SHARMA, P LGULERIA, PRANSHU2020-01-062020-01-062019-12http://krishikosh.egranth.ac.in/handle/1/5810139655ABSTRACT The present investigation entitled “Biocontrol potential of Neochrysocharis formosa (Westwood) against Tuta absoluta (Meyrick) in tomato” was conducted during the year 2018-2019 at Dr. Y S Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh. Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is one of the most destructive pest of tomato throughout the world. In the present study biocontrol potential of N. formosa (Hymenoptera: Eulophidae) against this pest was studied. N. formosa attacked first three instars of T. absoluta with highest parasitism (46%), host feeding (15%) and host killing (61%) in the second instar. Developmental time from egg to adult, male longevity, female longevity and fecundity of the parasitoid on different host instars varied from 16 to 16.8 days, 9 to 10.4 days, 27.3 to 30.4 days and 11 to 45.6 eggs/female, respectively. Gross reproductive rate, net reproductive rate, innate capacity of natural increase, true intrinsic rate of increase, true generation time, finite rate of increase, doubling time and weekly multiplication rate varied from 5.11 to 3.48 females/female, 4.37 to 19.07 females/female, 0.0499 to 0.1272,0.0557 to 0.1293 females/female/day,21.91 to 25.43 days, 1.06 to 1.14 females/day,5.37 to 13.15 days and 1.49 to 2.48 times, respectively. Gross kill rate, net kill rate, innate capacity for host kill, true kill rate, finite rate of host kill, weekly kill rate of the parasitoid varied from 13.84 to 46.16 hosts/female, 11.53 to 27.42 hosts/female, 0.0932 to 0.1417, 0.1025 to 0.1474 hosts/female/day, 1.13 to 1.21 hosts/day, 2.27 to 2.97 times, respectively. The parasitoid exhibited Type II functional response with handling time and attack rate of 4.12 to 11.28 and 0.01 to 0.04, and 2.66 to 7.26 and 0.02 to 0.05 when estimated on the bases of parasitism and total host kill, respectively. Mutual interference (m=0.145-0.404) is N. formosa occurred when foraged in densities from 2 to 8 females per 30 larvae.ennullThesis