家蚕保存系统广食性种质的检出与培育

采用终龄起蚕用甘蓝型白菜饷食的办法，对600多个家蚕保存系统进行了广食性检测。不同系统对检测食物的摄食反应差异很大，共在50个品系的饲育区中观察到了取食个体。分别采集摄食个体自交继代，经过筛选，从中建立了10个广食性资源品系。优先对表现优良的GS01进行连续多代复选，获得了摄食率达到或接近100％的蛾区。该系统对人工饲料具有优良摄食性，进行全龄人工饲料育能顺利结茧、羽化；而用同样的人工饲料饲育不取食甘蓝叶的12-010则在l龄中死亡。将显性遗传的GS01广食主基因导入实用品种，进行了广食性基础蚕品种的初步培育。

DETECTION AND BREEDING OF EURYPHAGOUS GERMPLASMS IN PRESERVED SYSTEMS OF SILKWORM (BOMBYX MORI L.)

The last instar silkworms (Bombyx mori L.) of over 600 preserved systems were fed with cabbage (Brassica oleracea var. capitata) leaves after moulting to investigate possible euryphagy present among them. Great differences were noticed among the systems in their ingestion response to the feed studied and individual silkworm larvae were found to feed on cabbage leaves in the feeding batches of 50 races. Such individuals were selected for selfing to produce their offsprings and, as a result, 10 euryphagous races were established through selection. Re-selection was made in successive generations of an outstanding race, GS01, and a batche with an ingestion rate of approximately 100% was obtained. That system proved highly adaptable to artificial feed and succeeded in cocooning and eclosion when fed with artificial feed throughout various growth stages. In contrast, the silkworms of the race 12-010, which did not feed on cabbage leaves, died at the first instar stage when fed with the artificial feed. Preliminary breeding work has been done in developing basic euryphagous races through incorporating the dominant major gene of euryphagy of GS01 into commercial silkworm races.