Response of bread-wheat seedlings to waterlogging stress

Waterlogging is a widespread problem and one of the major yield-limiting factors of wheat in some parts of the coastal plains of Turkey. The object of this study was to identify waterlogging-tolerant cultivars in bread wheat. Twenty-four bread-wheat genotypes were tested under aerobic and anaerobic conditions to determine shoot dry weight gain, root dry weight gain, total dry weight gain, dry leaf weight, specific dry leaf weight, chlorophyll content, carotenoid content, transpiration and photosynthesis rates, and their tolerance indices. A complete randomized block design with three replications was conducted for both aerobic and anaerobic conditions. The current study clearly demonstrated that wheat seedlings growing under anaerobic conditions had significantly lower shoot dry weight, root dry weight, total dry biomass weight, leaf dry weight, specific leaf dry weight, chlorophyll a, chlorophyll b, chlorophyll a + b, and carotenoid content, and photosynthesis and transpiration rates. There were significant correlations between total dry weight gain and shoot dry weight gain and between chlorophyll a and specific leaf dry weight. Wheat cultivars had different tolerance indices for the investigated plant parameters. Further studies are needed to confirm which tolerance index is significantly correlated with seed yield and which one could be used as a selection criterion under field conditions.