杂交稻强再生力鉴定指标的建立及组合筛选

Indexing and Recommended Combinations of Rice Varieties for New Breeds with Strong Ratooning Ability

【目的】解析生产上杂交稻品种的再生力鉴定指标,以期筛选出头季稻产量高、再生力强的组合,为再生稻新组合的选育和研究提供基础。【方法】试验于2015-2017年在福建省三明市尤溪县,以23个杂交稻组合为材料,其中3个为再生稻发展不同阶段的代表性品种,统一采用高产栽培方式,利用相关、回归与通径分析,研究性状指标与再生稻产量及构成因素的关系,进而确定再生力筛选指标,并进行新组合再生力的比较和筛选。【结果】头季稻产量与穗粒数的相关系数为0.83,达极显著水平,穗粒数对产量的贡献率达54.61%,因而头季高产的品种特征为重穗,以穗粒数的优势形成巨大的库容量;再生季产量与有效穗数的相关系数为0.70,达显著水平,有效穗数对产量的贡献率达38.98%,显示再生季的库容量来源于多穗。头季稻的有效穗数、有效穗数与母茎数比率,均与再生稻产量极显著相关,系数分别为-0.86和0.82,经回归分析获得再生稻产量预测模型,其预测准确率分别为70.6%~99.6%和76.5%~99.5%。【结论】再生季产量是衡量再生力强弱的直接依据,而头季有效穗数、有效穗数与母茎数比率是强再生力品种的重要筛选指标。经鉴定和筛选,内6优7206、川优7185、川优7206、荃优7028为再生稻优良组合。

【Objective】To establish an indexing system on rice ratooning ability for studies and breeding of hybrids.【Methods】Twenty-three varieties including 3 representing different developing ages were cultivated under same conditions in Youxi county,Sanming,Fujian from 2015 to 2017.Correlation,regression and path analyses were conducted on the traits,yield and yield factors on the cultivars.【Results】The 1 st-season rice yield of the cultivars significantly correlated with the grain number per panicle(r=0.83)with a 54.61% contribution to the yield indicating a critical role of heavy panicles to high yield.In ratooning season,the yield significantly related to the effective panicle number(r=0.70)with a 38.98% contribution rate suggesting a shift of storage capacity in the plants between the two seasons.The effective panicle count and the effective panicle/stem number ratio of the rice plants in the 1 st season significantly correlated with the yield in the following season at r=-0.86 and 0.82,respectively.A prediction model derived from the regression analysis base on the panicle count for the ratooning rice yield was 70.6%-99.6% accurate and,based on the effective panicle/stem number ratio,76.5%-99.5%.【Conclusions】As a measure of the ratooning ability of a rice variety,the panicle count and/or the effective panicle/stem number ratio of the plants could be used to appropriately estimate the yield.Accordingly,Nei-6-you 7206,Chuan-you 7185,Chuan-you 7206,and Quan-you 7028 were identified as superior varieties for breeding hybrids with a strong ratooning ability.