Liu Huai-Pan, Zhu Zi-Xue, Liu Tian-Xue, Li Chao-Hai
Henan Key Laboratory of Crop Growth and Development Regulation, Henan Agricultural University, Zhengzhou 450002, China.
Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao. 2006 Jun;32(3):293-9.
The changes in levels and forms of polyamine (Pa) in the coleoptiles of two wheat (triticum aestivum L.) cultivars differing in drought tolerance were investigated under osmotic stress. The drought-tolerant 'Yumai 18' showed marked increases in free spermidine (Spd) and spermine (Spm) levels in coleoptiles after being treated with polyethylene glycol (PEG)-6000 for 2 d in the dark, while drought-sensitive 'Yangmai 9' showed a significant increase in free putrescine (Put) content. Treatment of coleoptiles with methylglyoxal-bis (guanylhydrazone) (MGBG), an S-adenosylmethionine decarboxylase (S-AMDC) inhibitor, resulted in reduction of free Spd and free Spm levels in coleoptiles and aggravation of PEG-induced injury to 'Yumai 18' coleoptile, while exogenous Spd treatment resulted in an increase in free Spd + free Spm content of coleoptiles, and an alleviation of PEG-induced injury to 'Yangmai 9' coleoptile. Osmotic stress induced significant increases in perchloric acid-soluble conjugated PA (PS conjugated PA) and perchloric acid-insoluble conjugated PA (PIS conjugated PA) levels in coleoptiles of 'Yumai 18' whereas osmotic stress affected only slightly the PS-conjugated PA and PIS-conjugated PA levels in 'Yangmai 9' coleoptiles. Treatment of coleoptiles with phenanthroline (o-Phen), an inhibitor of transglutaminase (TGase), also aggravated the PEG-induced injury to 'Yumai 18' coleoptiles, accompanied by the decreases in the level of PIS-conjugated PA. These results suggest that free Spd, free Spm and conjugated PA enhance the osmotic stress tolerance of wheat coleoptiles.
在渗透胁迫条件下，研究了两个耐旱性不同的小麦（普通小麦）品种胚芽鞘中多胺（Pa）的含量及形态变化。耐旱品种‘豫麦18’在黑暗中用聚乙二醇（PEG）-6000处理2 d后，胚芽鞘中游离亚精胺（Spd）和精胺（Spm）含量显著增加，而干旱敏感品种‘扬麦9号’的游离腐胺（Put）含量显著增加。用S-腺苷甲硫氨酸脱羧酶（S-AMDC）抑制剂甲基乙二醛双（脒基腙）（MGBG）处理胚芽鞘，导致‘豫麦18’胚芽鞘中游离Spd和游离Spm含量降低，加重了PEG对‘豫麦18’胚芽鞘的伤害，而外源Spd处理则使‘扬麦9号’胚芽鞘中游离Spd + 游离Spm含量增加，减轻了PEG对‘扬麦9号’胚芽鞘的伤害。渗透胁迫使‘豫麦18’胚芽鞘中高氯酸可溶性结合态PA（PS结合态PA）和高氯酸不溶性结合态PA（PIS结合态PA）含量显著增加，而渗透胁迫对‘扬麦9号’胚芽鞘中PS结合态PA和PIS结合态PA含量影响较小。用转谷氨酰胺酶（TGase）抑制剂邻菲罗啉（o-Phen）处理胚芽鞘，也加重了PEG对‘豫麦18’胚芽鞘的伤害，同时PIS结合态PA含量降低。这些结果表明，游离Spd、游离Spm和结合态PA增强了小麦胚芽鞘对渗透胁迫的耐受性。
