THE IMPACT OF SOME PHYSIOMORPHIC CHARACTERS OF SUGARCANE GENOTYPES ON THEIR RESISTANCE AGAINST SUGARCANE PYRILLA, Pyrilla perpusilla Wlk. (Lophopidae: Homoptera)

Field trials were conducted in the research area, directorate of sugarcane, ayub agricultural research institute, faisalabad to study he physio-morphic characters of sugarcane resistance to the sucking pest pyrilla perpusilla. twenty genotypes of sugarcane were tested for their resistance susceptibility against p. perpusilla, as a preliminary screening experiment, during 2006. based on the population-density count, 3 genotypes, viz., hsf- 240, cpf-243 and s-2002-us-114 showing resistance responses, 3 genotypes viz. cphs-35, s- 2003-us-394 and s-2003-us-623 showing susceptible trends and 3 genotypes viz. s-2003-us-809, s-2002-us- 140 and s- 2002-us-104 exerting intermediate trends against the pest under test were selected for the final screening trials during 2007.the genotype s-2003-us-623, was found to be comparatively susceptible; whereas, hsf-240, showed resistance responses. the leaf-width and cane length showed a positive and significant correlation whereas the leaf-spine density had a significant negative effect with pest-population. the leaf- length and cane- diameter did not show a significant correlation with the pest population.