Key phenotypes related to wheat grain yield in a two‐site multicultivar test

Abstract

AbstractYield performances of wheat (Triticum aestivum L.) cultivars are decided by the combined effects of key phenotypes. However, it is unclear which phenotypes are the key phenotypes that determine yield. We conducted a two‐site multicultivar test in Henan and Anhui in China during the 2016‒2017 wheat growing season. The objectives were to assess the relationships between grain yield and other related phenotypes and reveal the key phenotypes related to grain yield. Grain yield and nineteen phenotypes were assessed in a field trial consisting of 28 wheat cultivars. Multivariate statistical analysis methods (e.g., principal component analysis, partial least squares model, structural equation model) were used to reveal the relationships between grain yield and other related phenotypes. Wheat phenotypes changed as a result of the differences in environment (site) and genotype (cultivar). Eleven phenotypes were identified as the key phenotypes closely related to grain yield: biomass, harvest index, spike density, leaf nitrate reductase, net photosynthetic rate, canopy temperature, leaf chlorophyll, leaf area index, stomatal conductance, carboxylation efficiency, and transpiration rate. For analyzing the mechanisms of yield differences, multiple related phenotypes (rather than a single phenotype) should be considered.