南阳盆地小麦高产成因分析及育种对策OA

In order to explore the key factors of wheat yield formation in Nanyang Basin and guide the breeding of new high-yield varieties,the resistance of stripe rust and leaf rust,main agronomic traits and parental origin were investigated from 24 regional test varieties(lines)of Huanghuai southern section of Northwest A&F University in 2022,the most productive year in Nanyang wheat area in recent 30 years.Among the 24 varieties(lines),21 showed high resistance to stripe rust,and 3 showed moderate resistance.Six showed high resistance to leaf rust,and 13 showed moderate resistance.The average yield of 24 varieties(lines)was 9 687.45 kg/hm2.The variation coefficient of basic seedlings was the highest(6.57%),followed by the variation coefficient of panicle number(5.51%),grain number per panicle(5.33%),maximum tiller number(4.33%),1 000-grain weight(3.87%),and the variation coefficient of bulk density was the lowest(0.41%).Tracing back the parental origins of these varieties(lines),Zhoumai 18,Xinong 979,Zhengmai 366,and Xinong 822 were directly used with high frequency.The wheat varieties Zhou 8425B,Zhoumai No.9,Xiaoyan No.6 and their sister lines,and Zhoumai 16 were indirectly used with higher frequency.Through path analysis of yield and its components(panicle number,grain number per panicle,and 1 000-grain weight),the direct path coefficient of panicle number on yield is the largest,followed by grain number per panicle.The maturity period of 19 yield-increasing varieties(lines)shows a highly significant positive correlation with heading date.Panicle number has a highly significant positive correlation with basic seedlings and a significant positive correlation with maximum tiller number.Grain number per panicle is highly significantly positively correlated with maturity period,but highly significantly negatively correlated with panicle number and significantly negatively correlated with maximum tiller number.1 000-grain weight is highly significantly negatively correlated with both basic seedlings and panicle number.Plant height shows a significant positive correlation with heading date,a significant negative correlation with panicle number,and a highly significant positive correlation with grain number per panicle.The emphasis of breeding for high yield in Nanyang wheat area is panicle formation number,followed by the number of grains per panicle.Appropriately early heading reduced plant height and then increased panicle formation number,appropriately increased plant height and delayed ripening increased grains per spike.