Department of Horticulture and Landscape Architecture, Colorado State University, Fort Collins, CO, 80523-1173, USA.
Plant Cell Environ. 2015 Apr;38(4):710-7. doi: 10.1111/pce.12429. Epub 2014 Sep 26.
Transpiration is controlled by evaporative demand and stomatal conductance (gs ), and there can be substantial genetic variation in gs . A key parameter in empirical models of transpiration is minimum stomatal conductance (g0 ), a trait that can be measured and has a large effect on gs and transpiration. In Arabidopsis thaliana, g0 exhibits both environmental and genetic variation, and quantitative trait loci (QTL) have been mapped. We used this information to create a genetically parameterized empirical model to predict transpiration of genotypes. For the parental lines, this worked well. However, in a recombinant inbred population, the predictions proved less accurate. When based only upon their genotype at a single g0 QTL, genotypes were less distinct than our model predicted. Follow-up experiments indicated that both genotype by environment interaction and a polygenic inheritance complicate the application of genetic effects into physiological models. The use of ecophysiological or 'crop' models for predicting transpiration of novel genetic lines will benefit from incorporating further knowledge of the genetic control and degree of independence of core traits/parameters underlying gs variation.
蒸腾作用受蒸发需求和气孔导度（gs）的控制，gs 存在大量的遗传变异。蒸腾作用经验模型中的一个关键参数是最小气孔导度（g0），这是一种可以测量的特征，对 gs 和蒸腾作用有很大影响。在拟南芥中，g0 表现出环境和遗传变异，并已定位到数量性状位点（QTL）。我们利用这些信息创建了一个遗传参数化的经验模型来预测基因型的蒸腾作用。对于亲本系，这个模型效果很好。然而，在重组自交群体中，预测结果的准确性降低。当仅基于单个 g0 QTL 的基因型时，基因型的区分度不如模型预测的那么高。后续实验表明，基因型与环境互作和多基因遗传使得遗传效应在生理模型中的应用变得复杂。为了预测新遗传系的蒸腾作用，使用生理生态或“作物”模型将受益于进一步了解 gs 变异的核心特征/参数的遗传控制和独立性程度。
