Yurgel, Svetlana

Svetlana Yurgel

Research Geneticist

Introduction

My research focuses on the improvement of sustainable pulse crop production through enhancement of plant-associated microbial communities (microbiomes). Plant-associated microbiomes play an essential role in crop health and production by improving nutrient uptake, stimulating growth and resistance to environmental stresses, such as drought, heat and pathogenic infections. Additionally, grain legumes are capable to establish symbiotic association with soil rhizobia and convert atmospheric nitrogen (N) to ammonia, which is used as a N source for plant growth and production. Symbiotic N fixation is an important part of sustainable agriculture, which could reduce application of synthetic N fertilizers. Furthermore, rhizobium-legume symbiosis could improve crop protein quality, which is an essential aspect in the development of legume-based foods with enhanced nutritional quality.

 

Breeding legumes for improved yield and seed quality, coupled with extensive use of N fertilization may disrupt the ability of modern cultivars to establish symbiotic associations with native soil rhizobia. Little is known about symbiotic properties and the ability of these new cultivars to establish associations with rhizobia and other bacteria native to Pacific Northwest soils. An emerging area of research interest is to develop effective legume inoculants, incorporating rhizobia and other native fungal and bacterial isolates, which promote crop production and symbiotic N fixation. To address these issues, we are collaborating with ARS scientists from other research units, several universities including University of Idaho and Washington State University, legume crop producers and association across the U.S. Pacific Northwest (PNW), and research institutions outside of the U.S. including Agriculture and Ag-Food Canada (AAFC), Dalhousie University and Memorial University (Canada).

Research at a Glance

Edible legumes such as peas and lentils are nutrient-dense and promote health, income for growers, and enhance yields by fixing soil N that augments productivity of non-leguminous crops in crop rotations. In 2023, the value of pea and lentils production in Washington State (WA) exceeded $79 million. Taking into consideration that the inoculums currently used in WA were developed without discrimination between pea and lentil, there is a strong possibility that these inoculums are not equally efficient on both crops. The goal of our research is to provide specific recommendations for the use of commercial inoculums, as well as create a scientific foundation for developing efficient rhizobial inoculums tailored for pea and lentil production in the PNW.

 

The successful incorporation of legumes in sustainable crop production is based on the ability of the plants to establish N-fixing symbiosis with rhizobia adapted to native soils. We evaluated microbiomes associated with winter pea production system and assessed nodulation potential of native rhizobia across multiple location in PNW. We identified a few locations with native microbiomes capable of establishing robust symbiotic association with winter pea that promote plant growth and health. We isolated and characterized rhizobia and other bacteria and fungi from legume roots and symbiotic organs, nodules, and are conducting tests to identify microorganisms with improved plant growth promotion and N fixation.

 

The results of this project will directly impact growers and consumers by providing advanced management approaches and tools to improve biological N input into agricultural systems, protect legume crops from abiotic and biotic stresses, and support soil health and sustainability. Moreover, this research will improve fundamental understanding of the role and plant growth promotion potential of the microbiome native to dryland PNW soils. The research provides direction for adjusting soil microbiomes and improving legume inoculants to promote more sustainable and economically viable crop production systems that provide significant benefits to the American public.