Elevated temperature and waterlogging decrease cottonseed quality by altering the accumulation and distribution of carbohydrates, oil and protein

Abstract

Soil waterlogging and high-temperature events have occurred simultaneously in recent years in the Yangtze River basin cotton belt region of China, negatively affecting the development and quality of cottonseed. This study investigated the effects of the combination of elevated temperature (ET) (34.1/29.0 C) and waterlogging (3 or 6 days) on the accumulation and distribution of oil, protein and carbohydrates in cottonseed during flowering and boll development. The results showed that ET resulted in greater decreases in cottonseed biomass under waterlogging than under control conditions. The combination of waterlogging and ET significantly limited the accumulation of carbohydrates and oil contents. However, ET promoted protein accumulation and compensated for the negative effects of 3-day waterlogging on the final protein content. The combined ET and 6-day waterlogging significantly decreased the final contents of oil and protein by limiting carbon flux and NADPH supply because of the decreased activities of phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) and glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49). The PEPC activity was correlated more with protein content than oil content. In addition, simultaneous exposure to waterlogging and ET resulted in lower unsaturated fatty acid/saturated fatty acid ratios and essential amino acid/non-essential amino acid ratios than did exposure to the individual factors alone. These findings could provide the theoretical support for the prospective assessment of effects of high temperature and waterlogging stresses on cotton production under climate change, and they can help to develop effective techniques in cotton cultivation.

ABA Biosynthesis and Signaling Cascades Under Hypoxia Stress

“…Due to the excessive water absorption, hypoxia mechanically damages seed germination, seedling establishment, and finally crop yield (Nakayama et al, 2004 ; Arguello et al, 2016 ; Yanjun et al, 2016 ; Striker and Colmer, 2017 ; Wang et al, 2017 ; Shen et al, 2020 ; Lee et al, 2021 ; Tian et al, 2021 ). Further, flooding decreases the seed quality of cotton and soybean by altering the accumulation and distribution of carbohydrates, oil, and protein (Wang et al, 2018 ; Xu et al, 2021 ). Collectively, hypoxia stress negatively regulates numerous aspects of plant development.…”

Effects of elevated air temperature coupling with soil drought on carbohydrate metabolism and oil synthesis during cottonseed development

“…Considerable amounts of hexose accumulate in the early developing seed, and higher hexose concentration has a beneficial effect on lipid accumulation. It has been demonstrated that the cleavage of sucrose and the rapid accumulation of hexoses were the pre‐storage steps for seed development and oil synthesis (Li et al, 2016; Xu et al, 2021). Noticeably, a previous report indicated that oil concentration in cottonseed kernels was jointly determined by maximal velocity ( V max ) and the peak value of kernel oil accumulation, in which about 70%–80% of the total oil content was contributed by the rapid accumulation period (Yang et al, 2018).…”

“…Considerable amounts of hexose accumulate in the early developing seed, and higher hexose concentration has a beneficial effect on lipid accumulation. It has been demonstrated that the cleavage of sucrose and the rapid accumulation of hexoses were the pre-storage steps for seed development and oil synthesis (Li et al, 2016;Xu et al, 2021).…”

Aerenchyma formation in the root of leaf‐vegetable sweet potato: Programmed cell death initiated by ethylene‐mediated H2O2 accumulation

“…Waterlogging induces ABA accumulation and the expression of the ethylene response factor RAP2.6 , which leads to an increase in ROS that are toxic chemicals, causing oxidative damage to DNA, proteins and lipids (Hinz et al 2010). Plants have evolved a series of morphological and physiological response mechanisms to help them survive flood (Ayi et al 2016; Xu et al 2021; Zhang et al 2016). For example, in deep water rice with strong waterlogging tolerance, ethylene can promote internode elongation by promoting GA and ABA synthesis and help some organs escape from the submergence environment (Nishiuchi et al 2012).…”