The scale of the problem the study addresses is enormous. Postharvest losses in Nigeria’s tomato sector are often estimated at up to 45 percent of total production, a figure that ripples through the entire value chain. Lost produce means lost income for the smallholders who dominate the sector, higher prices for consumers, and a paradoxical dependence on imported tomato paste in a country that grows millions of tonnes of fresh fruit each year. Kano State, one of the country’s leading tomato-producing regions, sits at the center of this tension: its irrigated fields and well-developed market linkages supply fresh tomatoes to both northern and southern Nigeria, yet much of that fruit never reaches a buyer in saleable condition.

The chief culprit, according to the research led by Tabeel Yerima Isreal of Landmark University and colleagues, is the humble raffia basket. Woven from palm fronds, these containers have rough interiors, rigid walls, and no standardized shape or ventilation design. Tomatoes stacked inside them are exposed to compression damage and bruising as they are transported over rough roads, and the poor airflow accelerates softening and decay. By contrast, reusable plastic crates, rigid molded containers with smooth surfaces and vented sides, are engineered to protect delicate produce and maintain the airflow that keeps fruit firm. Field measurements in the study bore this out: basket users lost approximately 2,307 kilograms from a total harvest of about 9,179 kilograms, a 25 percent loss rate, while crate users lost around 587 kilograms from roughly 16,683 kilograms harvested, or just 3 percent.

What distinguishes the new analysis from earlier work is its statistical rigor. Many previous studies of postharvest technology adoption have relied on simple comparisons or on methods such as propensity score matching, which can only adjust for characteristics that researchers happen to observe. That leaves a fundamental problem unaddressed: farmers who adopt a new technology may be systematically more educated, wealthier, better connected, or more risk-tolerant than those who do not, so part of any apparent benefit may reflect who adopts rather than what the technology does. The Kano study tackles this with an endogenous switching regression model, estimated under a full information maximum likelihood framework, which jointly models the decision to adopt and the loss outcomes under both adoption and non-adoption regimes, correcting for unobserved heterogeneity through inverse Mills ratio corrections.

The technical machinery matters because it changes the size of the answer. The study computed the average treatment effect on the treated and, in a counterfactual step, what would happen if non-adopters were to switch. In logarithmic terms, adoption reduces financial losses by about 1.35 units, equivalent to roughly a 74 percent decrease, for both groups. The consistency of the estimate across adopters and simulated non-adopters suggests the effect is not an artifact of self-selection, and the authors note that simpler group comparisons could actually understate the technology’s true benefit once selection bias and producer heterogeneity are properly handled.

Who adopts, and who does not, turns out to be a story about resources and institutions. Farming experience and years of formal education both increased the probability of adoption, consistent with the idea that experienced farmers have watched enough produce rot to recognize the value of protection, and that education builds the information-processing capacity that human capital theory identifies as central to innovation uptake. Income from tomato production exerted an even stronger pull, a reminder that even a modest investment in crates can be out of reach for producers living hand to mouth. Membership in cooperative societies and engagement in diversified livelihoods also boosted adoption, pointing to the role of social capital and financial resilience in buffering the risks of trying something new.

Two negative findings carry their own policy weight. Female farmers were significantly less likely to adopt crates, a pattern the authors attribute to persistent gender disparities in access to credit, extension services, and productive resources across Nigerian agriculture. And, perhaps counterintuitively, farmers with larger plots were less likely to adopt. The explanation is logistical rather than financial: a grower with extensive fields needs a very large inventory of crates plus the transport and storage space to move and house them, and without supporting infrastructure, scaling crate-based handling across a big operation becomes cumbersome. Similar dynamics have been observed with solar-powered cold storage, where larger harvest volumes overwhelmed the technology’s capacity.

Equally revealing is how adoption actually happens on the ground. The study found that most producers use plastic crates alongside raffia baskets rather than replacing them entirely, a partial adoption pattern that dilutes the technology’s potential. The sampled farmers averaged about 15 years of farming experience, roughly 10 years of schooling, and small plots averaging 1.19 hectares. Only 13 percent had access to formal credit, and 48 percent belonged to cooperatives, figures that sketch the structural constraints within which adoption decisions are made. In a system where capital is scarce and institutional support thin, a hybrid approach, using crates where they are available and baskets where they are not, is a rational compromise rather than a failure of understanding.

