Ambasel, where no female participants were available. Through extensive group discussions, farmers established their own selection criteria, which included pod number, seed yield, earliness, seed size, seed color, marketability, disease resistance, drought tolerance, uniform maturity, and straw biomass. Using pairwise matrix ranking, farmers then prioritized these criteria. Disease resistance emerged as the single most important trait at both locations, followed by pod number as the second priority. Seed yield and seed color tied for third place, while straw biomass received the lowest ranking, a finding that surprised some researchers who had assumed fodder value would weigh more heavily in farmer decisions.

Direct matrix ranking then allowed farmers to score each variety against each criterion on a scale from one, meaning very good, to five, meaning extremely poor. The results were remarkably consistent across both districts. At Dawa Cheffa, Rasa received the lowest cumulative score of 79, indicating the highest preference, followed by Boreda at 81, Shewa Robit at 105, and NVL-01 at 125. At Ambasel, the pattern repeated almost identically: Rasa scored 65, Boreda 73, NVL-01 114, and Shewa Robit 128. The convergence of scientific yield data and farmer preference rankings on the same two varieties, Rasa and Boreda, represents a powerful validation of both the varieties themselves and the participatory methodology. When farmers and breeders agree, adoption barriers crumble.

Following the selection phase, the research team moved into a pre-scaling-up phase for Rasa, the variety that topped both the yield tables and the farmer preference rankings. Selected farmers received seeds of the chosen variety along with training on recommended seed production and management packages delivered by Sirinka Agricultural Research Center researchers. Development agents and woreda agricultural office experts also participated in the training sessions. A multidisciplinary team of researchers, policymakers, and agricultural experts conducted regular field inspections throughout the growing season, monitoring progress, troubleshooting problems, and advising on everything from land selection through harvest. This phased, hands-on approach to technology dissemination reflects a growing recognition within Ethiopian agricultural research that the gap between variety release and farmer adoption has historically been one of the weakest links in the innovation chain.

The implications of this study extend well beyond the borders of Eastern Amhara. Ethiopia currently produces mung bean on approximately 48,022 hectares nationally, yielding about 51,569 tons, with the Amhara region alone accounting for 68 percent of the national area and 72 percent of national productivity. Yet average yields of 1.073 tons per hectare nationally and 1.133 tons per hectare regionally remain far below the two tons per hectare achievable under experimental conditions. The study demonstrates that closing this gap requires not just better varieties but better processes for getting those varieties into farmers’ hands. By involving farmers directly in evaluation, the researchers accelerated adoption timelines and ensured that the traits farmers actually care about, particularly disease resistance and pod number, were not overlooked in favor of traits that breeders might prioritize in isolation. As climate variability intensifies across the Horn of Africa, the lessons from these Ethiopian mung bean fields offer a template for how participatory approaches can build more resilient and productive agricultural systems from the ground up.

Subject of Research: Participatory varietal selection of mung bean varieties in Eastern Amhara, Ethiopia

Article Title: Participatory selection of mung bean ( Vigna radiata L.) varieties in Eastern Amhara region, Ethiopia

Article References: Tefera, M., Kebede, G., & Haile, A. (2025). Participatory selection of mung bean (Vigna radiata L.) varieties in Eastern Amhara region, Ethiopia. Innovations in Agriculture, 8, 1-8. https://doi.org/10.3897/ia.2025.163481

Image Credits: AI Generated

DOI: 10.3897/ia.2025.163481

Keywords: mung bean, participatory varietal selection, Ethiopia, Amhara region, disease resistance, crop yield, smallholder farmers, Rasa variety, Boreda variety, drought tolerance, pulse crops, agricultural research

The editorial accompanies a special Research Topic in the journal collecting four studies that probe bacterial contributions to soil health at scales ranging from single genomes to entire farming landscapes. Together, they make a case that has been building in the microbiome literature for years: function, not diversity alone, is what determines whether a soil supports vigorous crops or merely hosts a long list of microbial names. The authors contend that many microbiome studies remain descriptive, focusing on cataloguing microbial diversity without elucidating the underlying mechanisms. Closing that gap, they argue, is essential if microbiome science is ever to deliver reliable tools for agriculture.

