Pathogen Identification and Fungicide Selection for Leaf Spot Disease on Plectranthus scutellarioides in Fujian
-
摘要:
目的 明确福建省彩叶草(Plectranthus scutellarioides)叶部病害的病原种类,筛选可用于病害防控的化学药剂。 方法 采用常规组织分离法获得病原菌株并进行柯赫氏法则验证,结合形态学与分子生物学(ITS与LSU序列)对分离菌株进行鉴定,采用生长速率法测定6种杀菌剂对该病原菌的室内毒力。 结果 用分离菌株ZZCYC1706分生孢子接种彩叶草,侵染叶片症状与田间症状相似;形态特征及ITS和LSU多基因序列分析表明,该病原菌为链格孢(Alternaria alternata)。供试6种药剂室内毒力测定结果显示,96%啶菌恶唑抑菌效果最好,其EC50为0.621 μg·mL−1,其次为98%异菌脲和95%嘧霉胺,EC50分别为1.155 、5.258 μg·mL−1;而96.4%克菌丹效果较差,EC50值最高,为89.010 μg·mL−1。 结论 福建漳州彩叶草叶斑病病原菌鉴定为链格孢(A. alternata),该发现为国内首次报道。啶菌恶唑、异菌脲和嘧霉胺对该病原菌的毒力较高,并分属不同药剂类型,可用于链格孢引起叶斑病的防治。 Abstract:Objective Identification of the leaf spot pathogen on Plectranthus scutellarioides in Fujian and screening fungicides for effective disease prevention and control were conducted. Method A causative pathogen was isolated from the diseased tissues, and the species verified by Koch’s rule, morphological observations under a microscope, and molecular ITS and LSU sequence analyses. An in vitro toxicity test on 6 commercially available fungicides was performed on the pathogen to determine their efficacy. Result The coleus leaves inoculated with the conidia of the isolated ZZCYC1706 produced same symptoms as those observed on the diseased plants in the field. The ITS and LSU sequences of ZZCYC1706 suggested it be Alternaria alternata. The toxicity test showed, among the 6 fungicides, 96% pyrisoxazole to be most effective in inhibiting the pathogenic growth with the lowest EC50 of 0.621 μg·mL−1. It was followed by 98% iprodione with an EC50 at 1.155 μg·mL−1 , 95% pyrimethanil at 5.258 μg·mL−1, and 96.4% captan, which was the least effective, at 89.010 μg·mL−1. Conclusion The pathogen of the leaf spot disease on P. scutellarioides in Fujian province was identified as A. alternata, which was the first reported in China. The fungicides, pyrisoxazole, iprodione, and pyrimethanil, were shown in the laboratory effective in inhibiting the growth of A. alternata. And, being of different types, these fungicides could potentially be applicable for the coleus leaf spot disease control with a reduced concern of the development of drug resistance by the pathogen. -
Key words:
- Plectranthus scutellarioides /
- leaf spot /
- Alternaria alternata /
- toxicity test /
- EC50
-
图 2 菌落形态和致病性鉴定
注:A,生长3 d的菌落形态;B,生长10 d的正面菌落形态;C,生长10 d的反面菌落形态;D,接种对照叶片(3 d);E,分生孢子接种叶片(3 d)
Figure 2. Colony morphology and pathogenic assay
Note: A: Colony on PDA after 3 d incubation; B: Colony top-view after 10 d incubation; C: Colony bottom-view after 10 d incubation; D: Control leaf after 3 d incubation; E: Artificially inoculated leaf after 3 d incubation.
图 4 基于ITS和LSU序列构建链格孢属系统发育树
注:分支上的数字标示Bootstrap 检验的支持率,大丽轮枝菌(V. dahliae)作为外群,ZZCYC1706为分离菌株
Figure 4. Phylogenetic tree of Alternaria spp. based on ITS and LSU sequences
Note: Data shown at each node are confidence values from 1 000 replicate bootstrap samplings; Verticillium dahliae was out group, while ZZCYC1706, isolate.
