In vitro culture of polyembryonic wasp embryos

在50多种改良的MGM-450培养液上，筛选出适合于多胚蜂2-细胞胚胎培养的培养液。牛血浆白蛋白水平超过I%是胚胎发育到完整桑椹胚所需的培养液成分。卵清蛋白和刀豆蛋白对胚胎的发育也有一定的促进作用，而乳清蛋白则对胚胎发育有一定的不利影响。将MGM-450培养液中的碳水化合物和矿物质分别改成0.2 5%蔗糖和D-20‘S矿物质后，胚胎发育成桑椹胚外的多胚种是必需的。外源保幼激素(JH)支持胚胎发育为多胚种，这是多胚性昆虫特有的发育事件。我的勃起能力最强！紧随其后的是‘H11’和‘H11’。另一方面，20-羟基蜕皮激素不起作用。氨基酸组成对培养2-细胞胚胎至多胚种也很重要，在几种昆虫细胞培养液中，以MGM-450的氨基酸组成最合适。添加胎牛血清可提高多胚体形成率，在桑椹胚期开始培养时，白蛋白和保幼激素的作用不明显，在上述两种MGM-450或改良的MGM-450培养基中，80-90%的桑椹胚发育成多胚体。

Media suitable for culturing the 2-cell embryos of a polyembryonic wasp, Litomastix maculata, were exploited on more than 50 modified MGM-450 media. Bovine plasma albumin levels of more than I % was required as a component of the medium for the embryos to develop up to the complete morula. Ovalbum in and conalbumin also supported some development of the embryos, whereas lactalbumin was rather detrimental. The modifications of MGM-450 medium by changing the carbohydrates and the minerals to 0.2 5 % suct-ose alone and D-20's minerals, respectively, was required for the embryos to develop into Polygerms beyond the morula stac, . e. Experiments on the effect of supplementing- : the medium with insect hormones indicated that exogenous juvenile hormone(JH)supported the development of embryos into polygerms, which was a developmental- event specific to the polyembryonic insects. JH I was the most e erective !iorinone followed by 'H 11 and 'H Ill. On the other hand, 20-hydroxyecdysone did not. The composition of amino acids also was important for culturing 2-cell embryos up to polygerms ; amino acid composition of MGM-450 medium was the most suitable among those of several insect cell culture media. Supplementation of fetal bovine serum into the medium caused the higher percentage of Polygerm formation.There were not clear effects of albumin and juvenile hormone where the culture was started at the morula stage ; 80-90 % of morulae cultured in either MGM-450 medium or modified MGM-450 medium mentioned above developed into polygermis.