Trehalose can alleviate decreases in grain number per spike caused by low‐temperature stress at the booting stage by promoting floret fertility in wheat

Abstract

Alleviating the negative effects of low temperature at the booting stage on wheat grain number and yield is important for maintaining high and stable wheat yields.In this study, we selected wheat varieties with different levels of cold resistance, simulated low temperature at the booting stage and exogenously applied trehalose to study its effect on wheat floret development under low-temperature stress and explore the physiological mechanism of that process. The results showed that higher levels of endogenous trehalose benefited wheat resistance to low-temperature stress.Exogenous trehalose inhibited floret degeneration and increased floret fertility in the apical spikelets, thus significantly alleviating the decrease in grain number per spike caused by low temperature. The results of the metabolomics analysis as well as the physiological indexes showed that trehalose significantly promoted the assimilation of nitrogen in florets under low-temperature stress, thus reducing the accumulation of ammonium ions in the plant cells. In addition, exogenous trehalose significantly increased the endogenous spermidine level in florets, increased their glutathione and ascorbic acid contents, promoted the glutathione-ascorbic acid cycle, and thereby reduced the contents of reactive oxygen species in florets. This may be an important physiological mechanism by which trehalose alleviates the effect of low-temperature stress on floret development in wheat.

The trehalose 6‐phosphate phosphatase family in plants

“…Furthermore, overexpression of a translational fusion of the E. coli TPS and TPP genes in rice led to higher trehalose content and increased tolerance to low temperatures by reducing photo‐oxidative damage (Garg et al, 2002; Jang et al, 2003). A similar protective mechanism was proposed by Liu et al (2020) in tomato and Liang et al (2021) in wheat plants treated with trehalose and then subjected to low temperatures, which displayed significant increases in the expression and activity of enzymes and levels of metabolites related to the antioxidant defence system. As trehalose treatment reduced membrane lipid peroxidation and alleviated the inhibition of plant growth caused by cold stress, it was hypothesized that enhanced trehalose content leads to enhanced cold stress tolerance by regulating the antioxidant defence system.…”

Mechanistic Insights Into Trehalose-Mediated Cold Stress Tolerance in Rapeseed (Brassica napus L.) Seedlings

“…In another study, seed priming with Tre and Tre + spermidine significantly improved the seed vigor and the growth of the cold-stressed rice seedlings ( Fu et al, 2020 ). In wheat, exogenous Tre inhibited floret degeneration and improved the floret fertility in the apical spikelets, thereby considerably lowering the grain number per spike under CS conditions ( Liang et al, 2021 ). The report in the rapeseed also supports the protective role of Tre in advancing the plant growth and production under adverse environmental conditions, mainly under CS conditions.…”

“…In the recent years, limited studies have been carried out using exogenous Tre to enhance CS tolerance in different plant species, such as tomato ( Solanum lycopersicum L.) ( Liu et al, 2020 ), rice ( Oryza sativa L.) ( Fu et al, 2020 ), wheat ( Tritum aestivum L.) ( Liang et al, 2021 ), melon ( Cucumis melo L.) ( Liu et al, 2021 ), etc., and the mechanisms mediating Tre effects have not been fully discovered. Most importantly, the effect of exogenous Tre in improving the CS tolerance in rapeseed ( Brassica napus L.) is still unclear.…”

Comparative Physiology and Transcriptome Analysis of Young Spikes in Response to Late Spring Coldness in Wheat (Triticum aestivum L.)

“…Some organisms have a higher tolerance to LT stress due to the accumulation of large amounts of trehalose in the tissue (Zhao et al, 2018). A recent study showed that exogenous trehalose could promote the floret fertility of wheat and alleviate the reduction of grain number per spike caused by LT stress at the booting stage (Liang et al, 2021). The metabolic pathway of trehalose formation comprises two phases.…”