关键词: 微生态制剂, 微生态制剂, 黄芪多糖, 肉鸡, 鸡免疫器官指数, 新城疫, 禽流感

Abstract: The aims are to breed new blast- resistant hybrid rice varieties and to reveal their structural characteristics of high yield. A new hybrid rice variety“Guyou 168”with high yield and blast resistance was bred by crossing‘Gufeng A’(female parent, three-line sterile line bred by Rice Research Institute of Fujian Academy of Agricultural Science) and‘Liuhui 168’(male parent, restoring line). By the plot trial of‘Guyou 168’in Wulin mountainous region, Hunan Province, its biological characteristics were analyzed. The correlation analysis and path analysis between yield and component factors of yield were conducted. The results showed that‘Guyou 168’had the characteristics of high yield, blast resistance, susceptibility to sheath blight, medium-susceptibility to false smut as well as strong cold resistance. The analysis of yield structure indicated that the contribution of spike number per hectare to yield amounted to 34.2%, while that of grain number per spike, 1000-grain weight and seed-setting rate was 27.3%, 18.4% and 17.5% respectively. The contributions of spike number per hectare and grain number per spike to total grain number per hectare came up to 30.6% and 69.2% respectively. The contribution of total grain number per hectare to sink capacity reached 92.9% while that of 1000-grain weight was 6.9%. The contribution of sink capacity to rice yield was 79.5% while that of seed-setting rate was 17.5%. The keys to high yield of‘Guyou 168’are cultivating large spikes, increasing the total grain numbers per unit area and enlarging sink capacity based on the full spikes, as well as improving the seed-setting rate as the guarantee.