TRUNK INJECTION WITH NEONICTONIODS INSECTICIDES TO CONTROL THE GREEN PIT SCALE INSECT (PALMAPSIS PHOENICIS RAMACHANDRA RAO) (HOMOPTERA: ASTEROLECANIIDAE) INFESTING DATE PALM IN NORTHERN SUDAN

Small scale field experiments were carried out in Elgaba scheme, and El Golid area during the seasons 2003/2004-2004/2005 to evaluate the efficacy of four systemic insecticides; imidacloprid as Confidor 200SL, Rinfidor 20% SL and Comodor 20% SL and thiamethoxam as Actara 25WG, against the green pit scale insect (Palmapsis phoenicis Ramachandra Rao). A trunk injection technique was used. The insecticide thiamethoxam as Actara 25WG was tested at 6, 8 and 10 g/palm while imidacloprid as Confidor 200SL, Rinfidor 20% SL and Comodor 20% SL were tested at 10, 15 and 20 ml/palm. Irrigation was scheduled every 10 days. A Completely Randomized Design with six replicates (one palm=replicate) was used. The insects (all developing stages) were counted (cm²/leaflet). Eight leaflets from each palm were inspected at biweekly intervals. Dates’ yield and quality were determined at harvest. Residue analysis was carried out on dates, soil and intercropped plants twice (at rutab stage and harvesting).
Results indicated that the % mortality (adult and immature stages) were significantly higher in insecticides treatments than the untreated control. Results of residue analysis indicated that no residues of both imidacloprid and thiamethoxam were detected in dates, soil and intercropped plants when treated with the high doses. The higher doses remained effective throughout the experimental period. Date palm treated with the higher doses of tested insecticides developed normally and the dates reached maturity (ripening) and the yield was increased by more than 70% compared with the untreated control. All insecticides checked termites and many other pests, but did not affect mites. This method of application was found highly economical and safe for the users with minimal environmental impacts.