表 1 6种药剂对彩叶草叶斑病病原菌的毒力测定
Table 1. Toxicities of 6 fungicides on A. alternata
药剂
Fungicide回归方程
Regression
equation相关系数r
Correlation
coefficient, rEC50值
EC 50 Value/
(µg·mL−1)95%嘧霉胺
95%Pyrimethanily=0.994x+3.647 0.985 5.258 98%异菌脲
98% Iprodioney=0.827x+4.962 0.984 1.155 96.4%克菌丹
96.4% Captany=0.427x+3.085 0.917 89.010 96%啶菌恶唑
96% Pyrisoxazoley=0.386x+5.184 0.999 0.621 99%腐霉利
99% Procymidoney=0.535x+2.929 0.995 48.120 96%啶酰菌胺
96% Boscalidy=0.566x+2.884 0.998 42.210 -
[1] SUVA M A, A M PATEL, N SHARMA. Coleus species: Solenostemon scutellarioides [J]. J Inventi Rapid:Planta Activa, 2015(2): 1−5. [2] 李东霞, 宋妍, 王彩凤, 等. 药用植物彩叶草的研究进展 [J]. 生命的化学, 2021, 41(4):680−685.LI D X, SONG Y, WANG C F, et al. Research progress on the medicinal plant Plectranthus scutellarioides [J]. Chemistry of Life, 2021, 41(4): 680−685.(in Chinese) [3] ROOSITA K, KUSHARTO C M, SEKIYAMA M, et al. Medicinal plants used by the villagers of a Sundanese community in West Java, Indonesia [J]. Journal of ethnopharmacology, 2008, 115(1): 72−81. doi: 10.1016/j.jep.2007.09.010 [4] LEVITA J, SUMIWI S A, PRATIWI T I, et al. Pharmacological activities of Plectranthus scutellarioides (L. ) R. Br. leaves extract on cyclooxygenase and xanthine oxidase enzymes [J]. Journal of Medicinal Plants Research, 2016, 10(20): 261−269. [5] CRETTON S, SARAUX N, MONTEILLIER A, et al. Anti-inflammatory and antiproliferative diterpenoids from Plectranthus scutellarioides [J]. Phytochemistry, 2018, 154: 39−46. doi: 10.1016/j.phytochem.2018.06.012 [6] SWAMY M K, U R SINNIAH, A GHASEMZADEH. Anticancer potential of rosmarinic acid and its improved production through biotechnological interventions and functional genomics [J]. Appl Microbiol Biotechnol, 2018, 102(18): 7775−7793. doi: 10.1007/s00253-018-9223-y [7] 方梅玉. 漳州市花卉、苗木产业现状及发展方向 [J]. 福建热作科技, 2019, 44(4):60−64. doi: 10.3969/j.issn.1006-2327.2019.04.020FANG M Y. Current status and development direction of flower and seedling industry in Zhangzhou [J]. Fujian Science & Technology of Tropical Crops, 2019, 44(4): 60−64.(in Chinese) doi: 10.3969/j.issn.1006-2327.2019.04.020 [8] DENTON G J, BEAL E, DENTON J O, et al. First record of downy mildew, caused by Peronospora belbahrii, on Solenostemon scutellarioides in the UK [J]. New Disease Reports, 2015, 31(1): 14−14. doi: 10.5197/j.2044-0588.2015.031.014 [9] ITO Y, TAKEUCHI T, MATSUSHITA Y, et al. Downy mildew of coleus caused by Peronospora belbahrii in Japan [J]. Journal of general plant pathology, 2015, 81(4): 328−330. doi: 10.1007/s10327-015-0601-3 [10] GORAYEB E S, PIERONI L P, CRUCIOL G C D, et al. First report of downy mildew on coleus (Plectranthus spp. ) caused by Peronospora belbahrii sensu lato in Brazil [J]. Plant Disease, 2020, 104(1): 294. [11] GARIBALDI A, BERTETTI D, POLI A, et al. First report of Verticillium wilt caused by Verticillium dahliae on Coleus verschaffeltii in Italy [J]. Plant disease, 2011, 95(7): 878−878. [12] GARIBALDI A, BERTETTI D, MATIĆ S, et al. First report of leaf necrosis caused by Alternaria alternata on Plectranthus scutellarioides in Italy [J]. Plant Disease, 2020, 104(2): 590−590. [13] 王文. 彩叶草的栽培与病虫防治 [J]. 中国林副特产, 2012(4):77.WANG W. Cultivation and Control of Diseases and Pests on Plectranthus scutellarioides [J]. Forest By-Product and Speciality in China, 2012(4): 77.(in Chinese) [14] 陈丹, 张纯, 阮煜. 观叶花卉彩叶草的繁殖方法及栽培技术 [J]. 安徽农业科学, 2015(16):30−31,62.CHEN D, ZHANG C, RUAN Y. Colored Grass Breeding Methods and Cultivation Techniques [J]. Journal of Anhui Agricultural Sciences, 2015(16): 30−31,62.(in Chinese) [15] 陈少萍. 彩叶草栽培管理 [J]. 中国花卉园艺, 2020(3):64−65.CHEN S P. Cultivation and management on Plectranthus scutellarioides [J]. China Flowers & Horticulture, 2020(3): 64−65.