The study’s recommendations follow directly from its evidence. Because income and financial capacity were decisive, the authors argue for targeted subsidy programs, credit schemes, and cooperative-based bulk purchasing to bring crate costs down. Cooperatives emerge as a particularly promising delivery channel, since collective procurement lowers individual costs while creating platforms for knowledge sharing. Extension services, the authors suggest, should run demonstration programs that communicate the technical and economic case for crates, especially to less-educated and less-experienced producers, and should recruit experienced adopters as peer educators. Gender-responsive measures, including women-focused savings groups and deliberate inclusion in extension programs, are flagged as essential to closing the adoption gap for female farmers.

The authors are careful to note the limitations of their approach. The cross-sectional design captures a single moment in time and cannot track how adoption behavior evolves, and even a well-specified switching regression cannot fully account for unobservable factors such as individual risk preferences or shifting market conditions. The focus on Kano State also raises questions about generalizability to other regions and cropping systems. Still, the core message is hard to dispute: for every 100 kilograms of tomatoes harvested in Kano’s fields, raffia basket users lose about 25 kilograms before their produce reaches a market, while crate users lose just 3. In a country where tomatoes are both a dietary staple and a livelihood for hundreds of thousands of smallholders, a simple molded plastic box, backed by credit, cooperatives, and good extension, may be one of the cheapest food-security interventions available.

Subject of Research: Impact of reusable plastic crate adoption on postharvest losses among smallholder tomato producers in Kano State, Nigeria

Article Title: Impact of adopting re-usable plastic crates on postharvest losses among small scale tomato producers in Kano State, Nigeria

Article References: Yerima Isreal, T., Bamiro, O. M., & Kehinde, M. O. (2026). Impact of adopting re-usable plastic crates on postharvest losses among small scale tomato producers in Kano State, Nigeria. Discover Agriculture, 4(1), Article 320. https://doi.org/10.1007/s44279-026-00793-z

Image Credits: AI Generated

DOI: 10.1007/s44279-026-00793-z

Keywords: postharvest losses, reusable plastic crates, tomato production, Nigeria, Kano State, smallholder farmers, endogenous switching regression, raffia baskets, food security, agricultural technology adoption, cooperatives, value chain

The data reveal a climate that refuses to sit still. Relative humidity in the study area fluctuated between a low of 42.46 percent in 2006 and a high of 65.09 percent in 2022, a range wide enough to alter evaporation rates, disease pressure, and the water balance of paddy fields. Maximum temperatures ranged from 36.88 degrees Celsius in 2022 to a scorching 42.27 degrees Celsius in 2010, while minimum temperatures displayed an even more dramatic spread, dipping to 5.48 degrees Celsius in 2015 and climbing to 11.96 degrees Celsius in 2017. Such nocturnal temperature swings matter enormously for rice, because cool nights slow crop development while warm nights accelerate respiration and erode the biomass a plant has spent the day building.

Rainfall, the single most consequential variable for rainfed and irrigated agriculture alike, proved the most volatile of all. Annual totals climbed from 454.9 millimeters in 2018 to an extraordinary 3,101.6 millimeters in 2021, before collapsing back to 1,505.9 millimeters in 2022. To put those numbers in perspective, the 2021 figure was nearly seven times the 2018 total, a swing that no farming calendar can comfortably absorb. The authors found that such excessive annual rainfall induced flooding, particularly during critical growth stages of the rice crop, and that these flood events translated directly into reduced yields. For a region where rice is both a staple and a commercial crop, the implications are sobering.

Methodologically, the study leaned on a battery of statistical tools designed to extract reliable signals from noisy environmental data. Descriptive statistics such as means and percentages established the baseline climatology, while Spearman’s rank correlation, tested for significance with Student’s t-test, quantified the strength and direction of associations between each climatic variable and rice yield. To detect whether the underlying climate variables were trending over time rather than merely fluctuating, the researchers applied the Mann-Kendall non-parametric trend test, a workhorse of hydro-climatological research that is robust to outliers and does not assume normally distributed data. Sen’s Slope estimator complemented the Mann-Kendall test by providing a robust measure of the magnitude of any trend, expressed as the rate of change per year.

The correlation results upended some intuitive expectations. Maximum temperature showed a positive correlation with rice yield, with a Spearman coefficient of 0.311, and minimum temperature was similarly positive at 0.301. Rainfall, by contrast, was negatively correlated with yield at -0.455, and relative humidity was also negative at -0.255. In other words, in this irrigated setting, hotter years were associated with better harvests while wetter, more humid years were associated with worse ones. The most plausible explanation lies in the fact that Kadawa’s rice is grown under the Kano River Irrigation Project, where water supply does not depend primarily on rainfall. In such systems, abundant sunshine and warmth can boost photosynthesis and crop growth, whereas torrential rainfall overwhelms drainage infrastructure and floods fields at sensitive stages such as flowering and grain filling.

