author(s)
Niranjanadevi Jeevanandham, Murugan Marimuthu, Senthil Natesan, Karthikeyan Gandhi and Sathiyamurthy Appachi

abstract
Present studies were conducted on chillies Capsicum spp against whitefly in field and greenhouse screening. Forty five chillies accessions were subjected to field screening against whitefly, Bemisia tabaci. Varietal resistance is further evaluated in the greenhouse condition by studying the categories of resistance on whitefly. Accessions selected as ‘‘promising’’ for resistance (low whitefly populations) and susceptible accessions were reevaluated at greenhouse condition. Ten accessions of Capsicum were screened against whitefly, under greenhouse condition for categorization of the mechanism(s) of resistance. Accessions P2, P4, ACC1 and ACC12 were found to be less preferred for adult settlement, whereas accessions P1, P3, P5, ACC10, ACC26 and ACC27 were the most preferred one. In resistant accessions of chillies accumulative reduction in pest population was noticed by reduced rate of reproduction and increased developmental period. The number of eggs laid and the percentage of nymphal and adult emergence were low on resistant accessions viz., ACC12 (4.33 no of eggs /pair/leaf, with 76.92 % hatchability), P2 (5 no of eggs /pair/leaf, with 80% hatchability), P4(5.33 no of eggs /pair/leaf, with 81.25 % hatchability) and ACC1(4.67 no of eggs /pair/leaf, with 85.71 % hatchability). In population build-up study, significantly lower numbers of progeny were observed on accessions ACC12 (0.33 adults/pair/leaf), P2 (0.67 adults/pair/leaf),) and ACC1 (0.67 adults/pair/leaf),). Conversely, the number of progeny produced by F₂ was significantly greater on ACC 10 (7.93 adults/pair/leaf)). The accession P2, P4, ACC1 and ACC12 has displayed strong antixenotic and antibiotic effect against whitefly, Bemisia tabaci.