幼穗分化期至齐穗期水分胁迫对水稻产量及功能叶性状的影响

2013年在宜良县通过田间试验,研究了水稻幼穗分化期至齐穗期水分胁迫对云南大面积生产应用的6个粳稻品种产量及产量构成因素、功能叶叶面积及SPAD值的影响。结果表明:幼穗分化至齐穗期水分胁迫后6个品种实际产量比正常灌溉产量下降11.03%,达极显著水平。幼穗分化至齐穗期水分胁迫后有效穗数、总粒数、实粒数分别比正常灌水降低4.58%、7.21%、8.53%,其中对实粒数影响最大,达显著水平。水分胁迫后齐穗期功能叶高效、低效、总叶面积指数比正常灌水分别降低13.60%、10.55%、12.92%,水分胁迫后幼穗分化至齐穗期的倒1叶、倒2叶、倒3叶SPAD值比正常灌水分别降低1.26%、1.32%、2.69%。在幼穗分化至齐穗期水分胁迫条件下,抗旱性强的品种穗总粒数、实粒数、结实率降低的幅度小,抗旱性较弱的品种降低的幅度大;抗旱性强的品种功能叶SPAD受影响越小,且有增加的趋势,而抗旱性较弱的品种呈下降趋势。

Effects of water stress on rice grain yield and functional leaf traits during panicle differentiation to full heading stages

Field experiments were conducted in 2013 in Yiliang to study the effects of water stress on grain yield, yield component, functional leaf area and SPAD value during panicle differentiation to full heading stages. The results showed that compared with normal irrigation mode, grain yield was decreased by 11.03% under water stress during panicle differentiation to full heading stages, reaching a significantly different level. Effective panicles, total grains per panicle and filled grains per panicle were decreased by 4.58%, 7.21%, 8.53%, respectively, which was found to be significant on filled grains per panicle. Effective leaf area index, low efficient leaf area index and total leaf area index at full heading stage became decreased by 13.60%, 10.55%, 12.92%, respectively. SPAD value of the first, second and third leaves from the top were decreased by 1.26%, 1.32%, 2.69%, respectively. Under water stress during panicle differentiation to full heading stages, the descendent rates of total grains per panicle, filled grains per panicle and fertility rate were low in the highly drought resistant varieties, whereas high in the poorly drought resistant varieties. Functional leaf SPAD value of the highly drought resistant varieties had been barely affected, showing an increasing tendency, but that of the poorly drought resistant varieties was decreased.