Abstract:
Embryo is a key determinant of kernel-oil in maize. Higher calorific value of maize kernel is attributed to increment in kernel-oil and it stores in specialised structure called embryo. Understanding the genetic behaviour of embryo size and weight related-traits is inevitable task for genetic improvement of kernel-oil. Here, the six-basic generations (P1, P2, F1, F2, BC1P1 and BC1P2) of three crosses (CRPBIO-962 × EC932601, CRPBIO-973 × CRPBIO-966 and CRPBIO-966 × CRPBIO-979) between contrasting embryo-sized maize inbreds were field evaluated at three locations to decipher the genetics of twenty embryo, kernel and embryo-to-kernel related-traits through generation-mean-analysis (GMA). Combined ANOVA revealed the significance of all the traits among generations; however, location and generation × location were found to be non-significant (P > 0.05) for most of the traits. Significance (P < 0.05) of scaling and joint-scaling tests revealed the presence of non-allelic interactions. Elucidation of six-parameters disclosed the predominance of dominance main-effect (h) and dominance × dominance interaction-effect (l) for most of traits. The signs of (h) and (l) indicated the prevalence of duplicate-epistasis type across crosses and locations. Thus, the population improvement approaches along with heterosis breeding method could be effective for improvement of these traits. Quantitative inheritance pattern was observed for all the traits with high broad-sense heritability and better-stability across locations. The study also predicted one to three major-gene blocks/QTLs for embryo-traits and up to 11 major-gene blocks/QTLs for embryo-to-kernel traits. These findings could provide deep insights to strategize extensive breeding methods to improve embryo traits for enhancing kernel-oil in sustainable manner.
摘要:
胚是玉米籽粒油的关键决定因素。玉米籽粒的较高热值归因于籽粒油的增加,并以称为胚的专门结构存储。了解胚胎大小和体重相关性状的遗传行为是核仁油遗传改良的必然任务。这里,三个杂交(CRPBIO-962×EC932601,CRPBIO-973×CRPBIO-966和CRPBIO-966×CRPBIO-979)的六个基本世代(P1,P2,F1,F2,BC1P1和BC1P2)在三个位置进行了实地评估,以破译二十个胚胎的遗传学。通过世代均值分析(GMA)的内核和胚胎到内核相关性状。组合方差分析揭示了各代之间所有性状的重要性;然而,发现大多数性状的位置和世代×位置均不显着(P>0.05)。缩放和联合缩放试验的显著性(P<0.05)显示存在非等位基因相互作用。六个参数的阐明揭示了大多数性状的优势主要效应(h)和优势×优势相互作用效应(l)的优势。(h)和(l)的迹象表明跨十字架和位置的重复上位型患病率。因此,种群改良方法和杂种优势育种方法可以有效地改善这些性状。对于所有具有高广义遗传力和跨位置更好稳定性的性状,都观察到了定量遗传模式。该研究还预测了胚胎性状的一到三个主要基因块/QTL,胚胎到内核性状的多达11个主要基因块/QTL。这些发现可以提供深刻的见解,以制定广泛的育种方法来改善胚胎性状,从而以可持续的方式增强果仁油。