抑制水稻细菌性条斑病菌的没食子酸分离及其对水稻细菌性条斑病的防治作用

通过液—液萃取、硅胶和凝胶柱层析法,从佛甲草(Sedum lineare)分离出一种可以抑制水稻细菌性条斑病菌(Xanthomonas oryzae pv.oryzicola,Xoc)生长的单体化合物,经质谱分析,确定该化合物为没食子酸(gallic acid,GA)。在30 mg·m L-1浓度下,GA能抑制一些植物病原细菌如桃细菌性穿孔病菌(X.campestris pv.pruni)、水稻细菌性条斑病菌(X.oryzae pv.oryzicola)、水稻白叶枯病菌(X.oryzae pv.oryzae)、柑橘溃疡病菌(X.axonopodis pv.citri)、大豆细菌性斑点病菌(Pseudomonas syringae pv.glycinea)、番茄细菌性斑点病菌(P.syringae pv.tomato)和胡萝卜软腐果胶杆菌(Pectobacterium carotovora subsp.carotovora)的生长;GA还对11种植物病原真菌如烟草疫霉(Phytophthora nicotianae)、指状青霉(Penicillium digitatum)、滇刺枣褐腐病菌(Streptobotrys streptothrix)、瓜果腐霉(Pythium aphanidermatum)、芒果拟盘多毛孢(Pestalotiopsis mangiferae)、新月弯孢霉(Curvularia lunata)、立枯丝核菌(Rhizoctonia solani)、(Fusarium oxysporum f.sp.niverum)、西瓜专化型尖孢镰刀菌(F.oxysporum f.sp.nicotianae)、番茄灰霉病菌(Botrytis cinerea)和齐整小核菌(Sclerotium rolfsii)的生长具有一定的抑制作用。在300 mg·m L-1浓度下,GA对水稻细菌性条斑病的田间防治效果达到64.62%。该研究结果表明没食子酸具有开发成为一种防治水稻细菌性条斑病的杀菌剂的潜力。

Gallic acid isolated from Sedum lineare and its control efficacy on rice bacterial leaf streak

A compound, which could significantly inhibit the growth of Xanthomonas oryzae pv. oryzicola(Xoc)in vitro, was isolated from Sedum lineare by liquid-liquid extraction, silica gel column chromatography and gel column chromatography. Based on the spectral data, including ¹H and ¹³C NMR data, this compound was identified as 3,4,5-Trihydroxybenzoic acid, namely gallic acid(GA). The results of the test, on determining the antibiotic spectrum of GA at concentration 30 mg·mL^-1, indicated that GA could most strongly inhibit the growth of X.campestris pv. pruni, X. oryzae pv. oryzicola, X. oryzae pv. oryzae and X. axonopodis pv. citri, with inhibition zones width of 25.33, 24.00, 22.33 and 20.67 mm, respectively, and had fair anti-bacteria activity against Ralstonia Solanacearum, Pseudomonas syringae pv. glycinea, P. syringae pv. tomato and Pectobacterium carotovora subsp. carotovora, with inhibition zones width of 18.00, 12.33, 11.00 and 8.68 mm, respectively. Meanwhile, GA could weakly inhibit the growth of eleven pathogenic fungi, including Phytophthora nicotianae, Penicillium digitatum, Streptobotrys streptothrix, Pythium aphanidermatum, Pestalotiopsis mangiferae, Curvularia lunata, Rhizoctonia solani, Fusarium oxysporum f. sp. niverum, F. oxysporum f. sp. nicotianae, Botrytis cinerea and Sclerotium rolfsii, with inhibition ratio of 56.34%, 54.73%, 38.00%, 29.86, 28.17%, 20.00%, 19.02%, 16.71%, 10.59%, 4.58% and 1.96%, respectively. Growth inhibition exceeding 50% by GA was only observed in Phytophthora nicotianae and Penicillium digitatum. The growth of Botrytis cinerea and Sclerotium rolfsii was slightly inhibited by GA. In potted experiment, gallic acid at 200, 300 and 400 mg·L^-1 provided 63.55%, 71.38% and 77.39% control efficacy to rice bacterial leaf streak, respectively. At concentration of 300 mg·mL^-1, GA could control rice bacterial leaf streak, with control efficacy of 64.62% in field. The study reveals that the gallic acid has the potential to be further developed as a bactericide to control rice bacterial leaf streak.