Resistance to bacterial wilt of potatoes in diploid Solanum microdontum Bitt.

Bacterial wilt caused by Pseudomonas solanacearum Smith is one of the most lethal bacterial diseases. It limits successful cultivation of crops like potato, tomato brinjal, chillies, groundnut, tobacco etc. in most of the warm subtropical regions of the world (5). In India this is one of the most serious disease in major potato growing areas (10) and causes 10–70% yield losses.

Many attempts have been made to identify usable and acceptable sources of wilt resistance in potatoes (1, 7, 8, 10, 11, 12). Tourston and Lozano (11) reported resistance in S. phureja which was later exploited in breeding (9) and resistant varieties developed were released in South America (3). In screening with the Indian isolates of the pathogen, however S. phureja proved susceptible (4).

Therefore, search for resistance to the disease was started in 1973 in clones of Solanum species and Tuberosum accessions maintained in the germplasm collection at the Central Potato Research Institute, Simla. The results are reported in this paper.