小麦氮素高效利用基因型的农艺性状及生理特性

为给小麦氮高效型品种选育和栽培调控提供理论依据,采用大田试验,以14份小麦品种为材料,研究了不同氮效率品种的农艺性状及生理特性的差异。结果表明,不同小麦品种间产量和氮素利用效率具有显著差异。基于氮肥吸收效率和氮肥农学效率将参试材料分为氮高效型、中效型和低效型。与氮中效型和低效型品种相比,氮高效型品种具有较高的产量、干物质和氮素积累量;在农艺性状上,氮高效型品种具有较高的粒重、收获指数(HI)、叶面积指数(LAI)和开花期旗叶面积;在生理上,氮高效型品种开花期旗叶的叶绿素含量、氮含量、净光合速率、硝酸还原酶活性和谷氨酰胺合成酶活性较高,而成熟期旗叶氮含量较低。聚类分析表明,淮麦30、徐麦32、矮抗58和扬麦16为氮高效型品种。经相关分析,小麦粒重、HI、LAI和开花期旗叶的面积、叶绿素含量、氮含量与氮效率呈显著正相关,小麦成熟期旗叶氮含量与氮效率呈显著负相关,这些指标可作为氮高效型小麦品种筛选的依据。

Agronomic and Physiological Characteristics of High Efficeint Nitrogen Utilization in Wheat

The morphological and physiological characteristics of 14 wheat varieties with different nitrogen efficiencies were studied by field experiment. The aim was to provide theoretical basis for the selection and regulation of nitrogen efficient varieties. The results show that wheat yield and nitrogen use efficiency have significant differences among different genotypes. Based on nitrogen agronomic efficiency and nitrogen recovery efficiency, the materials tested are divided into high, medium and low nitrogen efficiency types. Compared with the medium and low nitrogen efficiency cultivars, high nitrogen efficiency varieties have higher yield, dry matter and nitrogen accumulation. For agronomic traits, wheat varieties with high nitrogen efficiency have higher grain weight, harvest index (HI), flag leaf area and leaf area index (LAI). For physiology, wheat varieties with high nitrogen efficiency have higher flag leaf net photosynthetic rate, NR and GS activity in flag leaf at anthesis, chlorophyll content (SPAD), nitrogen content in flag leaf at anthesis and lower nitrogen content in flag leaf at maturity. Cluster analysis showed that Huaimai 30, Xumai 32, Aikang 58 and Yangmai 16 are varieties with high nitrogen efficiency. Correlation analysis showed that there is significantly positive correlation between leaf area, chlorophyll content, leaf area index, nitrogen content in flag leaf at anthesis, grain weight, harvest index and nitrogen efficiency, and there is significantly negative correlation between nitrogen content in flag leaf at maturity and nitrogen efficiency. These indicators can be used as basis to screen wheat with high nitrogen efficiency.