The first study in the collection offers a striking example of how much a single bacterial strain can accomplish. Researchers led by Zhang and colleagues isolated Stenotrophomonas rhizophila T3E from tomato rhizosphere soil, the narrow zone of soil directly influenced by plant roots. When they inoculated tomato plants with T3E, the effects rippled through both plant and soil. Root development improved markedly, the bacterium modulated plant hormones including indole-3-acetic acid and abscisic acid, antioxidant systems were strengthened, and multiple genes involved in root development were upregulated.

What makes this work technically notable is the breadth of evidence the researchers assembled. Beyond the plant responses, they documented changes in the soil environment itself: total nitrogen, total and available phosphorus, and available potassium all rose following inoculation. The activities of four soil enzymes, phosphatase, urease, catalase, and sucrase, were also significantly enhanced. These enzymes are workhorses of nutrient cycling and organic matter decomposition, so their elevation signals a genuine shift in soil biochemistry rather than a transient boost to one plant. By combining whole-genome sequencing with physiological and biochemical measurements, the team provided direct experimental backing for proposed mechanisms, moving beyond correlation into causation.

Phosphorus occupies a central place in this story because it remains one of the most persistent limits on global crop productivity. Most soil phosphorus exists in chemical forms that plants cannot access, and the standard remedy, overapplying phosphate fertilizers, carries steep environmental costs, from waterway eutrophication to the depletion of finite rock phosphate reserves. Shayanthan and colleagues attacked this problem by characterizing phosphate-solubilizing Paraburkholderia strains from agricultural soils and demonstrating their ability to enhance early soybean growth. These bacteria can unlock otherwise inaccessible phosphorus, potentially reducing dependence on synthetic fertilizers.

The genomic surprises in that study underline how little we still know about microbial metabolism in farm soils. When the researchers integrated plant growth-promotion assays with complete genome sequencing, they discovered a full Calvin-Benson-Bassham pathway, a carbon fixation route rarely associated with this bacterial taxon. Even more instructive was the substantial strain-level genomic and metabolic variation they uncovered within the genus. The lesson, the editorial authors stress, is that taxonomy alone rarely predicts function. Effective bioinoculants, they argue, should be locally adapted, identified at the strain level, and tested under realistic soil conditions rather than in generic laboratory media.

Scaling up from single strains, the collection includes a long-term field experiment by Cerecetto and colleagues in the Uruguayan Pampa that examined how farming system design shapes microbial communities. Spanning a gradient of land use intensities from continuous cropping to natural grassland, the study found that extended pasture phases sustain soil organic carbon, nitrogen pools, and microbial functional indicators. Intriguingly, microbial community composition, rather than alpha-diversity, the simple count of species present, emerged as the strong predictor of soil functionality and crop performance. Pasture-based systems preferentially enriched genera such as Streptomyces, Pseudomonas, Bacillus, and Microbacterium, many of which carry multiple plant-beneficial traits.

This work highlights a concept gaining traction in soil ecology: managed soil legacy, the long-lasting influence of past management on microbial community structure and function. Remarkably, the pasture-derived microbial legacy persisted years after the pasture was removed and continued to support subsequent crop performance. For mixed crop-livestock systems around the world, that finding suggests a practical strategy, rotating crops through pasture phases not just for the immediate nutrients they provide, but for the beneficial microbial communities they install and the resilience they leave behind.

The fourth study takes microbial engineering to its most ambitious level. Rigerte and colleagues constructed a drought-tolerant synthetic microbial community, dubbed DT-SynCom, to improve barley performance under water stress. Sixteen bacterial strains were isolated from barley rhizospheres exposed to simulated future climate conditions and selected on the basis of drought tolerance, rhizosphere enrichment, and plant growth-promoting characteristics. The resulting consortium, composed of Actinobacteria, Proteobacteria, and Firmicutes, reduced leaf wilting and improved barley performance under drought. Genome-resolved analyses combined with trait screening revealed complementary functional capacities distributed across the strains, including ACC deaminase activity, auxin biosynthesis, phosphate solubilisation, siderophore production, and osmoprotectant pathways. The design relied on ecological filters, selecting strains for environmental relevance and functional traits rather than arbitrary criteria, an approach the editorial authors single out as a model for bridging controlled experiments with field-relevant microbial selection.

