Impact of plant phenology of various wheat genotypes on aphid population

Studies of aphid population on different wheat genotypes were carried out at NIFA, Peshawar. A field experiment having 9 genotypes i.e., IBW- 96079, IBW 96351, IBW- 96379, IBW 96172, IBW 96362, IBW-96364, IBW 96369, IBW-96405, IBW-96388 and a variety Bakhtawar-92, each replicated four times was laid out in RCB design. The data revealed that aphid infestation started during the 2nd week of February invariably on all the genotypes. The population reached a peak of 4.545 aphids/leaf during the 2nd week of March on all the genotypes. With the maturity of the leaves, the aphids shifted to the ears during the last week of March and disappeared towards the end of April when the ears were almost dry. Mean varietal response was variable, with IBW-96369 infested by the highest (2.45 aphids/leaf) and IBW-96351 by the lowest average population of 1.30 aphids/leaf during the cropping season. The response of the remaining genotypes was intermediate (1.55 to 2.14 aphids/leaf). Mean varietal response regarding ear infestation was non- significant for all the genotypes.