This finding carries a broader lesson for climate impact research: the direction of climate-yield relationships is not universal but depends on the farming system in question. In rainfed rice systems across West Africa, rainfall and yield typically move together, and drought is the dominant threat. Kadawa’s irrigated regime inverts that logic. The negative rainfall-yield correlation of -0.455 is the strongest association in the dataset, suggesting that water excess, not water scarcity, is the principal climatic hazard facing farmers there. It is a reminder that adaptation strategies must be tailored to local hydrological realities rather than copied wholesale from other regions, and that irrigation schemes themselves can create new vulnerabilities when drainage lags behind water delivery.

The marked temporal instability documented in the study echoes a wider body of evidence on climate and agriculture. Global analyses have estimated that climate variation explains roughly a third of worldwide crop yield variability, and West Africa has repeatedly been flagged as a hotspot where rainfall variability and hydroclimatic extremes intersect with food insecurity. Within Nigeria specifically, recent studies have documented warming trends in major cities using the same non-parametric methods employed at Kadawa, and modeling work with the APSIM crop simulation platform has projected climate change effects on rice production across the wider Kano River Irrigation Scheme. The Kadawa study grounds these larger-scale findings in a concrete, thirty-year local record, showing that the variability long predicted for the Sahel is already inscribed in the region’s yield statistics.

The physiological mechanisms linking the observed climate extremes to rice performance are well understood from plant science. Rice is particularly sensitive to temperature during its reproductive phase: daytime temperatures above roughly 35 degrees Celsius can cause spikelet sterility by disrupting anther dehiscence and pollen viability, while high night temperatures increase respiration losses and shorten the grain-filling period. Cold minima, such as the 5.48 degrees Celsius recorded in 2015, can delay seedling establishment and slow early vegetative growth. Flooding, meanwhile, deprives roots and soil of oxygen, promotes toxic reduced compounds, and can fully submerge plants, with complete submergence for more than a few days often proving fatal to intolerant varieties. Humidity shapes the microclimate of the canopy and influences the incidence of fungal diseases such as sheath blight, which thrives under warm, moist conditions.

Against this backdrop, the authors argue that rice cultivation in Kadawa is growing steadily more vulnerable to climatic variability, and they outline a portfolio of adaptive responses. Chief among these are climate-resilient rice varieties, including submergence-tolerant cultivars. Breeding programs have made notable progress here: the SUB1A quantitative trait locus, originally identified in the Indian landrace FR13A, confers tolerance of complete submergence and has been introgressed into popular varieties across South and Southeast Asia, with ongoing research extending these gains and elucidating the underlying metabolic and physiological mechanisms. Deploying such genetics in West African irrigation schemes could buffer harvests against the flood years that the Kadawa record shows are increasingly disruptive.

Equally important, the study emphasizes, are engineering and water-management measures. Improved drainage infrastructure would allow excess rainfall to be evacuated from fields before it reaches damaging depths, directly addressing the negative rainfall-yield relationship at the heart of the findings. Enhanced water-management practices, from regulated irrigation scheduling to field-level water control, would help farmers exploit Kadawa’s warmth and sunshine while shielding the crop from moisture extremes. The authors frame these interventions within the broader agenda of climate-smart agriculture, which seeks to sustain high and stable yields under changing climatic conditions rather than simply maximizing output in good years. As the 2021 to 2022 rainfall collapse demonstrates, the cost of inaction is not hypothetical: a farming system calibrated to one year’s climate can be blindsided the next. With Nigeria among West Africa’s largest rice producers and demand for the grain still rising, the thirty-year Kadawa record offers both a warning and a practical roadmap for keeping harvests stable on a warming, whipsawing climate frontier.

Subject of Research: Long-term climate variability and its effects on rice yield in Kadawa, Kano State, Nigeria

Article Title: Assessing long‑term climate variability and its effects on rice yield in the Kadawa Area, Kano State, Nigeria

Article References: Babatunde, O. R., & Salami, A. A. (2026). Assessing long‑term climate variability and its effects on rice yield in the Kadawa Area, Kano State, Nigeria. Theoretical and Applied Climatology, 157(10), Article 643. https://doi.org/10.1007/s00704-026-06578-0

Image Credits: AI Generated

DOI: 10.1007/s00704-026-06578-0

Keywords: climate variability, rice yield, Nigeria, Kano State, Kadawa, rainfall, temperature, flooding, irrigation, Mann-Kendall trend test, climate-smart agriculture, submergence tolerance