Studies On The Biology, Ecology And Rearing Technique For Tenebrio Obscurus L. (Coleoptera Tenebrionidae)

The dark mealworm, Tenebrio obscurus Fabricius.,is a cosmopolitan pest of agricultural produce.But there is little information available on so many aspects of this pest.So we went through with experiments in lab,by which studied the rearing method,biology,and population ecology,etc.Tenebrio obscurus F. has one generation a year in Shandong Province.The results showed that the stages of eggs,larves,pupae were 6.47days,215.46days,8.73days respectively. The larve had 12～22 instar,mostly 14～15 instar.The growth and development of Tenebrio obscurus F. were observed at seven constant temperatures.The results showed that the development rate fastened with the rise of temperature within 17℃～32℃. Respectively ,the lower thermal thresholds for eggs,larvae,pupae was 11.36℃,7.53℃,11.23℃,and the effective accumulated temperature for eggs,larvae,pupae was 112.46day-degree, 1724.70 day-degree,104.1842 day-degree.Thefecundity remained relatively high at 17℃,about 90.06 eggs/female,low at 32℃,only 29.00 eggs/female.Calculated the start temperature and valid cumulative temperature by three methods,such as linear regression method,weighted method,and straight-way optimum method.The results showed no significant difference.The cost is a significant factor to mass rear Tenebrio obscurus F.. Five treatments were used to rear Tenebrio obscurus F. at 250～450 per rearing tray for evaluating the different rearing density.The result showed that it was unsuitable to the growth and development of Tenebrio obscurus F. at too high or too low,300/tray and 350/tray were the excellent rearing density relatively.Effect on the grow-development of Tenebrio obscurus F. cleaning feces in different interval was studied.The result showed that there was not significant differende in the mean larval stage,larval survival rate,emergence rate when the temperature is not more than 30℃.So it is unnecessary to clean feces frequently.