Performance of soft red winter wheat subjected to field soil waterlogging: Grain yield and yield components

Soil waterlogging impacts 25% of the global area planted to wheat and the development of waterlogging tolerant cultivars lags behind progress that has been made for other abiotic stresses. This study was conducted to identify sources of waterlogging tolerance in soft red winter wheat (SRWW) adapted to the southeastern United States, a region prone to yearly waterlogging. A set of 28 SRWW genotypes were evaluated over two growing seasons in field waterlogging experiments at the Rice Research and Extension Center in Stuttgart, Arkansas. Waterlogging at the late tillering stage resulted in a mean grain yield (GY) reduction of 34%, ranging from 16 to 49% within the tested lines. Total GY was impacted by lower kernel weight spike(-1) resulting from reductions in kernels spike(-1) and 1000 kernel weight, total biomass and to a lesser extent spike density. An interaction between genotype and the waterlogging treatment (GxT) was observed for days to heading, plant height, kernel weight spike(-1), kernels spike(-1) and 1000 kernel weight with significant GxT detected for total GY during the first season only. Spectral reflectance measurements of normalized difference vegetative index were highly predictive of both GY (R-2 = 0.77) and total biomass (R-2 = 0.64) under waterlogging but not in the control, indicating potential for indirect high-throughput screening and selection. Overall, the genotypes 26R22, AR01167-3-1, Magnolia and USG 3555 had significantly higher GY than other genotypes under waterlogging, with USG 3555 also showing a non-significant GY reduction, indicating its potential as a genetic source of waterlogging tolerance. (C) 2016 Elsevier B.V. All rights reserved.