一种两收模式下多年生稻产量潜力初探

Preliminary Study on Yield Potential of Perennial Rice Under Two-Harvest Model

以多年生稻品系PR25和再生稻品种渝粳优5029(RR1)、甬优1540(RR2)、佳辐占(RR3)、宜优673(RR4)、内优7075(RR5)为材料,采用单因素试验探讨多年生稻与再生稻产量、产量构成、生育期、SPAD、根系活力等性状的异同。结果表明:PR25产量与再生稻相比,头季持平或者略低,第二季PR25产量为471.10 kg/667m^2,显著高于所有再生稻品种,较RR1、RR2、RR3、RR4和RR5分别增产48.22%、34.79%、60.95%、31.71%、45.58%;周年产量PR25为1031.63 kg/667m^2,亦显著大于再生稻品种,较RR1、RR2、RR3、RR4和RR5分别增产5.82%、10.41%、47.00%、13.19%和42.66%。多年生稻PR25再生季的周年产量较再生稻高的主要原因是:多年生稻再生季的单位面积颖花数、有效穗数和结实率均高于再生稻的再生季;PR25头季齐穗后剑叶SPAD衰减幅度较小,剑叶具有较强的光合能力,头季成熟期根系维持在较高活力水平且再生能力较强;多年生稻再生季营养生长期至营养生长与生殖生长并进期明显长于再生稻,进而全生育期较再生稻呈延长趋势,利于干物质积累。

A single factor experiment was conducted to investigate the differences of yield,yield components,growth period,SPAD and root activity between the perennial rice line PR25 and the ratooning rice varieties Yujingyou 5029(RR1),Yongyou 1540(RR2),Jiafuzhan(RR3),Yiyou 673(RR4)and Neiyou 7075(RR5).The results showed that:(1)the yield of PR 25 in the first season was approximate to or slightly lower than those of the ratooning rice varieties;in the second season,PR25 yielded 7066.5 kg/hm^2,which was 48.22%,34.79%,60.95%,31.71%and 45.58%higher than RR1,RR2,RR3,RR4 and RR5,respectively,reaching the significant levels;the annual yield of PR25 was 15474.45 kg/hm^2,5.82%,10.41%,47.00%,13.19%and 42.66%higher than that of RR1 RR2,RR3,RR4 and RR5,respectively,reaching significant increases;(2)the main reason why the annual yield of PR25 in ratooning season was higher than that of ratooning rice was that the number of spikelets per unit area,effective panicles and seed setting rate of PR25 were higher than those of ratooning rice;after full heading,the flag leaf of PR25 had a strong photosynthetic capacity with a slight decrease of SPAD value;at the maturity period of the first season,PR25 maintained a high root activity and a strong regeneration ability;the period from vegetative growth to vegetativereproductive growth of perennial rice was significantly longer than that of ratooning rice,furthermore,the whole growth period of perennial rice was longer than that of ratooning rice,which was beneficial to dry matter accumulation.