Molecular Phytopathology and Mycotoxin Research Unit, Department of Crop Sciences, Goettingen University, 37077 Göttingen, Germany.
J Plant Res. 2009 Sep;122(5):571-9. doi: 10.1007/s10265-009-0237-5. Epub 2009 May 16.
Salicylic acid (SA) and its glucoside (SAG) were detected in xylem sap of Brassica napus by HPLC-MS. Concentrations of SA and SAG in xylem sap from the root and hypocotyl of the plant, and in extracts of shoots above the hypocotyl, increased after infection with the vascular pathogen Verticillium longisporum. Both concentrations were correlated with disease severity assessed as the reduction in shoot length. Furthermore, SAG levels in shoot extracts were correlated with the amount of V. longisporum DNA in the hypocotyls. Although the concentration of SAG (but not SA) in xylem sap of infected plants gradually declined from 14 to 35 days post infection, SAG levels remained significantly higher than in uninfected plants during the whole experiment. Jasmonic acid (JA) and abscisic acid (ABA) levels in xylem sap were not affected by infection with V. longisporum. SA and SAG extend the list of phytohormones potentially transported from root to shoot with the transpiration stream. The physiological relevance of this transport and its contribution to the distribution of SA in plants remain to be elucidated.
通过高效液相色谱-质谱法，在油菜木部汁液中检测到水杨酸（SA）及其糖苷（SAG）。在感染维管束病原体长蠕孢菌后，植物根部和下胚轴的木质部汁液以及下胚轴上方嫩枝的提取物中 SA 和 SAG 的浓度增加。两种浓度都与作为嫩枝长度减少的疾病严重程度相关。此外，嫩枝提取物中的 SAG 水平与下胚轴中长蠕孢菌 DNA 的量相关。尽管感染植物的木质部汁液中 SAG（但不是 SA）的浓度从感染后 14 天到 35 天逐渐下降，但在整个实验过程中，SAG 水平仍明显高于未感染植物。木质部汁液中茉莉酸（JA）和脱落酸（ABA）的水平不受长蠕孢菌感染的影响。SA 和 SAG 将潜在从根部运输到茎部的植物激素清单扩展到蒸腾流中。这种运输的生理相关性及其对植物中 SA 分布的贡献仍有待阐明。
