【摘要】 水稻品种间杂种一代的优势是普遍存在的。不同性状间的优势差异较大,单株粒重的平均优势最强,次为单株秆重、谷秆比。单株粒重的增加主要依赖于每穗实粒数的提高,与双亲平均值关系极微。杂种一代的株高、全生育期、单株最高茎数、单株有效茎数、每穗总粒数、每穗实粒数、千粒重均与双亲平均值呈极显著的正相关。更多还原

【Abstract】 Heterosis,while common in F₁ inter—varietal rice hybrids,variedconsiderably with different characteristics.Among the 13 characteristicsstudied the average heterosis was highest in grain weight per plantfollowed by straw weight per plant and decreased in the followingorder:grain to straw ratio,maximum number of tillers per plant,filled grains per panicle,effective tillers per plant,total grains perpanicle,percentage of filled grains,one thousand grain weight andplant height.For the total growth duration,numder of days toheading and the ratio of effective tillers,F₁ hybrids manifestedslightly lower than the mid—parent.The plant height,total growthduration,maximum number of tillers per plant,effective tillers perplant,total grains per panicle,filled grains per plant and onethousand grain weight of F₁ hybrids were positively correlatedto those of the mid—parent very significantly.The increase of grainweight per plant depended on that of the filled grains per panicleand had little to do with the mid—parent更多还原