Biological Studies on Potato Tuber Moth Phthorimeae operculella (Zeller) Lepidoptera : Gelechiidae

Abstract

The shortest life cycle was 34.8 days at 25 oC with relative humidity about 65 + 5% , while the longest life cycle was 57.8 days at 18 oC with same relative humidity . Egg 10.40 , 5.20 days , the pre-ovipositor period 2.60 , 4.20 days ; the longest ovipositor period 14.60 , 8.0 days , the post ovipositor period were 8.20 , 6.80 days , the number of deposited eggs by one female was reached 76.0 , 151.0 eggs , the hatching percentage 86.8 , 90.0 % respectively . The first instar larvae period was 5.0 , 4.0 days , the second instar larvae period was 5.0 , 3.2 days , the third instar larvae period was 4.0 , 3.0 days , Fourth instar larvae period was 9.0 , 4.4 days , the population percentage 25 , 21% ; the pre-pupal period was 5.60 , 1.80 days , the pupal period was 14.60 , 10.60 days ; the mergency percentage was 80 , 90% ; the female life period was 27.0 , 15.0 days , the male life period was 14.2 , 13.0 days respectively. The result was indicated that the long of egg was 0.48 mm, the width of egg was 0.28 mm, the long of the fourth instar larvae was 12.8 mm, the head capsule width was 0.58 mm, the width of the fourth instar larvae was 1.35 mm, the long of pre-pupal was 5.96 mm, the long of male pupa 6.6 mm, the long of female pupa was 6.7 mm, the male long was 7.8 mm, the female long was 8.2 mm, the distenguesh between male pupa and female pupa depending upon abdomen length was 7.8 mm, the female length was 8.2 mm.