家蚕全龄人工饲料育半化蛹发生研究

STUDIES ON THE OCCURRENCE OF INCOMPLETELY EXUVIATED PUPA OF SILKWORM(BOMBYX MORI L.)FEEDING ON ARTIFICAL DIET

家蚕全龄人工饲料饲育的现行二化性４眠杂交种和原种，其幼虫期的眠起、生长及结茧均能正常进行，但化蛹期半化蛹较普遍发生。杂交种２回育Ⅰ区显著高于２回育Ⅱ区和３回育区，日×中品种高于中×日品种，雌蚕的发生率高于雄蚕；日系品种显著高于中系品种。半化蛹发生率的高低，与给饵回数有着密切的关系，半化蛹多数可变态为半化蛾，但不能交配和产卵。在饲料中添加适量抗氧化剂或在５龄期２回以上给饵，可有效防止半比蛹的大量发生。

While artificial diet was used to feed the commercial bivoltine four-molter hybrid and parental races,the larvae's molting,developing and cocooning could advance nor-mally whereas incomplete pupation occurred fairly frequently in the pupation stage.Inrearing of the hybrid silkworms,it was found that occurrence of incomplete pupationin plot I fed twice a day was significantly more frequent than that in plotⅡfed twice aday and in other plots fed thrice a day, that of varieties of Japanese strain ×Chinesestrain was more frequent than thOse of Chinese strain×Japanese strain,that of femalesilkworms was higher than male silkworms,and thatof varieties of Japanese strain wasmore likely to occur incomplete ptipation than those of Chinese strain,The occurrence ofincomplete pupation was closely related with the number of feedings a day.Most of thesemi-pupae could emerge and form semi-moths. Yet they could not copulate and layeggs. Adding suitable amount of anti-oxidant in the diet or feeding more than 2 times aday in the 5th instar could effectively prevent the heavy occurrence of incomplete pupa-tion.