Genetic Analysis Of Sch Gene And Applied Research On Silkworm Breeding

1 Effects of environmental factors on the expression of gene sch during incubation stage.It has been widely concerned since Pan Qingzhong (1992) found that the embryo of sch homozygote had lethal effects when it was incubated under high temperature and low humidity. This discovery suggests that gene sch has a promising application in the sex control of silkworm. To make use of gene sch effectively, it is necessary to make a systematic research of the environmental factors on the expression of gene sc/i.(1) The influences of temperature, humidity and treating time on the expression of gene schThree temperatures (32C, 35~C, 38~C), two humidity (60%, 85%) at four time points (24hours, 48hours, 60hours, 72hours) were set during the trachea colouring stage. Each treatment was repeated seven times. Variance analysis indicated that there were significant differences in the total hatching rate between varieties, temperatures, humidity and time points. There were remarkable differences in the interaction of variety and temperature and variety and treating time. But there was no notable differences in the interaction of varieties and humidity. It reflects that the effects of humidity on XiafangXQiusch?s total hatching ratio are the same as Qiubai>