Study on infestation new elite cotton to important sucking-pest

Cotton varieties commonly in planted area have major sucking pests such as Thrips tabaci, Aphis gossypii, Bemisia tabaci, Asymmetrasca decedens. This project was conducted by 6 treatment with 4 replications as randomized complete block desing in Hashem Abad research station in part without spraying the dimension of 80 Χ 30 m during in 2012-2013 years. Sampling of the various stage of sucking pest with regular weekly visits on10 randomly selected plants from each plant 3 leaves total 30 leaf sucking pest counted and recorded in tables at the end of the season. Based on this study had composite analysis of variance indicated, that new elite yield trials, SKT-133 hybrid with 5747 kg/ha maximum yield and TBL-80 hybrid with 5160 kg/ha had minimum yield. Thrips population in Golestan cultivar and SKT-134 hybrid with 0.243 and 0.235 had the highest infection rate in the number of thrips per leaf and N2G80 hybrid and Sahel cultivar respectively with densities of 0.178 and 0.170 had lowest number of thrips per leaf were. Contamination of the tested varieties of cotton aphid population SKT-134 hybrid with density 132.88 aphids per leaf has the highest and SKT-133 hybrid and Sahel cultivar, 94.25 and 92.88 aphids per leaf with minimum of infection rate respectively. Contamination of the tested of varieties of cotton whitefly on SKT-134 hybrid density 90.38 per leaf number the highest infection rate and SKT-133 hybrid and Sahel cultivar, respectively with 72.88 , 72.63 on leaf number was the lowest infection rate. Contamination of cotton cultivars to green leafhopper population, N2G80 hybrid density with 10.500 leaf hoppers in cotton leaves has the highest infection rate, Sahel and Golestan cultivars respectively with a density of 8.875 and 7.000 leaf hopper numbers were the lowest infection rate.