生育进程相近的谷子杂交种两系亲本的选育及其杂种优势分析

利用“两系”进行谷子杂种优势制杂交种时，不育系抽穗期和开花期常较恢复系早，二者只有错期播种才可在花期相遇并杂交结实。通过改良现有不育系与抗除草剂恢复系抽穗期和开花期，选育出符合谷子“两系”改良育种目标的优良高度雄性不育系3个（Y1A、Y2A和Y3A）及抗除草剂拿捕净恢复系5个（K17-1、K18-49、K18-54、K18-62和K18-70），按NCII不完全双列杂交组配15个组合，分析亲本和杂交组合配合力、超亲优势及超标优势，预测其杂种优势。结果显示，亲本的配合力各不相同，有不同优良农艺性状选择方面利用价值；杂交组合间各性状超亲优势和超标优势表现存在差异，但杂种优势无关联、无规律性，分析预测亲本存在杂种优势。同时，“两系”亲本各自性状表现优良，选出的杂交组合Y3A×K18-49具有强杂种优势，可作为苗头杂交种继续进行杂种优势育种。本研究结果为谷子杂交种制种提供了可同期播种的“两系”亲本及苗头优良杂交种，简化了谷子杂交制种环节。

Breeding and Heterosis Analysis of Two Line Parents of Foxtail Millet Hybrids with Similar Growth Process

When using “two lines” to make hybrids with foxtail millet heterosis, the heading and flowering stages of sterile lines are often earlier than those of restorer lines, and they can meet and cross at flowering stage only in different sowing periods. In this study, the heading and flowering periods of existing sterile lines and herbicide-resistant restorers were improved, three high-quality male sterile lines (Y1A, Y2A and Y3A) and five herbicide resistant Napujing restorers (K17-1, K18-49, K18-54, K18-62 and K18-70) were selected and bred in line with the improved breeding goal of “two lines” of millet. The 15 combinations were made by NCII incomplete diallel crossing with three sterile lines and five restorer lines. Combining ability, transgressive heterosis and superstandard heterosis of parents and cross combinations were analyzed, and their heterosis were predicted. It was concluded that the combining ability of parents were different and had different utilization value in the selection of excellent agronomic characteristics. There were differences in transgressive heterosis and superstandard heterosis among hybrid combinations, but the heterosis was unrelated and irregular. It was predicted that parents have heterosis. The parents of the “two lines” performed well in their respective characteristics, the hybrid combination Y3A×K18-49 had strong heterosis and heterosis breeding could be continued in the coming year. The results provide available parents and good hybrids for simultaneous sowing and hybridization of foxtail millet “two lines” and simplify the process of foxtail millet hybrid seed production.