杂交中稻氮素利用效率的简易评价指标研究

Study on Appraising Index of Fertilizer-Nitrogen Use Efficiency for Mid-Season Hybrid Rice

2008-2009年,以18个近年通过审定的杂交中稻组合为材料,在施氮与不施氮条件下,研究了氮素利用效率与齐穗后库源结构和物质分配的关系。结果表明,齐穗期叶粒比分别与氮素稻谷生产效率和氮收获指数呈极显著负相关,齐穗期到成熟期叶片SPAD值衰减指数、LAI衰减指数和稻谷收获指数分别与氮素稻谷生产效率和氮收获指数呈极显著正相关。经多元逐步回归分析,叶粒比、SPAD值衰减指数、LAI衰减指数和稻谷收获指数4个指标显著影响氮素稻谷生产效率和氮收获指数,决定系数分别为0.6822-0.8154、0.6836-0.8285,SPAD值衰减指数和稻谷收获指数可分别作为预测氮素稻谷生产效率和氮收获指数的简易指标。杂交中稻氮高效利用组合的植株指标参考值：叶粒比1.25-1.58 cm2/sp ikelet、SPAD值衰减指数0.48-0.49、LAI衰减指数0.50-0.57、稻谷收获指数0.63-0.64、有效穗185.10-230.03万/hm^2,杂交中稻品种的氮素利用率可划分为氮广适应型、高氮适应型、低氮适应型和氮利用率较差型4类。

In 2008 -2009, using 18 approved mid-season hybrid rice combinations as materials, the relation of the nitrogen use efficiency and the sink-source structure and matter distribution after full heading under nitrogen application and no nitrogen application was studied. The results showed that there were highly significant negative correlations between ratio of leaf to grain（RLG） at full heading and grain productive rate of nutrient （ GPRN ）, harvest index of nutrient （HIN） and highly significant positive correlations between decreased index of SPAD value （DISV）, decreased index of LAI （DIL）, harvest index of grain（HIG） and GPRN, HIN were observed. Multiple stepwise regression analysis showed that GPRN and HIN were significantly influenced by RLG, DISV, DIL and HIG, and the determination coefficient ranged from 0. 6822 to 0. 8154 and from 0. 6836 to 0. 8285. DISV and HIG could be used as an reference index of selecting mid-season hybrid variety for high fertilizer-nitrogen use efficiency. The variety for high fertilizer-nitrogen use efficiency would have the following plant characteristics ： RLG 1.25 - 1.58 cm^2 per spikelet, DISV 0.48 - 0.49, DIL 0.50 - 0.57, HIG 0. 634）. 64, productive panicles 185.10 × 10^4 - 230.03 × 10^4 per hm^2 , there were 4 combination types for nutrient use efficiency of mid-season hybrid rice were distinguished ： high adapt type in high and low nitrogen, high adapt type in high nitrogen, high adapt type in low nitrogen and poor adapt type in high and low nitrogen.