The mitochondrion conformation and the contents of conjugated polyamines were investigated using theembryos of developing wheat (Triticum aestivum L.) grains of two cultivars differing in drought toleranceas experiment materials. After drought stress treatment for 7 days, the relative water content of embryoand relative increase rate of embryo dry weight of the drought-sensitive Yangmai No. 9 cv. decreased moresignificantly than those of the drought-tolerant Yumai No. 18 cv. Furthermore, the changes in mitochondrionconformation of Yangmai No. 9 were more marked. Meanwhile, the increases of the contents ofconjugated non-covalently spermidine (CNC-Spd) and conjugated covalently putrescine (CC-Put) of YumaiNo. 18 were more obvious than those of Yangmai No. 9. Treatment with exogenous Spd not onlyalleviated the injury of drought stress to Yangmai No. 9, but also enhanced the increase of CNC-Spdcontent and inhibited the change in the mitochondrion conformation of this cultivar. The treatments ofYumai No. 18 with two inhibitors, methylglyoxyl-bis (guanylhydrazone) and phenanthrolin, significantlyinhibited the drought stress-induced increases of CNC-Spd and CC-Put contents of the cultivar, respectively.Meanwhile, the treatments with the two inhibitors aggravated the injury of drought stress to YumaiNo. 18 and enhanced the change in the mitochondrion conformation of this cultivar. These results mentionedabove suggested that the CNC-Spd and CC-Put in embryo mitochondrion membrane isolated fromdeveloping grains could enhance the wheat tolerance to drought stress by maintaining the mitochondrionconformation.
Volume 46, 2021
Continuous Article Publishing mode
Click here for Editorial Note on CAP Mode