Evaluations of Three Bacillus thuringiensis Against Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in Egypt

The role of three microbial control agents Bacillus thuringiensis Diple (2X) ; B. t kurstaki HD-73 and B. t kurstaki HD-234 were tested against tomato pinworm Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), which infect plants under laboratory, green house and field conditions. The results showed that under laboratory conditions, the LC50 recorded were 140, 109 and 90 Ug/ml Ug/ml when T. absoluta treated with different concentrations of B. t. B. t kurataki diple (2X), B. t HD-234, and B. t HD-73, respectively. Under green house effect LC50 recorded 166, 122 and 102 Ug/ml for Bacillus thuringiensis Diple (2X), B. t kurstaki HD-73, , and B. t kurstaki HD-234 ; respectively. In the field, results show that, after 50 day of the application the means number o infestations were scored significantly decreased to 11.1712, 7.710.8, 18.211.2, individuals for the corresponding B. t as compared to 26.511.34 individuals in the control After 90 days of the post applications of the bacterial varieties, the means number of infestations significantly decreased to 112.211.9, 10.68.8, 15.210.7 as compared to30.6 10.8 individuals in the control. At the end of the experiment t120 days the corresponding mean number of the infestation 14.511.5, 1 1.413.5, 17.89.9 as compared to35.412.3 individuals. The weight of the tomatoes after the harvest scored the highly significance weight reached to 4916 42.50, 4131 34.33, 3123 41.28, Kg/ feddan in the area treated with Bacillus thuringiensis Diple (2X), B. t kurstaki HD-73, and B. t kurstaki HD-234, respectively as compares to 2631 36.80Kg/fesddan in the control in EL-Esraa farm (Nobaryia) during season 2013. In El-Kassaseen (Ismailia) during season 2013 the corresponding treatmedts areas scored a highly yied recored to, 3718 40.30, 3718 40.30and 587969.33 Kg/ feddan as compared to 188180.54Kg/ feddan.