不同产量水平小麦的氮吸收利用差异

在土培盆栽条件下，以130份小麦为材料，测定了不同生育时期小麦的干物质量、氮素含量和籽粒产量，将供试品种按籽粒产量由低到高低依次分为I、II、III、IV、V、VI等6类型，研究了各类型氮素吸收利用的差异。结果表明：（1）供试品种籽粒产量差异较大（CV=3316%），氮素籽粒生产效率随籽粒产量水平提高呈增加的趋势(r=02740**)，提高氮素吸收量和籽粒氮素利用效率均可提高籽粒产量。（2）不同生育时期，不同籽粒产量水平类型小麦植株含氮量存在显著或极显著差异，但与籽粒产量的相关性不密切。抽穗期和成熟期植株吸氮量与籽粒产量极显著相关(r=02890**、09175**)。（3）不同生育时期氮素干物质生产效率在类型间的差异均达到显著水平，但其与籽粒产量相关性不显著。提高氮素收获指数和拔节期氮素干物质生产效率均可提高籽粒产量。（4）拔节期-成熟期不同类型间小麦干物质量随籽粒产量的增加而增加，成熟期表现尤为突出。籽粒产量水平较高的品种在拔节期后有较强干物质和籽粒产量形成能力。（5）氮素吸收量和氮素籽粒生产效率是影响籽粒产量的重要因素。

DIFFERENCE OF NITROGEN UPTAKE AND UTILIZATION IN WHEAT CULTIVARS WITH DIFFERENT GRAIN YIELD LEVEL

In order to study nitrogen efficiency of wheat breeding genotype,130 varieties of wheat were used in this study to evaluate their differences in dry matter weight, grain yield, nitrogen uptake and utilization at different growth stage through pot culture experiment. These cultivars were classified into 6 types from low to high grain yield (I,II,III,IV,V and VI).The results indicated that (1) Difference of grain yield of the cultivars was very large(CV=3316%), increase of  N uptake efficiency and NUE of grain yield could increase grain yield. (2) The plants nitrogen uptake significant or maximum significant difference with different level of grain yield at different growth stage, but the correlation between nitrogen uptake and grain yield was not close. The plants absorb nitrogen and grain yield significant correlation at heading and mature stage (r=02890**, 09175**). (3) Nitrogen utilization of dry matter production was significant, but no significant correlation with grain yield with different level of grain yield. Improve nitrogen harvest index and nitrogen efficiency of dry matter production in jointing stage can increase grain yield. (4) Dry matter weight with grain yield increased, especially at maturity after jointing stage. High grain yield cultivars were capable material and grain yield formation ability after jointing stage. (5) Nitrogen uptake and grain production efficiency is the effect of nitrogen is an important factor of grain yield.