Reading the four studies together, a consistent pattern emerges: bacterial contributions to soil health are stubbornly context dependent. Soil type, climate, cropping system, and management history all determine which microbial functions are expressed or suppressed. A strain that supercharges tomatoes in one field may do little in another, and a community assembled for Uruguayan pastures will not transfer cleanly to German barley fields. This context dependence argues strongly for locally sourced microbial strains over generalist inoculant mixes, and it explains why the editorial authors insist that genomic and phenotypic evidence must be integrated. Genome-resolved analyses reveal metabolic potential, what a bacterium could theoretically do, while realized function can only be determined through trait assays, plant responses, and soil measurements.

The gap between laboratory promise and field reliability remains the field’s central challenge, and the editorial does not shy away from it. Synthetic communities and single-strain inoculants alike must establish themselves and function within resident soil microbiomes, and benefits observed under controlled conditions often fail to translate to complex field environments. Regulatory frameworks for microbial biofertilizers continue to lag behind scientific advances in many jurisdictions, and questions of equitable access remain inadequately addressed. The authors point out that small-scale farmers, who stand to benefit most from reduced reliance on synthetic inputs, still face significant barriers to adoption and deserve greater attention from researchers and policymakers alike.

Looking ahead, the editorial lays out a research agenda. Long-term field trials and multi-environment experiments are essential to determine the persistence, robustness, and scalability of microbiome-mediated benefits under realistic conditions. Targeted exclusion and reassembly experiments within synthetic communities will help identify keystone taxa, quantify functional redundancy, and map the interaction networks that underpin system stability. And pasture-based rotations that sustain organic matter inputs and maintain microbial habitat continuity may help plants recruit beneficial microbiota and enhance overall system resilience.

The big picture emerging from this collection is that soil health is not a product of isolated microbes or short-term interventions, but of interacting traits, communities, and management legacies accumulated over years. A farmer’s decision to plant pasture today can echo through the microbial community for seasons afterward, quietly boosting the crops that follow. By championing function-driven, genome-informed, and ecologically contextualised research, the studies gathered here point toward a future in which the soil microbiome is treated not as an afterthought of agronomy, but as infrastructure, living infrastructure that, if managed wisely, could anchor sustainable and climate-resilient agriculture for decades to come.

Subject of Research: Bacterial contributions to soil health and plant microbiomes in sustainable agriculture

Article Title: Editorial: Bacteria’s role in soil health and microbiomes

Article References: Raghavendra, A., & Bickel, S. (2026). Editorial: Bacteria’s role in soil health and microbiomes. Frontiers in Bacteriology, 5, Article 1921131. https://doi.org/10.3389/fbrio.2026.1921131

Image Credits: AI Generated

DOI: 10.3389/fbrio.2026.1921131

Keywords: soil microbiome, bacteria, sustainable agriculture, synthetic microbial communities, phosphate solubilisation, soil legacy, plant growth-promoting rhizobacteria, drought tolerance, Stenotrophomonas rhizophila, Paraburkholderia, soil enzymes, crop resilience

Sorghum is the fifth most important cereal crop globally, after maize, rice, wheat, and barley, and it occupies a special position in sub-Saharan Africa as a food-security anchor in semi-arid environments. Thanks to its genetic makeup, biochemical profile, and photosynthetic efficiency, sorghum tolerates drought better than most staples, which is why researchers describe it as a climate-smart crop. In Ethiopia it is the second most important staple after maize, cultivated on approximately 1.8 million hectares. In the Amhara region, sorghum covers about 14 percent of the four million hectares planted with field crops, some 650,000 hectares contributing roughly 16 percent of regional cereal production.

Yet productivity has lagged far behind potential. National average yields were only 1.3 tons per hectare in the late 1990s, and although they have since risen to around 2.3 tons per hectare, eastern Amhara’s sorghum fields remain dominated by local landraces grown with few recommended agronomic practices. The region’s lowlands, including the Yeju-Kewet sorghum cluster stretching from the Kobo-Alamata plain to Kewet, are chronically food insecure; 77 percent of the Amhara region’s safety-net users come from these eastern areas. Recurrent drought, low soil fertility, Striga infestation, pests, and erratic rainfall marked by late onset and early termination all conspire against farmers, and late-maturing local varieties that need seven to eight months in the field are becoming untenable as the climate shifts.

