再生稻的产量形成及其高产群体分析

Analysis on Yield Formation and Its Higher-yielding Population Quality of Ratooning Rice

以云南省8个大面积应用的再生稻品种为材料,研究再生稻的产量形成,并通过改变施氮量和施氮时期,分析再生稻最高产品种的高产群体质量。结果表明：再生稻抽穗期到成熟期的生长率为头季稻抽穗到成熟期的37.87%,再生稻的产量为头季稻的36.95%,再生稻产量与头季抽穗后到成熟期的群体生长率和再生稻抽穗期LAI呈显著的正相关,提高再生稻产量的关键是提高其有效穗,而提高再生稻有效穗的关键是提高腋芽萌发率和存活率;施氮量和施氮时期创造了再生稻不同质量群体,高产质量群体齐穗期LAI为3.6以上,抽穗期到成熟期的群体生长速率在8.5 g/（m2·d）以上,对应的氮肥用量195 kg/hm2,在头季稻齐穗后15 d和收获2~3 d均施。

Taking 8 ratooning rice varieties already widely cultivated as the materials,a study on the yield formation of ratooning rice was carried out,and taking the screened ratooning rice varieties of the highest yield as the materials, by changing the amount of nitrogen fertilizer and fertilizing dates, the population quality of higher-yielding ratooning rice was studied.The results showed that：the crop growth rate of the ratooning rice from heading to maturity was 37.87%of that of the first crop,the yield of the ratooning rice was 36.95%of that of the first crop ;the key to improve the yield of the ratooning rice was to increase the effective panicles,the key to improve the panicles of the ratooning rice was the improvement of sprouting and alive buds of the ratooning rice.There was significantly positive correlation coefficient between leaf area index of the first cropping rice in the maturity stage,the crop growth rate from the heading stage of the first cropping rice to the maturity stage of the ratooning rice and the yield of the ratooning rice.Changing the amount of nitrogen fertilizer and the fertilizing dates created differences in population quality of the ratooning rice.The population quality of the higher-yield-ing ratooning rice was above LAI 3.6 in the heading stage,the crop growth rate above 8.5 g/（ m2？ d） from heading to maturity,that is,the total amount of nitrogen fertilizer was 195 kg/hm2applied 15 days after full heading of the first cropping rice and 2 to 3 days after the harvest of the first cropping.