Intensification Effort Of Wild Silkworm Attacus atlas L. (Lepidoptera : Saturniidae) Rearing.

Abstract

Wild silkworm Attacus atlas is one of Indonesian native insect which has high potential to be developed. The cocoons are superior compared with others types of silk, so various processed products can be made such as handicraft, clothes and art that has a high economic value. The cocoon retrieval from nature resulting in population decline of A. atlas in nature, therefore intensive indoor rearing of A. atlas with feed and mating management to increase production is necessary. The purpose of this research was to perform intensive effort of A. atlas rearing by examining the mating management and observed the effect of the feeding treatment on the growth of wild silkworm A. atlas. The research was divided into two phases. The first experiment focussed on mating management of A. atlas done by the different length of mating period of 3, 6, 12 and 24 hours to assess its effect on egg performance, including eggs laying period, number of eggs, the average weight of eggs, eggs hatching period and the hatchability. The second stage was the provision of two types of alternative feed (guava leaves and walnut leaves) with a different frequency of feeding (3 and 4 times a day) to observe its influence on larval growth. The results showed that the different of mating duration significantly affected (p<0.05) to number of eggs. The number of eggs of the mating for 6, 12 dan 24 hours was not significanly different for each 225.80 + 24.30 eggs, 245.00 + 50.70 eggs dan 288.40 + 77.63 eggs, significantly different from the number of eggs in mating for 3 hours was 155.60 + 48.75 eggs. The egg hatchability was significantly influenced (p<0.01) by different time mating with means 92.16 + 6.57 %. Percentage of eggs hatchability with mating time of 6, 12 and 24 hours were not significantly different, but significantly different from the time of mating for 3 hours. The different time of mating did not significantly affected (p > 0.05) egg laying period (oviposition) with an average time was 5.00 ± 0.65 days. The result also showed that different time of mating was not significantly different (p> 0.05) to the time of hatching eggs with an average value of 9.80 ± 0.87 days. Moths are mated in different time of mating produced eggs that were not significantly different weighy (p> 0.05). The results at the second research showed that larvae of A. atlas liked both types of the given leaves. Interaction of treatment types of feed and the feeding frequency significantly affected (p<0.05) feed intake, digestibility, digested food, weight gain, diameter increament, mortality and instar period. Difference in feed and feeding frequency significantly affected (p<0.05) the average of larvae’s consumption from instar I to instar IV. Larvae fed with walnut leaf consumpt 0.310 g/larva (instar I) and 0.442 g/larva (instar II) higher that fed with guava leaves (0,279 g/larva; 0.392 g/larva). At the third and fourth instars, larvae fed with leaves of guava has the higher consumption average with 0.967± 0.098 g/larva and 1.211 ± 0.189 g/larva. Digestibility and digested feed were influenced significantly (p <0.05) by feed treatment. At instars I and II larvae that fed with walnut leaves have greater value of digestibility and digested feed than larvae feed with guava leaves while, the opposite happens at the third and fourth instars, larvae fed with leaves of guava has the higher value of digestibility and digested feed. Different feeding frequency also affects digestibility and digested feed. Value and digestibility of feed ingested larvae fed four times a day greater than those fed three times per day Weight gain and body diameter larvae were affected significantly (P <0.05) by treatment. Weight gain and diameter gain of the first and second instar larvae fed with walnut leaves have increament of four times higher than guava. When it get to the third and fourth instar, larvae weight gain fed with guava leaves were higher than larvae fed with walnut leaves. Highest percentage of death occurred in the first instar larvae fed on leaves walnut with three times feeding. Extreme increase of mortality occurred at the third instar and fourth instar. Stadia period also affected significantly (P <0.05) by treatment interaction, especially at instar I.