两系杂交籼稻配合力分析

Analysis on Combining Ability of Two-Line indica Hybrid Rice

以5个新育成的籼型水稻光温敏核不育系和生产上广泛应用的不育系培矮64S为母本,6个新育成的恢复系为父本,采用NCⅡ设计配制36个组合,分别在海南和湖北进行试验(完全随机区组设计,3次重复),考查单株产量等10个主要农艺性状,分析配合力。大多数性状的一般配合力和特殊配合力方差达到显著或极显著水平,各性状的一般配合力方差均大于特殊配合力方差,表明基因的加性作用大于非加性作用。5个新育成的不育系产量的一般配合力效应没有显著差异,但都显著高于对照不育系培矮64S;华885S的产量一般配合力效应最高,特殊配合力方差较大,是参试不育系中产量配合力最好的亲本;华893S的每穗总粒数和每穗实粒数的一般配合力效应最高,特殊配合力方差最大,是提高每穗粒数的优良亲本;播始历期以华328S表现最好,以华328S作母本可以选育到生育期变化较大的组合,既可以培育中籼型组合,也可以培育晚籼型组合;株高一般配合力以华884S的负效应最高,特殊配合力方差显著大于组合平均值,表明用华884S作母本,容易选育出植株较矮、抗倒性较强的组合。恢复系中,华恢2185的产量一般配合力效应表现最高,特殊配合力方差最大,千粒重、穗长、结实率和播始历期的一般配合力效应均排在参试恢复系首位,是一个理想的亲本;株高、每穗总粒数和着粒密度的配合力,以华1108表现最好。特殊配合力效应最大的前10个组合和单株产量最高的前10个组合顺序完全对应,表明在水稻杂种优势利用中,亲本之一有良好的一般配合力效应,另一个亲本或双方都具有良好的特殊配合力,就有可能育成强优势组合。

Five newly developed photo- and thermo-sensitive genic male sterile lines, Hua 884S, Hua 885S, Hua 886S, Hua 893S and Hua 328S and the control Pei＇ai 64S which has been widely utilized in rice production were used as female parents, and six newly developed restorer lines, Huahui 2185, Huahui 1035, Hua 1108, BR06, Hua 190 and Huahui 3 were used as male parents. Thirty-six crosses were made according to NC Ⅱ mating design. The plots of F1 s were arranged in the field in a randomized complete block design with three replications in Hainan Province in spring and Hubei Province in summer in 2006, respectively. Grain yield per plant and other nine traits were investigated, and combining ability was analyzed. Both general combining ability （GCA） and specific combining ability （SCA） were significant at 5 % or 1% levels for most traits, and the additive effects were more important than non-additive effects. GCA of yield in five newly developed sterile lines was similar, but significantly higher than that in Peirai 64S. Hua 885S was the best female parent with the highest GCA and SCA in yield, and Hua 893S was the best sterile line with the highest GCA and SCA in increasing number of grains and number of filled grains per panicle. Hua 328S with the highest negative GCA effect and bigger SCA of growth duration could be used for developing medium and late indica hybrid rice. Hua 884S with the highest negative GCA and bigger SCA of plant height could be used for developing lodging-resistant and dwarf hybrid rice. Huahui 2185, which had the highest GCA and SCA of yield, higher GCA of 1000-grain weight, panicle length, seed setting rate and growth duration, was an ideal male parent. Hua 1108 was better for GCA and SCA of plant height, number of grains per panicle and grain density on panicle. Moreover, the top ten combinations with the biggest SCA effect were also the top ten combinations with the highest yield, implying that the combinations with strong heterosis would be made between one parent with higher GCA and another parent with bigger SCA or both parents with bigger SCA.