Boatwright J Lucas, Sapkota Sirjan, Myers Matthew, Kumar Neeraj, Cox Alex, Jordan Kathleen E, Kresovich Stephen
Advanced Plant Technology, Clemson University, Clemson, SC, United States.
Department of Plant and Environmental Sciences, Clemson University, Clemson, SC, United States.
Front Plant Sci. 2022 May 18;13:790005. doi: 10.3389/fpls.2022.790005. eCollection 2022.
Carbon partitioning in plants may be viewed as a dynamic process composed of the many interactions between sources and sinks. The accumulation and distribution of fixed carbon is not dictated simply by the sink strength and number but is dependent upon the source, pathways, and interactions of the system. As such, the study of carbon partitioning through perturbations to the system or through focus on individual traits may fail to produce actionable developments or a comprehensive understanding of the mechanisms underlying this complex process. Using the recently published sorghum carbon-partitioning panel, we collected both macroscale phenotypic characteristics such as plant height, above-ground biomass, and dry weight along with microscale compositional traits to deconvolute the carbon-partitioning pathways in this multipurpose crop. Multivariate analyses of traits resulted in the identification of numerous loci associated with several distinct carbon-partitioning traits, which putatively regulate sugar content, manganese homeostasis, and nitrate transportation. Using a multivariate adaptive shrinkage approach, we identified several loci associated with multiple traits suggesting that pleiotropic and/or interactive effects may positively influence multiple carbon-partitioning traits, or these overlaps may represent molecular switches mediating basal carbon allocating or partitioning networks. Conversely, we also identify a carbon tradeoff where reduced lignin content is associated with increased sugar content. The results presented here support previous studies demonstrating the convoluted nature of carbon partitioning in sorghum and emphasize the importance of taking a holistic approach to the study of carbon partitioning by utilizing multiscale phenotypes.
植物中的碳分配可被视为一个动态过程，该过程由源和库之间的诸多相互作用组成。固定碳的积累和分配并非仅由库强度和数量决定，而是取决于系统的源、途径及相互作用。因此，通过对系统进行扰动或聚焦于个体性状来研究碳分配，可能无法产生可付诸行动的进展，也无法全面理解这一复杂过程背后的机制。利用最近发表的高粱碳分配面板，我们收集了宏观尺度的表型特征，如株高、地上生物量和干重，以及微观尺度的组成性状，以解析这种多用途作物中的碳分配途径。对性状的多变量分析导致鉴定出许多与几个不同碳分配性状相关的基因座，这些基因座可能调节糖含量、锰稳态和硝酸盐运输。使用多变量自适应收缩方法，我们鉴定出几个与多个性状相关的基因座，这表明多效性和/或相互作用效应可能对多个碳分配性状产生积极影响，或者这些重叠可能代表介导基础碳分配或划分网络的分子开关。相反，我们还发现了一种碳权衡，即木质素含量降低与糖含量增加相关。此处呈现的结果支持了先前的研究，这些研究证明了高粱中碳分配的复杂性质，并强调了通过利用多尺度表型对碳分配研究采取整体方法的重要性。
