اختبار فعالية مستخلصين نباتيين و مبيد كيميائي في الحقل لمكافحة حشرة دوباس النخيل Ommatissus Lybicus De berg (Homoptera : Tropiduchidae)‎

الملخص EN

Dubas bug represents the most economic importance pest on date palm in Yemen , especially in eastern coastal area(Coast of Hadramout , Shabwa and Al-Mahra).

National control campaigns carried out annually by using ground application of conventional chemical pesticides including pyrethriod insecticides.

Many of which are effective but simultaneously kill beneficial insects like parasites , predators and bees.

Even though Dubas bug can be adequately controlled with chemical insecticides, the cost availability, health and environmental risks impose serious limitations on the use of conventional chemicals .Recently Dubas bug has also acquired reduction in susceptibility to insecticides that have been previously effective.

Therefore, an alternative approach is urgently needed for controlling this devastating pest.

One possible solution is the use of natural bio-rational plant extracts that could be safe, sustainable, eco-friendly and effective control measure and to achieve this approach , field experiment was conducted in RCB design in four replicates for three seasons2007-2008, 2008-2009 and 2009-2010 for spring generation of dubas bug at The emergence of second and fourth instar nymphs to determine the efficiency of neem seed powder extract at a rate of 100g/l water and Cleome droserifolia Delil methanolic extract at rate of 3ml/l water comparing with Desis (Deltamethrin insecticide) and water spray .Data statistically analyzed using Costat program at p= 0,05.The results of first season show a significantly lower population a day and one week after spraying in all treatments compared with control, however effectiveness of the neem Azadirachta indica Juss extract was significantly higher and reached 84% , compared with C.

droserifolia extract which reached 51%,while the effectiveness of water spray was 29%.but the most effective was Desis insecticide which gave 94,8% .

Second season all treatments decreased Dubas population significantly.

However neem extract efficiency on nymphs and adult reached 78% and 50% respectively.

Results of third season confirms that all treatments significantly reduced the nymphs population after spraying ,and neem extract showed significantly higher effectiveness than C.

droserifolia extract.

Trial for three seasons concluded that neem extract could be used in integrated Dubas bug management .