Plant growth rate after, and not during, waterlogging better correlates to yield responses in wheat and barley

Abstract

Waterlogging is a stress that affects wheat (Triticum aestivum L.) and barley (Hordeum vulgare L. ssp. distichum) yield. This work aimed at analysing the impact of a waterlogging event during pre-anthesis (critical period) on yield, its numerical components and their relationships with plant growth rate in wheat and barley. Two pot experiments were carried out under contrasting environmental conditions (early and late sowing date), in which six wheat and six barley cultivars were exposed to control and waterlogging conditions imposed c. 18 days prior to anthesis. Measurements included total above-ground biomass at the beginning and at the end of the waterlogging treatment and at maturity, when grain yield and its numerical components were also measured. Wheat showed higher yield losses (−76%) due to waterlogging than barley (−49%). Grain yield was explained by both numerical components (the number of grains per plant and grain weight), which better correlated with the relative growth rate of plants during the post-stress recovery than during the waterlogging period. Plant growth during the recovery period should be targeted as a key factor to estimate yield losses from waterlogging in these cereals.