株行距对小麦旗叶氮素代谢及籽粒蛋白质含量和产量的影响

Row Spacing and Plant Spacing on Nitrogen Metabolism in Flag Leaves and Grain Protein Content of Winter Wheat

为了明确小麦高产栽培的合理空间布局模式，在大田高产栽培暑件下研究了行距与株距配置对花后旗叶氮素代谢及籽粒蛋白质含量的影响。结果表明，小麦旗叶氮含量和硝酸还原酶（NR）活性随籽粒灌浆进程逐渐下降，而谷氨酰胺合成酶（GS）活性呈单峰变化。在整个灌浆期，随着行距与株距比例（行株比）增加，旗叶氮含量呈降低趋势，行株比为6的处理（RP2）旗叶氮含量在花后21d以后优势明显，表明行株比例配置合理。不同时期旗叶NR活性均以RP2处理最高，其次是行株比为1．5的处理（RP1），行株比过大则NR活性降低。旗叶GS活性在花后0～7d以行株比为6和10．5（RP3）的处理较高。自花后14d以后不同处理间表现为RP2最高，其次为RP1和RP3，行株比为15的RP4处理最低。考察最终蛋白质含量及籽粒产量，不同行株比处理间差异为RP2〉RP1〉RP32〉RP4，RP2处理的行株比适宜．蛋白质含量和产量均显著高于其他处理，空间布局最为均匀的RP1处理也具有较好的效果。

Field plot experiments were carried out to examine the effects of row spacing and plant spacing on nitrogen metabolism of flag leaves and grain protein content in winter wheat on the farm of Henan Agricultural University during 2005-2007. Four ratio of row spacing to plant spacing with 1.5（RP1）, 6.0 （RP2）, 10.5（RP3） and 15.0（RP4） were respectively arranged in a randomized block design with three replicates. The results showed that N content and NR activity in flag leaves decreased gradually with the process of grain filling, GS activity tended to single peak curve. The N content of flag leaves was increasing with decreasing ratio of row spacing to plant spacing in whole filling stage, with obvious superiority for 6 of ratio of row spacing to plant spacing in later filling stage. It reveals that a suitable combination of row spacing and plant spacing could effectively improve conditions of wind and light, promote N absorption and transportation. The NR activity of flage leaf in RP2 treatment was the highest in filling stage, with next for RP1 and steadily decline for ratio of row spacing to plant spacing over 6. The GS activity of flage leaf in RP2 and RP1 treatments were higher during 0-7 days after anthesis, and the GS activity in RP2 was the highest after 14 days after anthesis with next for RP1 and RP3, the lowest for 15 of ratio of row spacing to plant spacing. The protein content, grain yield and protein yield of RP2 treatment were the highest with harmonizing yield structures and N absorption and transportation, and increased significantly protein content and grain yield, with better treatment of RP1 for increasing yield and improving quality. Therefore the optimum distributing form for winter wheat was to reduce row spacing, enlarge plant spacing and keep suitable ratio of of row spacing to plant spacing.