糜子矮秆突变体“819”矮秆基因的遗传学分析

为揭示糜子矮秆突变体“819”矮秆基因的遗传规律,为后续定位矮秆突变基因提供理论基础,研究调查了糜子矮秆突变体“819”与高秆材料J12,以及它们杂交产生的674个F₂代个体的株高、穗长、穗颈长、分蘖数、茎节数、二级枝梗长度1、二级枝梗长度2、二级枝梗长度3、二级枝梗间距1、二级枝梗间距2共10个性状,进一步利用方差分析、卡方检验、相关及回归分析、主成分分析对这些性状进行研究。结果表明,糜子矮秆突变体“819”的矮秆性状是由单基因控制的隐性性状;株高与穗长、穗颈长、分蘖数、茎节数、二级枝梗长度1、二级枝梗长度2、二级枝梗长度3、二级枝梗间距1呈极显著正相关(P<0.01),与二级枝梗间距2呈显著正相关(P<0.05);株高(Y)对其他农艺性状的回归方程为:Y=-18.446+1.491X₁+1.222X₂+6.827X₄+1.319X₇+0.746X₈,回归方程的拟合度为0.811,回归方程经显著性检验达到极显著水平(P<0.01),可以利用回归方程对株高进行预测;糜子F₂群体的10个性状进行主成分分析获得3个主成分,这3个主成分的累积贡献率高达72.656%,3个主成分分别被命名为长度因子、茎节数因子、枝梗间距因子。研究结果为矮秆基因定位、矮秆后代的评价选择提供了依据。

Genetic analysis of dwarf gene for dwarf mutant“819” in Panicum miliaceum L.

In order to uncover the genetic characteristics of dwarf gene from a dwarf mutant “819”, and provide theoretical basis for the subsequent locating of dwarf mutant gene ten traits' including plant height, ear length, neck length, tiller number, stem node number, length of second panicle branch 1, length of second panicle branch 2, length of second panicle branch 3 and so on were investigated for Panicum miliaceum L. crossing parents dwarf mutant “819”, high-stem material J12 and their 674 F₂ individuals, and further variance analysis, cartesian inspection, correlation and regression analysis, principal component analysis were performed for these traits. The results showed that dwarf trait of dwarf mutant “819” was a recessive trait controlled by a single gene. A significantly positive correlation was found between plant height and ear length, tiller number, stem node number, secondary branch length 1, secondary branch length 2, secondary branch length 3, secondary branch distance 1 (P<0.01), and a significant positive correlation was found between plant height and secondary branch spacing 2 (P<0.05). The regression equation of plant height (Y) and other agronomic traits was as follow: Y=-18.446+1.491X₁+1.222X₂+6.827X₄+1.319X₇+0.746X₈, and the fitting degree of which was 0.811. The regression equation reached significant level (P<0.01) and could be used to predict the plant height. Three principal components were obtained by principal component analysis for 10 characters of F₂ population, which accounted for 72.656% of the cumulative contribution rate. These three principal components were named as length factor, stem node number factor and branch spacing factor respectively. The results above provided basis for locating dwarf gene and evaluating, selecting of dwarf offsprings.