EFFECT OF THREE CHEMICALS AND NEEM INSECTICIDE AGAINST AUTUMN POPULATIONS OF DUBAS BUG, OMMATISSUS LYBICUS DE BERGEVIN (TROPIDUCHIDUE: HOMOPTERA) IN OMAN

The dubas bug, Ommatissus lybicus De Bergevin is an important pest of date palm, Phoenix dactylifera in Gulf countries, Middle East and north Africa regions. The intensive use of insecticides in Oman to control the dubas bug might lead to resistance. An entomological field study was carried out to test pesticides against dubas bug insect on autumn generation in Al-Batinah region in sultanate of Oman. Four insecticides were used: Decis, Oberon, Mospilan and Nimbecidine (which is neem extract) and the control was sprayed by water only. The number of the nymphs were counted visually on the trees before one day and after 3, 7, 10 and 14 days of the treatments. There were no significant differences between the means of densities one day before treatment for the five used plots. The number of alive nymphs for Nimbecdine (azadirachtin) and for Mospilan (acetamiprid) were the least compared with Dices and Oberon after 10 days of treatments, but without significant differences. Insect densities of alive dubas bug nymphs after 14 days of the applied treatments showed significant differences between the treatments. Mospilan treatments showed the least number of alive dubas bug significantly compared with the other tested pesticides. Overall means within the whole experimental work from three days spraying to 14 days of the same applications indicated that all used pesticides were effective in decreasing the dubas bug population, leading to effective control. However, preferable to spray insecticides when dubas bug nymphs in the fourth instars, or when more than 75% of egg have hatched, treated the dubas bug in autumn generation with the Mospilan insecticide under field conditions is more effected to control this pest and even the Nimbecdine gave low results in the pest control, but it is good to be used in pesticide application programmes, because they are a biological, eco-friend insecticides, less residues and to avoid pesticide resistance.