杨树膜脂脂肪酸和磷脂的组成与抗寒性的关系

对一年生草本植物小麦、水稻、玉米等从生物膜膜脂的组成和配比的角度来探讨抗寒机理已有很多的报告,对多年生木本植物的研究还不很多。以前的研究结果大部分都支持了脂肪酸不饱和度与抗寒性的相关性,但各种植物也不尽相同,甚至有一些相反的结论。为了比较杨树耐寒品种和不耐寒品种在化学和生理特性上的差别,本研究用现代仪器分析方法测定了耐寒欧美杨(45杨)和不耐寒美洲黑杨(69杨)的膜脂总脂肪酸、磷脂组分的配比和总磷脂含量,为判别杨树无性系新品种的抗寒能力提供了依据。

RELATIONSHIP BETWEEN THE COMPOSITIONS OF FATTY ACIDS AND PHOSPHOLIPIDS IN MEMBRANE LIPID AND THE CHILLING-RESISTANCE OF POPLAR

The fatty acids and the phospholipids in membrane lipid of two poplarvarieties: chill-resistant P. euramericana cl. I-45/51 and chill-sensitive P.deltoides Bartr. cv. "Lux"I-69/55 were analysed. There is an evident differe-nce in the unsaturated degrees of the fatty acids between the two Varieties,linoleic acid is the dominant component in the chill-resistant variety, whilepalmitic acid is the major one in the chill-sensitive variety. Index ofUnsaturation of Fatty Acid (IUFA) can be used as a standard to evaluate thechilling resistance of poplar. The phospholipid compositions in two varietiesare similar, they are phosphatidyl choline (PC), phosphatidyl inositol (PI),phosphatidyl ethanolamine (PE), and phosphatidyl glycerol (PG). There areno apparent differences in the distribution of the four phospholipid componentsand the total content of phospholipid between these two varieties, so phospho-lipid composition can not be used as a standard of chilling resistance for po-plar.