| Summary: | Recently, soil borne diseases are posing a greater threat to groundnut production. Stem rot of groundnut is a soil-borne disease caused by the necrotrophic pathogen, Sclerotium rolfsii. Yield losses from major groundnut growing countries of 20–80% have been reported depending on disease intensity. Chemical and cultural practices are used to manage this disease, the soil borne nature of the pathogen and wide host range make it difficult to manage this disease by chemical and cultural methods alone. Additionally, host plant resistance is the most preferred option as it is cost-effective and an environmentally sustainable approach. Sources of resistance are reported from both cultivated species, Arachis hypogaea, and inter-specific derivatives. Spatial distribution and sensitivity of pathogen to environmental factors pose challenges to field evaluations. Although different methods of phenotyping are available, progress in breeding stem rot resistant cultivars is slow, given the challenges in using these phenotyping tools to identify quantitative disease resistance loci. Recently developed oxalic acid assay (OAA) is a robust method to distinguish plants that can easily succumb to this pathogen. Attempts were made to understand the biochemical and anatomical mechanisms and to identify genomic regions contributing towards resistance to stem rot disease. This review provides an overview of stem rot disease in groundnut, with a focus on host resistance and its application in breeding resistant cultivars.
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