Scientists at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), along with partner institutes, have identified a key gene linked to resistance against Sterility Mosaic Disease (SMD), a devastating condition that can reduce pigeonpea yields by up to 90%. The gene, named Ccsmd04, was discovered in ‘Asha’ (ICPL 87119), a widely cultivated pigeonpea variety developed by ICRISAT that is known for its natural resistance to the disease.
The discovery, made in collaboration with the Indian Institute of Pulses Research (Uttar Pradesh), Dr Rajendra Prasad Central Agricultural University (Bihar) and Indian Agricultural Research Institute (Assam), uses cutting-edge genomics, phenomics and computational analysis to give farmers a powerful new weapon against SMD.
“This is a landmark discovery, considering the severity of SMD in the region. The genetic variants, genes and markers identified have immense potential for breeding more resistant varieties,” said Dr Himanshu Pathak, Director General, ICRISAT.
Researchers found that Ccsmd04 produces a dormancy/auxin-associated protein critical to plant immunity. In susceptible pigeonpea lines, the team identified four frameshift mutations that disrupt the protein’s function. These insights have led to the development of four functional genetic markers, enabling breeders to detect SMD resistance in early crop stages and speed up the release of improved varieties.
ICRISAT has been battling SMD since 1975, but controlling the disease in the field has been a challenge due to the variability of both the virus and its mite vector. “Our genomics and pre-breeding programme focuses on integrating such genetic insights into breeding pipelines. Disease resistance is a top priority because of its direct impact on farmers’ livelihoods,” said Dr Stanford Blade, Deputy Director General, Research and Innovation, ICRISAT.
Lead scientist Dr Manish K. Pandey said the findings also open up possibilities for gene editing to boost resistance further. The team now plans to identify more resistance genes, including those from wild pigeonpea relatives, to ensure stable field-level protection.
With strong partnerships, global support from CGIAR and Gates Foundation, and advanced genomic tools, scientists say this discovery could contribute significantly to India’s quest for self-sufficiency in pulses, offering farmers a sustainable defense against one of pigeonpea’s deadliest threats.
