Pest Management of Ficus Benjamina by Morphological Study of Lepidoptera Bombycidae

Abstract

This study investigates the developmental parameters of Trilocha varians, a species within the Lepidoptera order belonging to Bombycidae family, focusing on their interaction with the weeping fig, Ficus benjamina, a significant agricultural pest in Pakistan. The experiments were conducted at a controlled temperature of 26°C and a humidity level of 65%, simulating conditions relevant to the region. Observations revealed that female Trilocha varians laid 160-270 eggs in 2-6 layers on the dorsal part of the F. benjamina leaves. Interestingly, unmated females also deposited clusters of 15-183 eggs, which did not progress to larvae. The eggs turned black 24 hours before hatching. The incubation period for eggs on F. benjamina was found to be 3.46 ± 1.22 days. The survival rate of T. varians larvae was notably high, likely attributed to prolific reproduction. During the study period, five larval instars were identified, with the last two instars causing the most damage, particularly due to their resemblance to host parts such as bark. Notably, the ninth abdominal section of larvae featured thin, spongy horns. The duration of development for the first, second, third, fourth, and fifth larval instars was 2.44 ± 0.82, 3.56 ± 0.53, 3.72 ± 0.26, 4.54 ± 0.79, and 6.20 ± 0.78 days, respectively. The larvae exhibited boat-shaped and yellow silky characteristics. Upon reaching adulthood, the male and female Trilocha varians displayed distinctive features. The average lifespan for males was 6.23 ± 2.09 days, while females lived longer, with a mean longevity of 10.01 ± 0.99 days. Female forewings exhibited faint reddish-brown streaks on the dorsal side, and their thorax, head, and abdomen were darker reddish-brown compared to males. Adult hind wings were predominantly greyish with reddish-brown outer edges.This research provides valuable insights into the biology and behavior of Trilocha varians and their impact on F. benjamina. Understanding these developmental parameters is crucial for implementing effective pest management practices in agriculture, contributing to the sustainable protection of crops against this significant threat.