Resistance Screening of Groundnut Advanced Breeding Lines against Collar Rot and Stem Rot Pathogens

Forty groundnut advanced breeding lines along with susceptible checks JL-24, J-11 and TMV-2were used for collar rot (Aspergillus niger) and stem rot (Sclerotium rolfsii) disease screening.Based on the per cent number of plants affected by the collar rot pathogen, the advancedbreeding lines were categorized into four groups. The lines present in group I (Resistant) havingu003c 15% incidence, group II (Moderately resistant) having 15.1 to 30%, group III (Susceptible)having 30.1 to 45 % and group IV (Highly susceptible) having u003e 45% incidence. Similarlyamong 40 breeding lines only three lines (ICGV86699, ICGV91114 and ICGV 89280) haveshown stem rot disease reaction below 3 (up to 25 % plants were symptomatic) and considered tobe moderately resistant to stem rot pathogen. The advanced breeding line ICGV99058 hasrecorded a disease reaction of 5 scale (u003e 50 % of the plants symptomatic) equal to thesusceptible checks which is considered to be highly susceptible to stem rot pathogen.