Page 77 - 《广西植物》2023年第7期
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7 期 程小卿等: 内生真菌 Alternaria sp. GHX ̄P17 代谢产物防治广藿香青枯病及保护酶的变化 1 2 4 5
( 1. Laboratory of Germplasm Resources and Molecular Identification of Traditional Chinese Medicineꎬ School of Pharmaceutical Sciencesꎬ
Guangzhou University of Chinese Medicineꎬ Guangzhou 510006ꎬ Chinaꎻ 2. Pharmacy Centerꎬ Yangchun
Traditional Chinese Medicine Hospitalꎬ Yangchun 529600ꎬ Guangdongꎬ China )
Abstract: There is a long history to cultivate the Pogostemon cablin in Guangdong Provinceꎬ and it is a famous
medicinal material. The bacterial wilt is the important disease that impacts the production and quality of P. cablin.
Aiming to the control effects of metabolites of Alternaria sp. GHX ̄P17 strain that is belonging to an endophytic fungus
isolated from the stems and leaves of P. cablin and the mechanism of disease resistance on bacterial wiltꎬ a laboratory
experiment had been conducted to investigate the incidence and severity of bacterial wilt in P. cablin at different time
after artificial to inoculate the strain of Alternaria sp. GHX ̄P17 and to spray the crude extracts of the metabolitesꎬ and
disease index (DI) was calculated. The activity changes of protective enzymes of phenylalanine ammonia lyase (PAL)ꎬ
peroxidase (POD) and superoxide dismutase (SOD) were determined in different time in P. cablin. The results were as
follows: (1) The DI was significantly lower in the treatment groups with the crude extracts of Alternaria sp. GHX ̄P17 at
different concentrations than that of control groupsꎬ and the DI decreased by 27.16% in the treatment groups at 204 h
after inoculation. The variance analysis showed significant differences (P<0.05). (2) The severity of bacterial wilt was
reduced with the extension of investigation time in P. cablinꎬ and the severity levels increased slowly in treatment
groups. The average severity was significantly lower than that of the control groups at 204 hꎬ and the control effects
reached 74.65%. (3) The activities of protective enzymes of PALꎬ POD and SOD increased observably after to inoculate
spore suspension and to spray metabolites in P. cablinꎬ but the activity peak time was different. PAL activities gradually
increased after inoculationꎻ POD first increased and then decreasedꎬ and then increased againꎬ and there were two the
activity peaksꎻ SOD increased rapidly and then decreased gradually. Obviouslyꎬ the metabolites of Alternaria sp. GHX ̄
P17 can not only increase the activities of protective enzymes in P. cablinꎬ and delay the infection process of Ralstonia
solanacearumꎬ but also decrease the severity levels of bacterial wilt. Howeverꎬ the research findings provide a reference
for the study of active components of secondary metabolites of endophytic fungi and the development of biopesticides.
Key words: endophytic fungiꎬ metabolitesꎬ control effectsꎬ bacterial wiltꎬ Pogostemon cablinꎬ protective enzymes
广藿香(Pogostemon cablin)为唇形科刺蕊草属 欣悦等(2020)从烟草根际分离出 2 株拮抗细菌菌
一年生草本植物ꎬ干燥全草可入药ꎬ是著名南药ꎬ 株 GZYCT ̄4 和 GZYCT ̄9 用于防治室内烟草青枯
具有芳香化浊ꎬ开胃止呕ꎬ发表解暑之功效( 李薇 病ꎬ具有一定的防效ꎮ Hanemian 等( 2013) 用 hrp
和徐鸿华ꎬ 2003)ꎮ 新的临床研究发现ꎬ以广藿香 基因插入突变获得的无致病力青枯菌突变株ꎬ番
为主打成分的宣肺败毒基础方剂在预防新型冠状 茄青枯病病情显著降低ꎮ
病毒肺炎(COVID ̄19) 方面也有不错的疗效( 王钏 内生菌因长期定殖于宿主植物组织内与宿主
等ꎬ2020ꎻ徐旭等ꎬ2020)ꎮ 生产上ꎬ广藿香青枯病 协同进化ꎬ二者形成了一种非常复杂的共生关系ꎬ
(bacterial wilt)是威胁广藿香生产和质量的主要病 并影响着宿主植物各种成分的积累和对胁迫的应
害ꎬ每年减产 30% ~ 80%ꎮ 广藿香青枯病是由茄科 激反应(Cley & Schardiꎬ 2002)ꎮ 几乎所有被研究
雷尔氏菌(Ralstonia solanacearum)引起的一种细菌 过的植物中均能检测到内生菌的存在ꎬ这些内生
性病害ꎬ该菌被认为是热带与亚热带地区最重要 菌分布广且具有丰富的生物多样性ꎮ 药用植物是
的病原细菌之一ꎬ可危害多种作物ꎮ 茄科雷尔氏 挖掘活性内生菌资源的重要宝库ꎬ其内生菌群落
菌主要从根部伤口入侵ꎬ穿过皮层进入维管束ꎬ产 组成丰度、定殖率、分离频率、优势种群数量超过
生侵填体(tylose)和胼胝质(callose) 堵塞导管和筛 其他非药用植物ꎮ 目前ꎬ已从铁皮石斛( Dendro ̄
管ꎬ引起寄主青枯死亡ꎮ 青枯病属于土传病害ꎬ较 bium officinale) ( 胡 克 兴 等ꎬ 2010ꎻ 周 琢 艳 等ꎬ
难防治ꎬ除常规的农业防治和化学防治外ꎬ多人也 2017)、 甘 草 ( Glycyrrhiza uralensis ) ( 陈 静 等ꎬ
从生防角度对青枯病防治进行了研究ꎮ 例如ꎬ烟 2019)、 杜 仲 ( Eucommia ulmoides) ( 梁 雪 娟 等ꎬ
草作为典型青枯病指示植物( indicative plant)ꎬ张 2014)、拐枣(Hovenia acerba) ( Gao et al.ꎬ 2005)、