以黄土高原南部半湿润区土垫旱耕人为土为供试土壤进行大田试验,在不同施氮水平基础上,以NR9405、9430、偃师9号、小偃6号、陕229号、西农2208、矮丰3号和商188等8个冬小麦品种为供试材料,研究不同年度、不同农艺性状冬小麦不同叶位叶片在个体产量形成中的作用。结果表明,冬小麦旗叶和倒二叶长度、宽度及其叶面积同时受品种和施氮控制,施氮后显著增加。旗叶和旗叶以下余叶对冬小麦籽粒产量形成起着重要作用。与不去叶处理相比,开花期去旗叶、留旗叶去其余叶、去所有叶对单穗粒数影响不大,各处理粒数变化在32.91~34.95粒/穗之间。但去旗叶后穗粒重有一定程度下降,比对照植株下降8.7%;留旗叶去其余叶和去所有叶处理,分别比对照植株减少18.2%和29.3%;去叶处理对单粒体积的影响与对单穗粒重的影响相一致;去旗叶、留旗叶去其余叶和去所有叶处理单粒重极显著降低,分别比对照下降7.0%、13.3%和25.1%。花后单株叶对产量的贡献大体上在1/4~1/3之间。
A field experiment was carried out with eight winter wheat varieties,NR 9405,9430, Yanshi 9, Xiaoyan 6,Xinong 2208 and Shaan 229,Aifeng 3 and Shang 188,and Eum-Orthic anthrosols for studying the contributions of the leaves of wheat at different positions to the yield formations of its individual at dif- ferent fertilized nitrogen rates in different years and in relation to different wheat agronomic traits. The re- sults showed that the lengths and widths of the flagleaves and penultimate leaves depended on both the va- rieties and nitrogen fertilization and greatly increased after nitrogen fertilization. The flagleaves and the leaves below the flagleaves contributed greatly to the kernel yields of winter wheat;compared with the treatments without leaf removing,removing the flagleaves,keeping the nagleaves anu removing the other leaves, and removing all the leaves at the flowering stage did not affect the kernel numbers per spike, which ranged within 32.91- 34. 95 in various treatments. But after removing the flagleaves, the kernel weights decreased to some extent,by 8.7% compared with those of the control plants ;compared with the kernel yield of the control plants the kernel yields in the treatments of keeping the flagleaves and removing all the other leaves,and removing all the leaves decreased by 18.2% and 29.3% ,respectively. The effects of leaf removing treatments on the kernel sizes were consistent with those on the kernel weights;removing the flagleaves,keeping the flagleaves and removing all the other leaves,and removing all the leaves significantly decreased the kernel weights by 7.0 %, 13.3 % and 25.1% ,respectively. After flowering,the contributions of the leaves of the individual plants made up 1/4-1/3 of their yields.