海岛棉F1产量性状的条件遗传分析

调查了海岛棉5×4不完全双列杂交实验的3年产量性状资料,运用包括加性、显性、加性×环境互作、显性×环境互作的遗传模型进行条件和非条件的遗传分析.双列杂交的亲本具有不同果枝类型.非条件遗传方差结果表明,总皮棉产量没有检测到显著的非条件加性效应方差.但是铃重、霜前铃数、霜后铃数以及霜前皮棉产量的条件分析结果发现这些性状的加性效应均对总皮棉产量的加性效应有贡献.因此,可通过这些性状改良总皮棉产量的加性效应表现.当某材料产量构成因素的加性贡献率比较高时,选择该材料作为杂交亲本可望获得具有较好总皮棉产量表现的后代.各产量构成因素的显性效应对霜前皮棉产量和总皮棉产量的杂种优势具有较大的贡献率.产量构成因素之间又相互影响.那些能够检测到显著的正向贡献率的性状将为进一步改良目标性状提供可能.本研究结果显示运用条件分析方法不仅能分析原因性状对目标性状的贡献率,还可以分析特定亲本(或组合)的某一性状对该亲本或组合目标性状的作用大小和正负,据此就可以指导某一亲本后代或组合的目标性状的间接选择.这对实际育种中具体组合的选择具有重要的意义.

Genetic Analysis for F1 Yield Traits with Conditional Approach in Island Cotton (Gossypium barbadense L.)

A genetic model with additive, dominance and genotype × environment interaction effect was employed to analyze the 3-year data of F1 hybrids from 5 × 4 diallel cross, whose parents were Island cotton and had different fruit branch types. Unconditional and conditional genetic variances were conducted for analyze genetic impacts of yield components on yield. Results of unconditional genetic variances showed that there were no additive variance of total lint yield. But conditional additive effects of total lint yield, when excluding the phenotype of boll weight, boll number at prefrost, boll number at postfrost, and lint yield at prefrost,indicated that improving the additive effects of the total lint yield was still possible. Crossing and selecting component traits with high contributive additive effects could obtain good offsprings. Yield components contributed large dominance effects to the heterosis of lint yield at prefrost and total lint yield in crosses. Yield component traits were controlled with each other. The traits having positive contributive effects could be applied to further improve target traits.