小麦籽粒产量选择指数的研究

本文用35个普通小麦品种(系)为试验材料,研究单株籽粒产量的遗传参数及选择指数。结果表明:单株籽粒产量的遗传力、遗传进度均较低,直接选择效果较差。通过各独立性状进行间接选择,效果亦不理想。将各性状分别与单株产量建立指数方程进行综合选择,则以穗粒数、剑叶面积、单株穗数为好,相对效率分别为112.47%、107.92%、103.20%。在所有三个以上性状所组成的选择指数方程中,凡包含了单株产量的构成因素:穗粒数、千粒重、单株穗数的指数方程,其遗传进度最大,相对效率最高。由穗粒数、千粒重、单株穗数、单株生物产量、剑叶面积所组成的选择指数方程:y=0.2127x_1+0.1932x_2+3.8454x-3-0.3406x_4+0.0598x_7,相对效率达173.13%,超过了大部分由6个以上性状所组成的选择指数方程的遗传进度。在育种工作中,对这些性状综合筛选,将事半功倍。

A STUDY ON THE GENETIC PARAMETER AND SELECTION INDEX OF THE INDIVIDUAL PLANT YIELD IN WHEAT

Geneticparameters and selectio index of th individual plant yield of 35 wheat varieties are analysed.The results indicate that direct selection is not satifactory because of the weak heritability and slow heredidary progression of individual plant yield and indirect selection ba- sed on Some independent characters is not ideal either.But the compre- hensive selection based on the indices equation oftheindividual plant yield to each character is effective.Among the characters the grain numbers per ear,the area of the swordleaf and ear numbers per plant are the best ones with relative selection efficiencies of 112.4%,107.9% and 103.2%. In the selection indicies equation with more than3 characters and the fa- Ctors of forming the individual plant yield,the hereditary progression is the fastest and the relative selection efficience is also the highest.Bes- ides,the bionomies of the individual plant and the area of sword leaf are also important characters.The selection indicies equation contained all these five characters are:y=0.2127x_1+0.1932x_2+0.3854x_3-0.3406x_4+ 0.0598x_7,the relative selection efficiency up to 173.3%.Therefore,com- prehensive selection to these5 characters can increase the selection ef- ficiency,shorten the breeding duration and breed out new wheat varieties.