Recognizing these constraints, regional and federal research institutes had already released improved early-maturing varieties, and on-farm demonstrations suggested yield advantages of 70 to 90 percent over farmers’ practices. But adoption stalled. Improved seed was scarce, extension linkages were weak, awareness was limited, and gender-related barriers restricted access to new technologies. The new study, published in Innovations in Agriculture, set out to break that logjam by pre-scaling Girana-1 and Melkam with their full agronomic packages, aiming to create demand, stimulate seed multiplication, and strengthen the web of stakeholders who must cooperate for technology to spread.

The intervention covered Kobo, Habru, Kalu, and Dawa Chefa districts in the North Wollo, South Wollo, and Oromia Special Zones, each characterized by lowland agro-ecologies where the rains rarely last more than three months from late June to early September. Using a multi-stage purposive selection, the researchers enrolled 273 farmers, including 50 female-headed households, who cultivated a total of 80 hectares of adjacent, clustered farms across seven kebeles. Clustering was a deliberate design choice: contiguous plots made monitoring easier, improved weed and pest management, reduced damage from wild animals, and helped build market linkages within the production areas.

The technology package was agronomically precise. Farmers planted at a seed rate of 12 kilograms per hectare, applied 100 kilograms per hectare of NPS fertilizer and 50 kilograms per hectare of urea, with 39 kilograms of that urea side-dressed at the knee-height stage, spaced rows 75 centimeters apart and plants 15 centimeters apart, thinned 20 days after planting, and constructed tie-ridges to conserve moisture. Dissemination followed a structured sequence: a launch workshop and memorandum of understanding among stakeholders, two-day training combining theory and practice for farmers and extension agents, printed materials in Amharic and English, field days, and joint monitoring at key crop growth stages. Field days alone drew 338 participants, 78 of them women, who evaluated earliness, seed color and size, uniformity, threshability, and suitability for intercropping.

The yield results provide the strongest evidence yet for scaling. Girana-1 delivered mean grain yields of 4.57, 3.50, and 3.65 tons per hectare at Raya Kobo, Habru, and Dawa Chefa respectively, corresponding to advantages of 43.45, 27.27, and 73.8 percent over local varieties. Melkam performed even more dramatically, averaging 3.98 tons per hectare at Kobo, 4.80 at Habru, 4.15 at Kalu, and 3.80 at Dawa Chefa, with yield advantages of 59.2, 74.54, 88.63, and 73.37 percent. The exceptional result in Kalu suggests the variety is particularly well matched to that district’s soil moisture and management conditions, consistent with earlier findings identifying Melkam as a high-yielding, stable, widely adaptable option for drylands.

One trade-off emerged: Melkam’s shorter stalks reduce total biomass compared with local varieties, although farmers found its stalks more palatable as livestock feed. Because sorghum grain feeds people while stalks feed animals and fuel household fires, this dual-purpose dimension matters greatly to farmer preference. Farmers reported that Melkam’s shorter height actually improves tolerance to wind damage, and that both varieties thresh easily and are free from a local health concern known as qinqn, simplifying post-harvest handling. Many participants said they intend to intercrop the new varieties with mung bean, haricot bean, and forage species to offset any feed shortfall.

Farmers’ preferences, measured with a Relative Importance Index, revealed complementary strengths. Melkam topped nearly every trait evaluated, with a uniform crop stand, early maturity, and intercropping suitability, though its white seed and short stalk make it more vulnerable to bird damage. Girana-1 scored well on grain color and size, stalk palatability, marketability, and livestock feed value. Sensory evaluations of food quality added another layer of nuance: Melkam was preferred for porridge, injera taste, and injera color, while Girana-1 excelled in fermentation-related traits such as local beer quality, injera baking quality, lusciousness, and flour water-holding capacity. The two varieties thus serve complementary roles in Ethiopian kitchens as well as fields.

