Research Projects

Soybean (Glycine max L. Merril; 2n=40) is an important crop grown for edible oil (20%), protein (40%) and used for various applications. In India soybean is the number one oilseed crop with a cultivated area of 12.10 mha and production of 12.61 mt with a productivity of 1042 kg/ha (FAOSTAT, 2022). Major soybean growing states are Madhya Pradesh, Maharashtra, Rajasthan, Chhattisgarh, Andhra Pradesh, and Karnataka contributing. In recent years, there has been expansion of soybean growing area in the Southern zone. However, its full yield potential is far from being exploited due to the incidence of biotic and abiotic stresses. The crop suffers from many fungal diseases and among them foliar diseases affect crop yield severely. Soybean rust, caused by the fungus Phakopsora pachyrhizi (Sydow. & Sydow.) is the most devastating foliar disease, which can defoliate the standing crop rapidly and cause yield losses up to 80% under favorable conditions (Stewart et al., 2005). In India, rust occurs in severe form in the major soybean growing regions of Karnataka, Maharashtra, Manipur, Nagaland and Meghalaya causing yield losses upto 80% (Devaraj et al. 2016). Currently, rust is managed by spraying of fungicides, but depending solely on chemical fungicides rises input cost and environmental impact. Furthermore, frequent exposure to fungicides can select for mutations that decrease the sensitivity of P. pachyrhizi populations to fungicides (Godoy, 2012). Breeding soybean cultivars with rust resistance is the most cost-efficient method of sustainable disease management strategies. Resistance to rust has been reported in soybean and race-specific resistance to rust is controlled by resistant genes (Rpp) from seven reported loci (Chander et al. 2019). Knowledge on pathotype variation in and among P. pachyrhizi populations is critical in resistance breeding for deploying appropriate resistance genes or pyramiding of genes based on location specific pathotype. Currently, resistance breeding is hampered by insufficient knowledge of physiological races of P. pachyrhizi in the major rust affected areas of India, which deserves urgent monitoring. Advances in next generation sequencing technologies has enabled development of sequencing-based markers such as SNPs and their application for molecular breeding in soybean. This collaborative proposal between the ICAR-Indian Agricultural Research Institute, New Delhi; and University of Agricultural Sciences, Dharwad, aims at (i) Systematic evaluation of soybean accessions to identify rust resistant lines; (ii) Understanding the race pattern and prevalent P. pachyrhizi pathotypes causing soybean rust in India (iii) Identification of genomic regions associated with resistance to soybean rust. The information generated in this project would be valuable for researchers to develop appropriate resistance breeding strategies and cultivars with long term durable resistance to soybean rust and thus enhance soybean productivity.