甘薯配合力分析的若干问题

首次将不完全双列杂交(NCⅡ)模式,结合甘薯遗传特点应用于甘薯育种。根据4年试验结果,提出了可行的试验方法、群体规模和评定指标;并就高淀粉、高产育种亲本选配中的若干问题提出了看法。

SOME PROBLEMS OF COMBINING ABILITY IN SWEET POTATO

The following conclusions are results from the data of 4 years experiments.1.Parents and crosses could be evaluated with the following 4parameters:1) general combining ability(GCA),2) variance of specific combining abiiity(SCA),3) means of crosses,and 4)coefficientof variation.2.Reliable results could be obtained when combining ability wascalculated with the means of crosses,one plant is planted per line whenthe number of lines of each cross exceeds 50,but 2 plants or more areneeded when it is about 30.3.Progenies with high yielding potential and high starch contentcould be obtained when crosses were made with parents with high GCAin dry matter weight and dry matter rate.4.The GCA of parents are comparatively stable,not changingwith environment changes,but the SCA of some crosses are quite variable under different environmental conditions.5.When high fresh weight cultivars are used for parents,it wouldnot be great possibility to obtain a high fresh weight progeny.