SCREENING OF SUNFLOWER GENOTYPES FOR RESISTANCE TO HELICOVERPA ARMIGERA HUBNER (LEPIDOPTERA: NOCTUIDAE) IN PUNJAB, PAKISTAN

Twenty diverse genotypes of sunflower viz. a-60, g-5, a-179, a-79, a-9, or-103, or-101, or-100b, or-44b, or-92b, or-102b, h-38, s-278, h-33, a-11, g-53, g-32, a-75, g-55 and g-7 were planted with rcbd lay out. based on average egg count and larval population per 5 plants, three genotypes showing resistance (a-11, a-75, g-53), three showing intermediate (g-7, or-102b, a-9) and three having susceptible response (or-100b, g-5, or-44b) were selected. based on larval population of helicoverpa armigera, the genotype or-102b showed maximum hpsi i.e., 22 percent during 2008, or-100b showed 21 percent hpsi during 2009 and on average of both the study years the maximum hpsi was recorded to be 21 percent on or-100b. thus or-100b proved to be a susceptible genotype. the minimum hpsi was observed to be 5 percent on g-53, during 2008.lower values of hpsi were recorded on resistant genotypes. these genotypes may be used as source of resistance for developing sunflower genotypes resistant to h. armigera.