矮杆基因对春小麦植株生长发育的影响及对子粒产量的间接作用

利用以春小麦品种ＡｐｒｉｌＢｅａｒｄｅｄ为背景的含有不同矮秆基因Ｒｈｔ１、Ｒｈｔ２、Ｒｈｔ３、Ｒｈｔ１＋Ｒｈｔ２和Ｒｈｔ２＋Ｒｈｔ３的５个近等基因系，研究了不同矮秆基因对小麦生长发育的作用。结果表明：Ｒｈｔ１半矮秆基因显著缩短了小麦植株生长发育进程，促进了地上部干物质积累，加大了旗叶面积和倒二叶面积，提高了单株成穗率，减少了无效分蘖；Ｒｈｔ２半矮秆基因显著增大了倒二叶面积，提高了单株成穗率和穗长，减少了无效分蘖；Ｒｈｔ３矮秆基因显著加大了旗叶面积，但对地上部干物质的积累、单株成穗和穗长均有显著的负向作用；Ｒｈｔ１＋Ｒｈｔ２基因结合没有突出的优势存在：Ｒｈｔ２和Ｒｈｔ３基因结合对有利于提高小麦产量性状的作用均为负向最大；上述３种矮秆基因及其不同的结合形式均有显著的使茎秆矮化的作用。因此认为Ｒｈｔ１半矮秆基因在小麦育种中利用价值较大，Ｒｈｔ３矮秆基因利用价值则较小。

Effects of Different Dwarfing Genes on Development of Spring Wheat Plant and Its Indirect Effect on Grain Yield

The effects of different dwarfing genes on the development of spring wheat plants was studied by using 5 near isogenic lines carrying the Rht1,Rht2 and Rht3 dwarfing genes,singlely and in combination in one genetic background of spring wheat (April Bearded).Results showed that Rht1 semi dwarfing gene could shorten the development process of wheat plant,increase the accumulation of dry matter per plant above ground,enlarge both the flag leaf area and the area of the boot leaf,enhance the spike number per plant,and decrease ineffectual tillers per plant.Rht2 semi dwarfing gene enlarged the area of boot leaf,increased significantly the spike number per plant and spike length,and decreased ineffectual tillers per plant.Rht3 dwarfing gene enlarged flag leaf area,but it showed negative effects on the accumulation of dry matter per plant above ground,spike number per plant and spike length.The combination of Rht1 and Rht2 genes had no significant advantages.The combination of Rht2 and Rht3 genes showed significantly negative effects on the traits which may help to enhance grain yield.All the genes mentioned above and their different combinations had significantly negative effect on plant height.Therefore,it was considered that Rht1 semi dwarfing gene has high value and Rht3 dwarfing gene has low value in wheat breeding.