Dilla College of Education, P. O. Box 334, Dilla, Ethiopia.
School of Plant and Horticultural Sciences, Hawassa University, Hawassa, Ethiopia.
Sci Rep. 2023 Nov 28;13(1):20981. doi: 10.1038/s41598-023-47869-0.
Selection based on yield alone may not be effective for yield improvement in plant breeding programs. Thus, in order to progress the genetic gains during selection, yield should be considered along with potential yield contributing traits. The objective of this study was to improve the genotype of amaranth and increase the effectiveness of selection in the program by identifying the correlation and path coefficients between yield and its relevant attributes. On 120 genotypes of amaranth planted during two growing seasons in 2020 and 2021, the study was carried out using an alpha lattice design with two replications. The results revealed significant positive phenotypic and genotypic associations on leaf yield, with leaf area, leaf breadth, branch number, leaf number, plant height at flowering, and grain yield all having positive direct effects. Similar strong positive phenotypic and genotypic relationships were found for grain yield and grain sink filling rates. Using path coefficient analysis, the direct and indirect effects of yield-related traits on yield were also determined. In addition to having a strong direct impact on grain output, the grain sink filling rates showed both phenotypic and genotypic evidence of substantial positive relationships with grain yield. It was further suggested that leaf yield in amaranth genotypes may increase through the indirect selection of plant height at maturity, leaf length, and terminal inflorescence lateral length, which showed such significant indirect influences, mostly through leaf area, days to maturity, and days to emergence, which displayed such strong indirect effects, primarily through plant height at flowering. This study consequently shows the need for traits with significant positive indirect impacts via leaf area to be considered indirect selection criteria for improving leaf yield in amaranth genotypes. The grain sink filling rate also significantly improved grain yield indirectly at both the phenotypic and genotypic levels, mainly via days to flowering and leaf yield. This demonstrated that selection that mainly targeted days to flowering, leaf yield, and grain sink filling rate would ultimately boost the grain yield in amaranth genotypes.
仅基于产量进行选择可能无法有效提高植物育种计划的产量。因此，为了在选择过程中取得遗传进展，除了产量外，还应考虑潜在的产量贡献性状。本研究的目的是通过鉴定产量与其相关性状之间的相关性和通径系数，来提高苋菜的基因型并提高该计划的选择效果。在 2020 年和 2021 年两个生长季节种植的 120 个苋菜基因型上进行了这项研究，采用了具有两个重复的阿尔法格子设计。结果表明，叶产量与叶面积、叶宽、分枝数、叶数、开花期株高和籽粒产量之间存在显著的正表型和基因型关联，所有这些都具有正向的直接效应。籽粒产量和籽粒库充实率之间也存在相似的强正表型和基因型关系。通过通径系数分析，还确定了与产量相关的性状对产量的直接和间接影响。除了对籽粒产量有很强的直接影响外，籽粒库充实率还表现出与籽粒产量有显著正相关的表型和基因型证据。进一步表明，苋菜基因型的叶产量可能通过间接选择成熟株高、叶长和顶生花序侧枝长度来增加，这些性状具有显著的间接影响，主要通过叶面积、成熟天数和出苗天数来实现，这些性状表现出很强的间接效应，主要通过开花期株高来实现。因此，本研究表明，需要考虑具有显著正间接影响的性状作为间接选择标准，以提高苋菜基因型的叶产量。籽粒库充实率也在表型和基因型水平上显著间接提高籽粒产量，主要通过开花天数和叶产量。这表明，主要针对开花天数、叶产量和籽粒库充实率的选择最终将提高苋菜基因型的籽粒产量。
