玉米雄穗性状的配合力及遗传参数研究

Study on Combining Ability and Hereditary Parameter of Tassel Characters in Maize

以7份具有不同雄穗性状的玉米自交系为材料,采用Griffing方法4的双列杂交,估算了玉米雄穗主轴长度、分枝数、平均分枝长度、小穗着生密度和每穗小穗数5个性状的一般配合力、特殊配合力和相应的遗传参数,并进行了性状间一般配合力相关分析。结果表明:5个雄穗性状一般配合力明显高于特殊配合力,基因累加效应占遗传主导地位;5个性状的h2B(%)分别为80 72,82 96,85 13,84 211,61 10;h2N(%)分别为60 92,66 11,44 62,67 20,38 96。性状间一般配合力效应相关分析发现,分枝数、小穗着生密度与每穗小穗数间分别呈极显著和显著正相关(r=0 9347 ,r=0 8345 )。选择雄穗时,对分枝数、小穗着生密度宜进行早代选择。

By using diallel crossing of Griffing method 4,7 maize inbred lines which were different in tassel characters,were evaluated for main axis length,branch number,mean length of branch,spikelet density,spikelet density per tassel as well as normal combining ability,special combing ability and corresponding genetic parameters of the five characters.And at the same time analysis was made on the correlation of the normal combing ability among the characters. The results showed the normal combining ability of the five characters were obviously higher than special combining ability and additive effect for the genes were dominant.h_B^2(%) for the five characters was 80.72,82.96,85.13,84.211 and 61.10 respectively and h_N^2 was 60.92,66.11,44.62 ,67.20 and 38.96 respectively.It was found by correlative analysis that branch number and spikelet density had highly significant positive correlation and significant positive correlation with normal combine ability of spikelet density per tassel respectively (r=0.934 7^(**),r=0.834 5~*).When selecting tassel,branch number and spikelet density should be considered in earlier generation.