杂交中稻氮肥农学利用率与植株地上部农艺性状关系研究

Relationship between Nitrogen Agronomic Efficiency and Aboveground Agronomic Characteristics in Mid-season Hybrid Rice

以16个杂交中稻组合为材料,在正常施氮和不施氮2个施氮水平下研究了杂交中稻氮肥农学利用率与植株地上部农艺性状的关系。结果表明,杂交中稻的氮肥农学利用率存在较大的基因型差异,组合间氮肥农学利用率与施氮处理籽粒产量呈极显著正相关。在高产正常施氮水平条件下,杂交中稻氮肥高效利用率组合要求最高苗数(x1)多,株高(x6)较高,倒3叶(x13)较窄,生物产量(x18)和结实率(x21)较高,上述性状与氮肥农学利用率(y)间存在极显著线性关系,回归方程为y=-75.8901+0.335 9x1+0.449 2x6-15.859 5x13+0.199 9x18+0.345 4x21,决定系数为89.53%。因此,这些性状可作为杂交后代及组合鉴定时田间选择的参考指标。

The relationship between nitrogen agronomic efficiency and agronomic characteristics was investigated using 16 mid-season hybrid rice combinations on two levels of nitrogen application. The results showed that there were significant genotypic differences in nitrogen agronomic efficiency, highly significant positive correlations were observed between nitrogen agronomic efficiency and grain yield in the treatment of applying nitrogen. In normal ni- trogen-applied conditions for a high grain yield, the agronomic characters of mid-season hybrid rice combinations with a higher nitrogen agronomic efficiency were a greater number of maximum tillers （x1）, higher plant height （x6 ）, biological yield （x18） and seed setting percentage （x21） but narrower width of 3 rd leaf from top （x13）. There was a highly significant linear correlation between nitrogen agronomic efficiency （y）and these characters with the regression equation as, y=-75.8901＋0.3359x1＋0.4492x6-15.8595x13,＋0.1999x18＋0.3454x21. R2=0.8953.Therefore, these characters can be used as an reference index to select mid-season rice hybrids for a higher nitrogen agronomic efficiency.