ABSTRACT The present study was carried out throughout two successive years (2019-2021) to conduct a survey of scale insects infesting date palm all over Egypt and an investigation on the major date palm scale insects. The results indicated that the date palm trees were infested by 5 species of scale insects. The seasonal activity of Avidovaspis phoenicis Gerson and Davidson (Hemiptera: Diaspididae) on date palm was studied during 2019-2020 in Giza and Qalyubiya Governorates. The obtained results showed that both nymphal and adult stages have two periods of seasonal activity per year. The 1st period of nymphal activity occurred in autumn season that peaked in early December in both years. The 2nd period of nymphal activity occurred in summer season that peaked in early July in the 1st year and early June during the 2nd one. The 1st period of adult activity was recorded during autumn-winter seasons with one peak in early February in the 1st and 2nd year. The 2nd period of activity was determined during summer season that peaked in early July in the 1st year and early June in the 2nd one. On the other hand, the duration of seasonal activity for both nymphal and adult stages was affected significantly with the tested weather factors. Eight insecticide compounds were evaluated for their controlling activity on the scale insect as well as its parasitoid A. mytilaspidis on date palm in Giza and Qalyubiya during two successive seasons 2019 and 2020. The obtained results revealed that Imidacloprid (Ecomida) has the highest reduction % values for the scale and its parasitoid during the two experimental years. On the other hand deltamethrin (Decis) shows less reduction percentages compared to the scale and its parasitoid during the two successive (2019-2020) years in the two locations.
View Full Article
|