有棱丝瓜早熟相关性状主基因+多基因遗传模型分析

Mixed major genes+polygene genetic model analysis for early-maturity related traits in Luffa acutangula

【目的】通过主基因+多基因遗传模型分析有棱丝瓜早熟性相关性状的遗传规律,为早熟丝瓜品种选育提供理论参考。【方法】以高代自交系有棱丝瓜LC034(♀)和LC052(♂)为亲本构建6世代群体,采用主基因+多基因遗传分离法分析有棱丝瓜的4个早熟相关性状(第一雌花节位、始花期、第一坐果节位和始收期)遗传规律。【结果】LC034的4个早熟相关性状均极显著低于LC052(P<0.01)。F_(1)、BC_(1)P_(1)、BC_(1)P_(2)和F_(2)代群体的4个早熟相关性状变异系数为8.70%~25.46%、14.77%~37.67%、19.93%~38.97%和22.37%~46.81%,且4个早熟相关性状在F_(2)代群体的分离频率分布均包含多种正态分布的混合分布。MX2-ADI-ADI为第一雌花节位和第一坐果节位的最优遗传模型,受2对加性—显性—上位性主基因+加性—显性—上位性多基因控制;第一雌花节位在BC_(1)P_(1)、BC_(1)P_(2)和F_(2)代群体的主基因遗传率(h^(2)_(mg))分别为4.63%、84.69%和79.99%,多基因遗传率(h^(2)_(pg))为74.60%、0和0;第一坐果节位在BC_(1)P_(1)、BC_(1)P_(2)和F_(2)代群体的h^(2)_(mg)分别为2.38%、82.86%和76.45%,h^(2)_(pg)为57.04%、0和0。2MG-ADI为始花期的最优遗传模型,受2对加性—显性—上位性主基因控制,在BC_(1)P_(1)、BC_(1)P_(2)和F_(2)代群体的h^(2)_(mg)分别为72.02%、79.05%和86.53%。2MG-AD为有棱丝瓜始收期最优遗传模型,属于2对主基因控制的加性—显性遗传模型,在BC_(1)P_(1)、BC_(1)P_(2)和F_(2)代群体的h^(2)_(mg)分别为62.33%、84.79%和85.07%。【结论】有棱丝瓜的第一雌花节位、始花期、第一坐果节位和始收期均表现为数量性状的特点,受多基因的控制,其中第一雌花节位和第一坐果节位受2对主加性—显性—上位性主基因+加性—显性—上位性多基因控制,始花期受2对加性—显性—上位性主基因控制,始收期受2对加性—显性主基因控制。

【Objective】The purpose of the study was to provide theoretical reference for the breeding of early maturing Luffa acutangula varieties through the analysis of major genes+polygene genetic model for early-maturity related traits.【Method】A six-generation genetic population was constructed using the high-generation inbred lines LC034(♀)and LC052()of L.acutangula as parents,four early-maturity related traits of L.acutangula(the first female flower node,the first blooming date,the first fruit setting node and the first harvest date)were carried out by using major genes+polygene inheritance segregation analysis.【Result】The four early-maturity related traits of LC034 were extremely significantly lower than those of LC052(P<0.01).The coefficients of variation for the four early-maturity related traits in the F_(1),BC_(1)P_(1),BC_(1)P_(2),and F_(2) populations were 8.70%-25.46%,14.77%-37.67%,19.93%-38.97%,and 22.37%-46.81%.More‐over,the separation frequency distribution of the four early-maturity related traits in the F_(2) population contained the mixed distribution of multiple normal distributions.The optimal genetic model of the first female flower node and the first fruit setting node was the MX2-ADI-ADI model,which was controlled by 2 pairs of additive-dominant-epistatic major genes+additive-dominant-epistatic polygenes.The major gene heritability(h^(2) mg)of the first female flower node in BC_(1)P_(1),BC_(1)P_(2),and F_(2) generations was 4.63%,84.69%and 79.99%,respectively,while the polygenic heritability(h^(2) pg)was 74.60%,0 and 0.The h^(2) mg of the first fruit setting node in BC_(1)P_(1),BC_(1)P_(2),and F_(2) generations was 2.38%,82.86%and 76.45%,respectively,while the h^(2) pg was 57.04%,0 and 0.The optimal genetic model of the first blooming date was 2MGADI,which was controlled by 2 pairs of additive-dominant-epistatic major genes.The h^(2) mg of BC_(1)P_(1),BC_(1)P_(2),and F_(2) genera‐tions was 72.02%,79.05%,86.53%respectively.The optimal genetic model of the first harvest date was 2MG-AD,which was controlled by 2 pairs of additive-dominant major genes.The h^(2) mg of the first harvest date in BC_(1)P_(1),BC_(1)P_(2),and F_(2) gen‐erations was 62.33%,84.79%and 85.07%respectively.【Conclusion】The the first female flower node,the first blooming date,the first fruit setting node and the first harvest date of L.acutangula are all characterized by quantitative traits and are controlled by polygenes,among which the first female flower node and the first fruit setting node are controlled by 2 pairs of additive-dominant-epistatic major genes+additive-dominant-epistatic polygenes,the first blooming date is controlled by 2 pairs of additive-dominant-epistatic major genes,the first harvest date is controlled by 2 pairs of additive-dominant ma‐jor genes.