标题：EFFECT OF THREE CHEMICALS AND NEEM INSECTICIDE AGAINST AUTUMN POPULATIONS OF DUBAS BUG, OMMA T ISSUS LYBI C US DE BERGEVIN (TROPIDU CHIDU E: HOMOPTERA) IN OMAN
摘要：The dubas bug, 012zz7zati.s'.,su.s' lybicus De Ber- gevin is an important pest of date palm, Phoenix dac- tylg'fera i11 Gulf countries, Middle East and north Af- rica regions. The intensive use of insecticides in Oman to control the dubas bug might lead to re- sistance. An entomological field study was carried out to test pesticides against dubas bug insect on an- tunm generation in Al-Batinah region in Sultanate of Oman. Four insecticides were used: Decis, Oberort Mospilan and Nimbecidine (which is neem extract) and the control was sprayed by water only. The num- ber 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 be- tween the means of densities one day before treat- ment for the five used plots. The number of alive nymphs for Nimbecdine (a7adirachtin) 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 ap- plied treatments showed significant differences be- tween the treatments. Mospilan treatments showed the least number of alive dubas bug sigrrifrcantly compared with the other tested pesticides. Overall means within the whole e.\'pen'1nental work from three days spraying to 14 days of the same applica- tions indicated that all used pesticides were effective in decreasing the dubas bug population, leading to effective control. However, preferable to spray in- secticides when dubas bug nymphs in the fourth in- stars, or when more than 75% of egg have hatched, treated the dubas bug i11 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 progrannnes, be- cause they are a biological, eco-friend insecticides, less residues and to avoid pesticide resistance.
