Scientists at the West Bengal State University have found 19 unique and highly aggressive variants of Phytophthora infestans, a microorganism that causes late blight disease in potatoes, causing them to shrink from the outside and to rot from the inside. A rapidly evolving pathogen from Europe may be the downfall of India’s yield of potatoes, an essential staple crop that also fetches a good income for millions of farmers.
The pathogen population diversity, studied in eastern and north eastern India, was found to be highest in areas near international borders with Bangladesh and Nepal. Both these countries regularly import potatoes from outside.
Earlier, a 2012 study by the Bengaluru-based Indian Institute of Horticultural Research had found European 13_A2 pathogen imported with consignment of potatoes from Europe and UK to be responsible for late blight outbreaks in parts of south India.
These variants are from the lineage of the European 13_A2 genotype and were responsible for the 2013-14 epidemic of late blight in West Bengal that shrank the potato yield by 8,000 kg per hectare, resulting in many indebted farmers ending their lives.