枯草芽胞杆菌TR21喷叶对粉蕉根系分泌酚酸的影响

为探索枯草芽胞杆菌TR21喷叶对广粉1号和粉杂1号粉蕉根系酚酸分泌的影响,测定了不同处理不同时间根系分泌物中的酚酸含量,并利用高效液相色谱测定第13天的根系分泌物中的酚酸组成,以及甲醇溶解物对香蕉枯萎病病原菌1号和4号生理小种孢子萌发的影响。结果显示,广粉1号TR21处理后4d和6d根系酚酸分泌量高于对照,处理后8、9、11、13d低于对照;TR21处理粉杂1号根系酚酸分泌量始终高于对照。广粉1号对照根系处理后13d分泌物中检测到阿魏酸、反式肉桂酸、芥子酸、对香豆酸、水杨酸和邻苯二甲酸,TR21处理仅检测到阿魏酸和反式肉桂酸;粉杂1号对照和TR21处理后13d的根系分泌物只检测到阿魏酸。不同处理的甲醇溶解酚酸显著抑制香蕉枯萎病1号生理小种小型分生孢子萌发,粉杂1号的抑制效果比广粉1号明显,TR21处理的粉杂1号抑制效果最显著。甲醇溶解酚酸对4号生理小种的分生孢子也有显著抑制作用,但不同处理间差异不显著。TR21喷叶可以改变粉蕉根系酚酸的分泌,但在抗感品种中引起的变化存在差异。

Effects of Bacillus subtilis strain TR21 spraying leaves on secretion of phenolic acids in drawf banana (Musa spp. ABB) root exudates

In order to explore the phenolic acids secretion of drawf bananaMusa spp. ABB Guangfen No .1 and Fenza No .1 seedlings after spraying by Bacillus subtilis strain TR21, the root exudates were collected at different days after treated and the contents of phenolic acids were tested. The components of phenolic acids at the 13th day were detected by High performance liquid chromatography (HPLC), and the effects of methanol dissolved phenolic acids on the microconidia germination of Fusarium oxysporum f. sp. cubense race 1 and race 4 were tested. The results showed that TR21 treatment increased root phenolic acids secretion of Guangfen No.1 at the 4th and 6th day, but decreased it at the 8th, 9th, 11th and 13th day, TR21 treatment increased the phenolic acids secretion of Fenza No.1 at all tested times. Seven kinds of free phenolic acids, including ferulic acid, trans-cinnamic acid, sinapic acid, p-coumaric acid, salicylic acid and alizaric acid were found in control Guangfen No.1 root exudates, but only ferulic acid and trans-cinnamic acid were found in TR21 treated. Ferulic acid was the only detected free phenolic acid in Fenza No.1 root exudates. The methanol dissolved phenolic acids reduced the race 1 microconidia germination significantly, especially those from TR21 treated Fenza No.1. Methanol dissolved phenolic acids also reduced race 4 microconidia germination, but there was no difference among different treatments. It was concluded that TR21 spraying leaves really changed the root phenolic acids secretion of drawf banana, but there were differences in resistant and susceptive variety.