Laval mortality of Protaetia brevitarsis in accordance with the different incubation conditions

Abstract

This study was carried out to determine whether different incubation conditions can affect the larval mortality of Protaetia brevitarsis. In addition, it was carried out to obtain information about the oviposition pattern of P. brevitarsis. P. brevitarsis that was used it the study was a new‐born adult. Adults rearing condition was as follows; temperature 25°C∼27°C, long‐day length (16L:8D), and relative humidity 80%. Larvae were reared at 25°C∼27°C temperature and 80% relative humidity. A total of four types of incubation conditions was designed. First type is the 50 eggs arranged at regular intervals on sawdust (E1). Second type is the 50 eggs put together in the center (E2). Third type is the shift out sawdust and put out adults of P. brevitarsis then put a new cage (E3). Last, lured with bait and put out adults, then put in a new cage (Control). Two weeks later, cages were checked for larval mortality. All of the cages were checked once a week. Types of collect egg are 3. First, don't collect eggs, just lured adults with bait (Control). Second, collect eggs (R1). Last, sift out adults using sieve (R3). Control and R3 eggs remained in cage. Just R1 eggs were arranged on sawdust in new cage. In this study, just Control 1. (10 times repeat) was finished. And other experimental sets are being carried out. In Control 1., larval mortality is 87%. Adults laid 2597 eggs, total 2259 larvae metamorphosed to pupae. Oviposition pattern is Control 1. (10 times repeat) adults laid 3909 eggs, Control 2. (5 times repeat) adults laid 2257 eggs, R1 (10 times repeat) adults laid 3367 eggs, R2 (5 times repeat) adults laid 2142 eggs. Control 1. is preliminary experiment. So, after finish that experiment, repeat that one more time. Usually, P. brevitarsis laid eggs for approximately 10 weeks. And between 2 to 4 weeks, they laid most eggs.