A total of 1,230 kilograms of seed, 825 kilograms of Girana-1 and 405 kilograms of Melkam, was distributed, with initial seed revolving to reach additional farmers through a farmer-to-farmer exchange mechanism designed to keep seed affordable, high in quality, and locally available. The researchers conclude that a coordinated multi-stakeholder approach, spanning research centers, agricultural offices, cooperatives, unions, seed enterprises, NGOs, and the Bureau of Agriculture, is essential to sustain community-based seed systems and market linkages. They also call for further research into fall armyworm, stalk borer, and emerging pests, along with food-science assessments along the value chain. If the momentum holds, the humble early-maturing sorghum plant may become one of eastern Africa’s most powerful tools against climate-driven hunger.

Subject of Research: Pre-scaling up of improved early-maturing sorghum varieties in moisture-deficient eastern Amhara, Ethiopia

Article Title: Pre-scaling up of early maturing sorghum ( Sorghum bicolor L.) technologies in moisture-deficient areas of eastern Amhara, Ethiopia

Article References: Haile, A., Siyum, N., Bahta, M., & Assefa, M. (2026). Pre-scaling up of early maturing sorghum (Sorghum bicolor L.) technologies in moisture-deficient areas of eastern Amhara, Ethiopia. Innovations in Agriculture, 9, Article e180604. https://doi.org/10.3897/ia.2026.180604

Image Credits: AI Generated

DOI: 10.3897/ia.2026.180604

Keywords: sorghum, Ethiopia, drought tolerance, early maturity, food security, yield advantage, seed systems, agricultural extension, climate-smart agriculture, Girana-1, Melkam, Amhara region

Telomere-to-telomere assemblies represent the current gold standard of genome sequencing. Rather than leaving gaps where repetitive DNA confounds reconstruction, a T2T genome traces each chromosome from one physical end to the other, capturing centromeres, telomeres and other tandemly repeated regions that earlier draft assemblies simply omitted. For licorice, this mattered because the genus had long lacked near-complete genome assemblies, limiting both the study of how bioactive metabolites such as glycyrrhizic acid, liquiritin, licochalcone A and glabridin are synthesized and the investigation of how these plants endure extreme aridity, salinity and heat. The new G. uralensis T2T assembly resolves all eight chromosomes with complete telomeres and fully characterized centromeres, providing a reference against which other licorice genomes and populations can be aligned with confidence.

A particularly striking technical achievement of the assembly is its characterization of centromeric DNA. The researchers identified two centromeric tandem repeat monomers, designated Cen60 and Cen307, with the latter appearing to be specific to chromosome 4 of G. uralensis. To confirm that these repeat sequences genuinely mark the centromeres rather than being assembly artifacts, the team performed oligo-fluorescence in situ hybridization (FISH) experiments using eight chromosome-specific painting probes together with probes for Cen60 and Cen307. The cytological results matched the sequence-based predictions, anchoring the computational assembly to physical chromosome structure. In parallel with the T2T effort, the consortium produced chromosome-level assemblies for all three pharmacopoeia species, enabling comparative analyses of synteny across the genus and a Circos-plot visualization of structural relationships among the genomes.

With high-quality references in hand, the team turned to natural diversity. They generated re-sequencing data for 188 wild licorice accessions collected across Xinjiang, a region in northwestern China where vast desert and semi-desert habitats harbor major wild licorice populations. From these data, the researchers constructed a large-scale genomic variation map that catalogues millions of single-nucleotide polymorphisms, insertions and deletions across the genus. Population-genomic analyses revealed a clear pattern of geographic and genetic differentiation shaped by the Tianshan Mountains, a massive range that divides Xinjiang into distinct ecological zones. G. uralensis was found mainly in the northern Xinjiang region (XJN), G. inflata dominates the hotter, more arid southern region (XJS), and G. glabra occurs across the whole region, a distribution that hints at different adaptive histories among the three species.

The population dataset allowed the researchers to move beyond simple cataloguing. They delineated core germplasm groups for G. uralensis and G. inflata, providing breeders with a structured picture of the diversity available for future crossing and selection programs. The analyses also detected extensive introgression between species, meaning that the genomes of wild licorice plants carry DNA segments exchanged through interspecies hybridization events. Such gene flow is scientifically significant because it can transfer adaptive alleles across species boundaries, and it is practically important for breeding programs that may seek to combine the chemical richness of one species with the environmental robustness of another.

