Bionomics of the Lime Blue Butterfly , chilades lajus (Stoll) [Lepidoptera : Lycaenidae)

Abstract

Chilades lajus is an important pest of the leech lime, Citrus hystrix DC. the larvae fed on teh growing shoots, young leaves, and sometimes it bored into the young fruits and flowers. Besides, c. hystrix, it was found that lime blue butterfy larvae could feed on several plants in the genus Cittus. These included the lime (C. aurantifolia), mandarin orange (C. reticulata), pubbelo (C. maxima) and sweet orage (C. sinensis) leech lime was the most preferred host of C. lajus.
Under the experimental condition, C. lajus was reased on young leaves of C. hystrix. It was found that eggs are laid singly on either sid eof young leaves, on the terminal shoots and/or young leaf stalks, but sometimes in pairs are laid together overlapping. The mean for incubation period of egg was 2.26 +- 0.15 days. The average duration of the 5 larval instrars was 1.25 +- 0.07 , 1.32 +- 0.10, 1.55 +- 1.05 , 1.94 +- 0.18 and 2.87 +- 0.24 days, respectively. The mean for the whole larval life was 8.93 +- 0.16 days. On the back of 7 th abdominal segment of this species larvae, with sa small slit, it is th emedial dorsal gland (honey gland). On the segment behind this gland is a pai of extensile glands which is everted when the larvae are disturbed, armed at the tip of extensile gland with bristles. Pupation took place on the average 6.34 +- 0.57 days. The mean length of the whole cycle was 17.53 +- 0.59 days.
Laboratory studies found that adult female of lime blue butterfly survived for 10 to 14 days with a mean of 11.67 days when fed on a diluted honey solution while males survived for 7 to 9 days with a mean of 7.47 days. The number of eggs that each female could lay letween 76 to 127 eggs, with mean of 99.27 eggs per female.