Abstract
Field trials were conducted in randomized completed block design with three replications for the screening of five cultivars of groundnut (BARD-92, 699, 479, BARI-2000 and Golden) against aphid (Aphis craccivora). It was observed that BARD-699 cultivar showed comparatively high resistance with minimum aphid population (4.60 per leaf) and leaf infestation (22%) at 110 days after treatment (DAS).Whereas, the cultivar BARD-479 was found to be highly susceptible with maximum aphid population (8.50 per leaf) and leaf infestation (55%) at 110 DAS. The peak population of A. craccivora was recorded 110 DAS (May-June). The order of cultivar resistance against aphid population and leaf infestation during the whole crop duration was BARD 699 < BARD 92 < Golden < BARI 2000 < BARD 479. Aphid showed significantly positive correlation with maximum temperature for BARD-92 and for negative correlation BARI-2000 cultivars. Minimum temperature however showed significant positive correlation with aphid for BARD-92, Golden, and BARD-699 cultivars. Aphid had significant positive correlation with relative humidity for BARD-479 and Golden cultivars. Whereas, rainfall had negative correlation with aphids on BARD-479, BARI-2000, BARD-92 and BARD-699 cultivars. Consequently, based on the aphid density and leaf injuries on plant, BARD-699 was more resistant and BRD-479 highly susceptible cultivar.