Seasonal incidence and management of citrus whitefly (Dieleurodes citri A.)

Seasonal incidence of whitefly on citrus, recorded during 1^st to 52^nd meteorological weeks (MW) of 2013, indicated that its population was high from first week of January to second week of March (1^st to 11^th MW) and third week of October to last week of December (42^nd to 52^nd MW). First peak of 11.8 whitefly twig⁻¹ occurred during 4^th MW and natural enemy population too was the highest (5.7 lady bird beetles twig⁻¹) during the same time indicating positive interaction between sucking pest and predators. Seven neonicotinoids viz., clothianidin 50 WG, acetamiprid 20 SP, dinotefuran 20 SG, nitenpyram 10 WG, thiacloprid 21.7 SC, thiamethoxam 25 WG and imidacloprid 17.8 SL were tested for their comparative efficacy against whitefly on citrus. The pooled data on incidence of whitefly (No. twig⁻¹) influenced by the insecticidal treatments during two seasons revealed that the surviving populations of nymphs and adults in all the insecticidal treatments were comparatively low, indicating that these insecticides were significantly effective. Minimum whitefly population was observed on the plants treated with dinotefuran followed by clothianidin and nitenpyram (6.36, 6.40 and 6.44 whitefly twig⁻¹, respectively) which were statistically at par with each other whereas thiamethoxam and imidacloprid were less effective (8.25 and 8.30 whitefly twig⁻¹).