In search of resistance against late leaf spot in groundnut

Groundnut (Arachis hypogaea L.), also known as peanut, occupies 9 per cent of the world's oilseed area, and contributes close to 5 per cent to vegetable oil production. It is an important crop from the perspective of food and nutritional security of poor small holder farmers in developing countries. Late leaf spot (LLS) disease caused by Phaeoisariopsis personata (Berk. and Curt.) von Arx. is globally wide spread and is the most important foliar disease of groundnut. Reduction in the yield due to leaf spots is largely due to damage caused to the leaves as a result of intense spotting and consequent loss in the photosynthetic area. Resistance to late leaf spot pathogen has been attributed to various morphological, anatomical, physiological, molecular and biochemical characteristics of the host plants. It is essential to understand the basis of resistance operating in the newly identified genotypes and the way in which these are affected by disease development. This knowledge will help to develop cultivars with better resistance to LLS even when the environment favours rapid disease increase.