Researchers at North Carolina State University have unveiled a groundbreaking method that enables the encapsulation of beneficial bacteria, paving the way for innovative agricultural applications. This technique has the potential to enhance plant growth while simultaneously providing protection against pests and diseases. With this new approach, farmers may harness the power of these microbes in tandem with existing agrochemicals, offering a sustainable solution to improve crop yields.
The team, led by Ph.D. student John Cheadle, emphasized the fragility of many plant growth-promoting bacteria (PGPBs), which often complicates their integration into stable agricultural products. These bacteria play a vital role in supporting plant health by facilitating nutrient uptake and shielding plants from harmful pests and pathogens. “By stabilizing these beneficial microorganisms, we have opened doors to creating customized probiotics specifically designed for plants,” Cheadle expressed.
Traditionally, incorporating PGPBs into formulations with agrochemicals posed a significant challenge, as the latter often proved lethal to the bacteria. Co-corresponding author Saad Khan outlined this longstanding issue, noting that the simultaneous application of these two elements has been a significant hurdle in agricultural practice. The innovative emulsion developed through this research serves as a solution, allowing for the healthy coexistence of beneficial bacteria and agrochemicals.
Understanding the importance of a balanced plant microbiome, researcher Tahira Pirzada highlighted the implications of their findings. A robust microbial community within the plant system can enhance nutrient utilization and bolster resistance against pathogens, potentially reducing the need for chemical fertilizers and pesticides. This could lead to more sustainable farming practices that maintain productivity while minimizing environmental impact.
Central to this breakthrough is a specially crafted emulsion, composed of a limited number of ingredients designed to work in synergy. The first component includes a saline solution infused with PGPBs, specifically the bacteria Pseudomonas simiae and Azospirillum brasilense. While P. simiae acts as a biopesticide through its ability to promote pathogen resistance, A. brasilense functions as a biofertilizer, effectively fixing nitrogen in the soil.
The second element of the emulsion consists of a biodegradable oil combined with a cellulose-derived biodegradable polymer. This polymer not only supports the active ingredients from agrochemicals but also avoids the use of harmful organic solvents typically found in pesticide formulations. This form of delivery offers an environmentally friendly alternative for farmers looking to incorporate both biological and chemical agents into their agricultural practices.
When these two components are mixed, an emulsion is created that resembles a salad dressing, with oil droplets uniformly distributed throughout the saline solution. This unique formulation allows for the application of PGPBs alongside agrochemicals, resulting in a versatile product that can be used effectively in various farming scenarios. The investigation into the efficacy of this delivery system involved two pivotal experiments.
The researchers first assessed the survival rates of PGPBs within the emulsion compared to a saline solution devoid of emulsion. They stored samples of both formulations at room temperature over four weeks. Results revealed that the population of P. simiae in the emulsion was remarkably 200% higher than that in the saline solution. Even more impressive, the population of A. brasilense saw a staggering increase of 500%. These findings suggest a significant enhancement in the survivability of these bacteria when delivered through the new emulsion method.
In a second experiment, the researchers tested the efficacy of a pesticide, fluopyram, when incorporated into the emulsion. They introduced nematodes, specifically C. elegans, which act as a proxy for agricultural pests into both the emulsion and saline solution. Unsurprisingly, the saline-distributed fluopyram produced immediate results, with all pests eradicated within an hour. However, the emulsion exhibited a more gradual death rate, eliminating 95% of the nematodes over a span of 72 hours. This slower action may allow farmers to adopt a more strategic approach to pest control, extending the duration of pest protection.
Ultimately, the research team concluded that their technique facilitates the incorporation of multiple active ingredients into a unified delivery system while ensuring the survival and reproductive success of vital PGPBs. As co-lead author Mariam Sohail noted, this advancement represents a significant leap forward in the combined application of biological agents and chemical treatments in agriculture.
Looking ahead, the team plans to conduct greenhouse experiments and eventually microplot studies to further evaluate the performance of various PGPBs and complementary active ingredients across different plant species. Their work has the potential not only to bolster agricultural productivity but also to promote practices that align more closely with sustainable farming objectives.
In collaboration with various stakeholders, this research contributes to the growing body of knowledge on integrating biological solutions within conventional agricultural frameworks. Such efforts underscore the importance of innovative technologies in addressing global agricultural challenges, particularly in the face of increasing concerns over food security and environmental sustainability.
By leveraging advancements in biochemistry and agricultural science, this research may usher in new methods of farming that are increasingly resilient to climate change without compromising crop yields or environmental health. As this research continues to develop, it holds promise for transforming the future of agriculture, making it more effective, sustainable, and beneficial for both farmers and consumers alike.
Subject of Research: Plant Growth-Promoting Bacteria and Agrochemical Delivery Systems
Article Title: Pickering Emulsion for Enhanced Viability of Plant Growth Promoting Bacteria and Combined Delivery of Agrochemicals and Biologics
News Publication Date: 5-Feb-2025
Web References: DOI link
References: Published in Advanced Functional Materials
Image Credits: Not specified
Keywords
Agricultural innovation, beneficial bacteria, PGPB, emulsion technology, sustainability, crop protection, nitrogen fixation, biodegradable polymers, eco-friendly pesticides, agricultural microbiome.
