C型不育细胞质对玉米单交种及再杂交当代优势的效应研究

Studies on the C Type Sterile Cytoplasm Effects on Single Hybrid and Heterosis of the Two Single Hybrid Crossed Seeds in Maize

通过混合不同遗传标记花粉授粉法 ,研究 C型细胞质对玉米单交种和再杂交当代优势的效应。试验结果表明 ,不育种与同型正常种姊妹交籽粒间比较 ,C型胞质效应为 3.37% ;与同一有色父本杂交籽粒间比较 ,C型胞质效应为 2 .4 4 %。 2年 C型胞质效应平均分别为 2 .88%和 2 .94 %。同一 C型胞质对不同杂交种的效应不同 ,不同年份间有变化。不育种及正常种与同一有色单交种再杂交当代粒重均有杂交优势 ,杂交优势因不同父本而不同。正常种为母本 ,杂交优势为 3.73% ,不育种为母本 ,杂交优势为 2 .84 %

Several normal single hybrids and their corresponding isogenic C type cytoplasmic male sterile (CMS C) counterparts were used as females, pollinated by mixing marker of pollens to study C type cytoplasmic effect on single hybrid and heterosis of the two single hybrid crossed seeds in Maize. The results of comparing sister crossed kernel between CMS C hybrids and their counterparts, and comparing cross fertilized kernel with marker male parents, suggested that the C type cytoplasmic effect on kernel weight was different. The CMS C effect on kernel weight was 3.37% when comparing sister crossed kernel, and was 2.44% when comparing cross fertilized kernel with marker male parents. The average CMS C genetic effect was 2.88% and 2.94% respectively in two years. The same CMS C genetic effect varied with different hybrids and years. It was found that there was heterosis of cross fertilized kernel weight when the CMS C hybrids and their counterparts crossed with the same single hybrid, and the heterosis varied with different marker male parent. The cross fertilized kernel weight was 3.73% and 2.84% higher than that of normal hybrids selfed and CMS C hybrid sister crossed with their counterparts respectively.