TaFDL2‐1A confers drought stress tolerance by promoting ABA biosynthesis, ABA responses, and ROS scavenging in transgenic wheat

Abstract

Plants have developed various protective mechanisms to survive drought stress. Previously, it was shown that a wheat bZIP transcription factor gene TaFD-Like2-1A (TaFDL2-1A) can confer drought tolerance in Arabidopsis. However, the biological functions related to drought stress tolerance of TaFDL2-1A in wheat (Triticum aestivum L.) remain unclear. In the present study, overexpression of TaFDL2-1A in the wheat cultivar Fielder improved drought resistance and conferred abscisic acid (ABA) hypersensitivity. Further analysis showed that overexpression of TaFDL2-1A increased the hypersensitivity of stomata to drought stress and endogenous ABA content under drought conditions. Genetic analysis and transcriptional regulation analysis indicated that TaFDL2-1A binds directly to the promoter fragments of TaRAB21s and TaNCED2s via ACGT core cis-elements, thereby activating their expression, leading to enhanced ABA responses and endogenous ABA accumulation. In addition, our results demonstrate that overexpression of TaFDL2-1A results in higher SOD and GPX activities in wheat under drought conditions by promoting the expression of TaSOD1 and TaGPx1-D, indicating enhanced reactive oxygen species (ROS) scavenging. These results imply that TaFDL2-1A positively regulates ABA biosynthesis, ABA responses, and ROS scavenging to improve drought stress tolerance in transgenic wheat. Our findings improve our understanding of the mechanisms that allow the wheat bZIP transcription factor to improve drought resistance and provide a useful reference gene for breeding programs to enhance drought resistance.

Exogenous abscisic acid and sodium nitroprusside regulate flavonoid biosynthesis and photosynthesis of Nitraria tangutorum Bobr in alkali stress

“…In this study, alkali stress of 30–100 mM resulted in significant increases in the contents of H 2 O 2 , O 2 -, MDA, and EL, which caused serious oxidative damage to N. tangutorum seedlings and significantly reduced the growth indicators, such as plant height, fresh weight(FW), relative water content(RWC), and degree of succulent(DS) ( Figure 1 ). It has been found that multiple environmental stresses stimulate the generation of endogenous ABA and NO in plants, such as drought and alkali stress that induce significant ABA accumulation in wheat and maize, respectively ( Ma et al., 2018 ; Wang et al., 2022 ), which promoted their adaptability to the adverse environment through regulating photosynthesis, antioxidant pathways, ion balance and other pathways. It has been reported that exogenous application of ABA or SNP can effectively promote the production of ABA or NO in plants and reduce the damage caused by stress, such as Brassica pekinensis ( Ren et al., 2020 ), Sorghum bicolor ( Sun et al., 2019 ), and Medicago sativa ( Li, X et al, 2020 ).…”

“…Ten seedlings were analyzed for every treatment, repeated five times. We selected 100 mM alkaline stress as the follow-up experiment ( Wang et al., 2022 ).…”

BpGRP1 acts downstream of BpmiR396c/BpGRF3 to confer salt tolerance in Betula platyphylla

“…The stress-inducible gene BpGRP1 plays a positive role in salt stress tolerance Marked changes in physiology, metabolism and, most notably, gene expression always occur when plants respond to adversity (Gupta et al, 2020;Wang et al, 2022a). Prior research has demonstrated that stress-inducible genes are expressed at higher levels in plants accustomed to coping with salt stress (Li et al, 2022;Xing et al, 2020), and these genes include GRP genes (Tada et al, 2019).…”

Effects of Drought and Flooding on Phytohormones and Abscisic Acid Gene Expression in Kiwifruit

“…Given that Arabidopsis is an annual herbaceous weed, whilst citrus and kiwifruit are woody perennials from the Rosid and Asterid dicot superclades, respectively, this is indicative of a highly conserved response in eudicots that is likely to be key in overcoming drought stress. Furthermore, experiments with transgenic lines of two monocots, wheat and rice, showed that increased drought tolerance was associated with elevated ABA sensitivity, resulting in greater endogenous ABA accumulation [29,30]. This suggests that the role of ABA in drought tolerance may be conserved across angiosperms as a whole.…”