Exogenous application of glycine betaine improved water use efficiency in winter wheat (Triticum aestivum L.) via modulating photosynthetic efficiency and antioxidative capacity under conventional and limited irrigation conditions

This study was conducted to explore the role of exogenously applied GB in improving WUE and plant physiological and biochemical responses in winter wheat subjected to conventional or limited irrigation during the 2015–2016 and 2016–2017 growing seasons. Exogenous application of GB significantly enhanced antioxidant enzyme activities and reduced the accumulation of malondialdehyde and hydrogen peroxide under limited irrigation conditions. Furthermore, GB-treated plants maintained higher leaf relative water content and membrane stability, which led to higher chlorophyll content and gas exchange attributes for better intrinsic and instantaneous water use efficiencies compared to control plants under limited irrigation conditions. GB-treated plants had higher indole-acetic acid and zeatin riboside levels but lower ABA levels compared to control plants under conventional and limited irrigation conditions. Additionally, GB enhanced the grain filling rate and duration, grain number per spike, and final grain weight, which resulted in higher grain yield compared to the control. Interestingly, GB significantly improved the integrative and photosynthetic WUE under conventional and limited irrigation conditions, although GB treatment did not markedly affect total water consumption. These results suggest the involvement of GB in improving WUEs in winter wheat by modulating hormonal balance, membrane stability, photosynthetic performance and antioxidant systems to maintain higher grai...
Source: The Crop Journal - Category: Food Science Source Type: research