矮秆玉米自交系“82-3”穗部性状的遗传及利用评价

Inheritance of ear traits of dwarf maize inbreed "82-3" and its evaluation

以矮秆资源82-3自交系为父本与高秆自交系W1杂交,通过对双亲、F1和F2等不同群体穗部性状调查,分析82-3穗部性状在不同世代的遗传.结果表明,矮秆自交系82-3除穗轴较粗外,穗部其他各性状表现稳定,且优于亲本W1,F1超亲优势明显,尤其穗重和穗粒重,超亲优势率分别达46.98%和59.51%,F2表现正态分布且超亲分离严重,为选择和改良奠定了基础;穗部各性状遗传力不同,轴粗的遗传力相对最高,达84.11%,其次为穗粗,达67.39%,而穗长的遗传力相对最低,仅为31.39%.相关分析表明,株高与单株产量相关显著,而穗位高与单株产量关系不大.因此,在资源改良或杂交种选育中,可以利用82-3的矮秆、大穗等优势,通过降低穗位以间接提高选系材料或杂交种抗倒伏风险的能力.

The investigation had been made on ear traits of parents, F1 and F2 generations composed by dwarf resource inbreed line ＂82- 3＂ crossed with high inbreed line W1. The results showed that the dwarf inbreed ＂82 -3＂ showed stability and outstanding ear traits except for axis diameter compared with the parent line W1, and F1 significantly performed heterosis over parents especially for ear weight and grain yield per ear with the ratio of 46.98% and 59.51%, respectively. Normal distributions were formed on ear traits in F2 population with great over parents segregations, which established the basis for selection and modification of corn materials. The heritability in broad sense （ Hs2 ） varied with ear traits and that of axis diameter which was the highest（84.11% ） followed by ear diameter（67.39% ）, and the ear length the lowest（31.39% ）. Correlation analysis showed that the plant height, instead of ear height, had significant relationship with the grain yield per ear. It can be inferred that it＇ s possible to enhance indirectly the ability of lodging resistance of material or hybrid by inducing the ear height usingthe advantages of low plant height and big ear of ＂82 - 3＂ inbreed line during the process of resourcematerial modification and hybrid selection.