To connect genome variation to the traits that make licorice valuable, the team performed selective-sweep scans across the genomes. These scans look for regions where genetic diversity has been unusually reduced, a signature that natural or artificial selection has favored certain haplotypes. In the licorice genomes, dozens of genes under selection were identified, many of them annotated with roles in triterpenoid and flavonoid biosynthesis, the two metabolic pathways that generate glycyrrhizic acid, liquiritin and the chalcone-type flavonoid licochalcone A. This observation suggests that the medicinal chemistry of licorice has been shaped by evolutionary pressures on its wild populations, and it gave the researchers a focused set of candidate genes for downstream validation.

The pivotal step was to integrate multiple layers of functional information. The team combined tissue-specific transcriptome data, RNA-sequencing experiments under abiotic stress treatments, correlation analyses between gene expression and climate variables at collection sites, and a genome-wide association study (GWAS) linking genetic variants to metabolite content. Converging evidence from all four approaches pointed to a single gene, 4CL5, as a major determinant of licochalcone A accumulation. This gene encodes a 4-coumarate-CoA ligase, an enzyme family that channels precursors into phenylpropanoid and flavonoid branches of plant metabolism. Licochalcone A is one of the most intensively studied licorice constituents, noted for anti-inflammatory and other pharmacological activities, so identifying a genetic control point for its production carries both basic-science and applied significance.

Molecular experiments then established the regulatory mechanism. Using yeast one-hybrid screening, dual-luciferase reporter assays and electrophoretic mobility shift assays (EMSA), the researchers demonstrated that a transcription factor named GiPHL1 physically binds a specific DNA motif, the P1BS cis-element, located in the promoter of the Gi4CL5 gene in G. inflata. The prefix Gi denotes the G. inflata orthologs. Binding of GiPHL1 to the P1BS element activates transcription of Gi4CL5, thereby enhancing flux into the pathway that produces licochalcone A. The GiPHL1-Gi4CL5 regulatory module, therefore, functions as a coordinated switch that promotes the biosynthesis of a medicinally important flavonoid.

What makes the discovery especially compelling is that this same module appears to serve two purposes at once. In addition to driving licochalcone A accumulation, the pathway activity it controls contributes to improved stress resistance in G. inflata, the species that thrives in the hot, arid habitats of southern Xinjiang. This dual function offers an elegant evolutionary explanation for why a compound of pharmaceutical interest would be maintained at high levels in wild plants: chalcone-type metabolites can participate in plant defense and stress mitigation, so selection for desert survival may have inadvertently enriched the chemical treasury that human medicine values. The finding thus links metabolite biosynthesis and environmental adaptation in a single genetic circuit, a connection that had long been suspected but not genetically resolved in licorice.

The practical implications of the work extend across several fronts. For molecular breeding, the candidate genes and molecular markers emerging from the selective-sweep, GWAS and regulatory analyses provide tools for precision selection, allowing breeders to develop licorice varieties with higher yields of glycyrrhizic acid, licochalcone A and other active compounds while also carrying alleles that confer stronger tolerance to drought and heat. For synthetic biology, the identification of specific biosynthetic and regulatory genes such as Gi4CL5 and GiPHL1 supplies components that could be deployed in engineered microbes or plant systems to produce licorice-derived substances without harvesting wild populations. The T2T and chromosome-scale reference genomes themselves will serve as foundational infrastructure for future genetics in the genus, much as complete reference genomes have transformed research in rice, maize and other crops. As demand for licorice continues in pharmaceuticals, food and industrial manufacturing, the new genomic resources offer a route toward sustainable utilization of a plant whose value has been appreciated for millennia but whose genes are only now coming into focus.

Subject of Research: Telomere-to-telomere genome assembly of medicinal licorice species and the genetics of metabolite biosynthesis and drought adaptation

Article Title: First telomere-to-telomere (T2T) licorice genome uncovers key genes for medicinal metabolite biosynthesis and desert stress adaptation

Article References: First telomere-to-telomere (T2T) licorice genome uncovers key genes for medicinal metabolite biosynthesis and desert stress adaptation. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: licorice, Glycyrrhiza uralensis, telomere-to-telomere genome, T2T assembly, licoachalcone A, genome-wide association study, transcription factor, drought tolerance, flavonoid biosynthesis, molecular breeding, population genomics, Science China Life Sciences