The Presence of Whitefly Bemisia tabaci, and Thrips Thrips tabaci on Different Cucumber Plant Hybrid Varieties in the Field Conditions

Abstract

The study was conducted to determine the susceptibility of different cucumber hybrid varieties (Jumbo Green, Ghazeer, Nefer, and Sahem) to sucking insect pests, onion thrips Thrips tabaci Lind., and tobacco whitefly Bemisia tabaci Genn., during the summer of 2018 season in the experimental fields of College of Agriculture, University of Baghdad, Iraq. The results showed that the infestation of cucumber varieties with sucking pests onion thrips T. tabaci and tobacco whitefly B. tabaci occurred on all varieties during the entire month of July. Nefer and Sahem varieties were more susceptible to high infestation by the whitefly adult, where the average was 5.21 and 5.05 adults per leaf, respectively, compared with the Ghazeer and Jumbo Green varieties, where the average was 4.06 and 4.02 adults per leaf, respectively. At the same time, the nymph average of whitefly was 55.80 and 55.20 nymphs per leaf on Ghazeer and Jumbo Green, respectively, followed by Sahem and Nefer varieties, which were 47.80 and 38.10, respectively. The average of thrips nymphs was recorded on all varieties, which were 4.52, 3.57, 3.06, and 2.96 nymphs per leaf on Sahem, Nefer, Ghazeer, and Jumbo Green, respectively. During July and early August, the green lacewing Chrysoperla sp., parasitoids Ahidius sp., and coccinellids like ladybird Coccinella sp. were found to be linked with whitefly and thrips pests on all varieties.