BIOLOGY AND MORPHOMETRICS OF BACTROCERA DORSALIS HENDEL (DIPTERA : TEPHRITIDAE).

Studies on the biology of Bactrocera dorsalis Hendel revealed that the freshly laid eggs were glistening white to creamish in colour, elliptical gently tapering at one end while it was rounded at the other end and becomes slightly darker towards the time of hatching. The mean length and breadth of the egg was found to be 1.10±0.08 mm and 0.20±0.01 mm respectively. The maggots are apodous with three instars. The first and second instar maggots measured 4.61±0.43 mm and 6.68±0.50 mm length respectively and 0.55±0.094 and 0.92±0.07 mm breadth respectively. First instar maggots were translucent and with very few armatures on the body. Third instar maggots were creamish white to yellowish in colour and measured 8.60±0.48 mm and 1.51±0.17 mm length and breadth respectively. The body of a third instar maggot was highly sclerotised and with a well developed cephalopharyngeal skeleton. Puparium was cylindrical, colour varies from creamish yellow to brown and measured 4.79±0.22 mm length and 1.90±0.16 mm breadth. The duration of egg, first, second, third instar and pupal duration was 1.52±0.40, 2.12±0.43, 2.20±0.33, 4.22±0.32 and 11.22±0.46 days respectively. Pre-oviposition duration was 12.00±1.23 days. The mean length of male and female flies were 5.93±0.22 and 6.28±0.24 mm. Females were longer lived than males with a longevity period of 87.83±5.66 and 104.12±7.05 days of male and female respectively. Adult flies without any food after the emergence lived for 1.54±0.39 and 1.62±0.40 days for male and female, respectively. [ABSTRACT FROM AUTHOR]