Lopez Miguel Angel, Freitas Moreira Fabiana, Rainey Katy Martin
Colombian Sugarcane Research Center, Cali, Colombia.
Bayer CropScience (United States), St. Louis, MI, United States.
Front Plant Sci. 2021 Apr 9;12:651241. doi: 10.3389/fpls.2021.651241. eCollection 2021.
Soybean grain yield has steadily increased during the last century because of enhanced cultivars and better agronomic practices. Increases in the total biomass, shorter cultivars, late maturity, and extended seed-filling period are frequently reported as main contributors for better soybean performance. However, there are still processes associated with crop physiology to be improved. From the theoretical standpoint, yield is the product of efficiency of light interception (), radiation use efficiency (), and harvest index (). The relative contribution of these three parameters on the final grain yield (), their interrelation with other phenological-physiological traits, and their environmental stability have not been well established for soybean. In this study, we determined the additive-genetic relationship among 14 physiological and phenological traits including photosynthesis () and intrinsic water use efficiency () in a panel of 383 soybean recombinant inbred lines (RILs) through direct (path analyses) and indirect learning methods [least absolute shrinkage and selection operator (LASSO) algorithm]. We evaluated the stability of , , and through the slope from the Finley and Wilkinson joint regression and the genetic correlation between traits evaluated in different environments. Results indicate that both supervised and unsupervised methods effectively establish the main relationships underlying changes in , , , and . Variations in the average growth rate of canopy coverage for the first 40 days after planting () explain most of the changes in . is primarily influenced by phenological traits of reproductive length () and seed-filling () as well as , light extinction coefficient (), and . showed a strong relationship with , , , and . According to the path analysis, an increase in one standard unit of promotes changes in 0.5 standard units of , while changes in the same standard unit of and produce increases on of 0.20 and 0.19 standard units, respectively. , , and exhibited better environmental stability than , although changes associated with year and location showed a moderate effect in and , respectively. This study brings insight into a group of traits involving , , and to be prioritized during the breeding process for high-yielding cultivars.
在上个世纪，由于品种改良和更好的农艺措施，大豆籽粒产量稳步提高。总生物量增加、植株变矮、成熟延迟以及灌浆期延长等因素常被认为是大豆产量提高的主要原因。然而，与作物生理相关的一些过程仍有待改进。从理论角度来看，产量是光截获效率（）、辐射利用效率（）和收获指数（）的乘积。对于大豆而言，这三个参数对最终籽粒产量（）的相对贡献、它们与其他物候 - 生理性状的相互关系以及它们的环境稳定性尚未得到很好的确立。在本研究中，我们通过直接（通径分析）和间接学习方法[最小绝对收缩和选择算子（LASSO）算法]，在一组383个大豆重组自交系（RILs）中确定了14个生理和物候性状之间的加性遗传关系，这些性状包括光合作用（）和内在水分利用效率（）。我们通过Finley和Wilkinson联合回归的斜率以及在不同环境中评估的性状之间的遗传相关性，评估了、和的稳定性。结果表明，有监督和无监督方法都有效地建立了、、和变化背后的主要关系。种植后前40天冠层覆盖平均生长速率（）的变化解释了大部分的变化。主要受生殖长度（）和灌浆（）的物候性状以及、消光系数（）和的影响。与、、和显示出很强的关系。根据通径分析，一个标准单位的增加会促进0.5个标准单位的变化，而相同标准单位的和的变化分别会使增加0.20和0.19个标准单位。、和表现出比更好的环境稳定性，尽管与年份和地点相关的变化分别对和有中等程度的影响。本研究为高产大豆品种育种过程中涉及、和的一组性状提供了深入见解，这些性状应被优先考虑。
