Effects of the main cultivar, component factors and yield potentialities of spring wheat on grain yield in Xinjiang.

[Objective and Method]Tnis research was carried out to analyze yield potentialities and the effect on grain yield with the main cultivar of spring wheat in Xinjiang to provie the theoretical bases for wheat breeding.Yield potentialities and grain yield of four leading spring wheat varieties and 3 new spring wheat varieties were studied.And yield in practice and yield potentiality were compared.[Result]As the change of sping wheat varieties,yield in practice and yield potentiality were both increased remarkably,grain weight of the main spike,Grains of the main spike,1000-seed weight and harvest index were improved significantly.Plant height was remarkly reduced.Maturity phase came ahead of time [Conclusion]The main point of breeding spring wheal in Xinjiang is to improve grain weight of the main spike,at the same time,to increase grains of the main spike,to enhance harvest index,to stabilize the 1000-seed weight and to keep the plant height in 85-90 cm.