(in Chinese) [16] 田忠锋, 荣梅, 王秀玲. 彩叶草栽培及管理技术浅析 [J]. 农村实用技术, 2020(5):49.TIAN Z F, RONG M, WANG X L. Analysis on cultivation and management techniques of Plectranthus scutellarioides [J]. Nongcun Shiyong Jishu, 2020(5): 49.(in Chinese) [17] 李本金, 陈庆河, 兰成忠, 等. 福建省大豆根腐病病原菌的鉴定 [J]. 福建农业学报, 2011, 26(5):798−803. doi: 10.3969/j.issn.1008-0384.2011.05.024LI B J, CHEN Q H, LAN C Z, et al. A identification and pathogenicity test of the pathogens causing soybean root rot in Fujian [J]. Fujian Journal of Agricultural Sciences, 2011, 26(5): 798−803.(in Chinese) doi: 10.3969/j.issn.1008-0384.2011.05.024 [18] 席中刚, 游景茂, 郑露, 等. 湖北省黄连叶斑病病原鉴定及其生物学特性 [J]. 植物保护学报, 2018, 45(2):315−321.XI Z G, YOU J M, ZHENG L, et al. Identification and biological characteristics of the pathogen causing leaf spot on Coptis chinensis in Hubei Province [J]. Journal of Plant Protection, 2018, 45(2): 315−321.(in Chinese) [19] LAWRENCE D P, F ROTONDO, P B GANNIBAL. Biodiversity and taxonomy of the pleomorphic genus Alternaria [J]. Mycological Progress, 2016, 15(1): 1−22. doi: 10.1007/s11557-015-1147-7 [20] DOYLE J J, DOYLE J L. A rapid DNA isolation procedure for small quantities of fresh leaf tissue [J]. Phytochem Bull, 1987, 19: 11−15. [21] WOUDENBERG J H C, SEIDL M F, GROENEWALD J Z, et al. Alternaria section Alternaria: Species, formae speciales or pathotypes? [J]. Studies in mycology, 2015, 82: 1−21. doi: 10.1016/j.simyco.2015.07.001 [22] 王荣波, 陈姝樽, 刘裴清, 等. 荔枝霜疫霉中双组分信号转导系统的鉴定与表达分析 [J]. 植物病理学报, 2020, 50(1):49−59.WANG R B, CHEN S Z, LIU P Q, et al. Identification and expression analysis of two-component signaling system-related genes in Peronophythora litchi [J]. Acta Phytopathologica Sinica, 2020, 50(1): 49−59.(in Chinese) [23] 常红洋, 王荣波, 李本金, 等. 防治荔枝霜疫霉病的药剂筛选及田间应用 [J]. 农药, 2018, 57(2):137−138,142.CHANG H Y, WANG R B, LI B J, et al. Effective fungicides screening and field application for litchi downy blight [J]. Agrochemicals, 2018, 57(2): 137−138,142.(in Chinese) [24] 李永, 岳志强, 朴春根, 等. 链格孢属真菌的分子复核鉴定及系统发育研究 [J]. 中国农学通报, 2013(27):165−169. doi: 10.3969/j.issn.1000-6850.2013.27.029LI Y, YUE Z Q, PU C G, et al. Molecular identification and phylogeny of genus Alternaria [J]. Chinese Agricultural Science Bulletin, 2013(27): 165−169.(in Chinese) doi: 10.3969/j.issn.1000-6850.2013.27.029 [25] PINTO V E F, PATRIARCA A. Alternaria species and their associated mycotoxins [M]. New York: Humana Press, 2017: 13-32. [26] 张丹华, 张红楠, 吴頔, 等. 重庆地区枇杷叶斑病病原初步鉴定及防治药剂室内筛选 [J]. 中国南方果树, 2017, 46(4):102−106, 111.ZHANG D H, ZHANG H N, WU D, et al. Identification of The Pathogen Causing Loquat Leaf-spot Disease and The Screening of Fungicides [J]. South China Fruits, 2017, 46(4): 102−106, 111.(in Chinese) [27] 王彩霞, 李兴红, 魏艳敏, 等. 引起葡萄叶斑病的链格孢种类的初步鉴定 [J]. 植物保护学报, 2019, 46(1):175−183.WANG C X, LI X H, WEI Y M, et al. Identification of Alternaria species causing leaf spots in grapes [J]. Journal of Plant Protection, 2019, 46(1): 175−183.(in Chinese) [28] SUN, H F, WEI M Y, LI N, et al. First report of Alternaria alternata causing leaf spot on Menispermum dauricum DC. in China[J]. Plant Disease, 2021. doi: 10.1094/PDIS-07-21-1447-PDN. [29] LI S, SHEN Q, WANG H, et al. First report of Alternaria alternata causing leaf spot of Tartary Buckwheat (Fagopyrum tataricum) in China[J]. Plant Disease, 2021. doi: 10.1094/PDIS-01-21-0191-PDN. [30] ZHANG Q, ZHANG Y, SHI H, et al. First report of leaf spot caused by Alternaria alternata on Yucca gloriosa in China[J]. Plant Disease, 2021. doi: 10.1094/PDIS-04-21-0857-PDN [31] ZHONG F T, LIU Y L, ZHENG D, et al. First report of Alternaria alternata causing brown leaf spot on wild rice (Oryza rufipogon) in China[J]. Plant Disease, 2021. doi: 10.1094/PDIS-05-21-1024-PDN. [32] 赵炽娜, 胡津瑜, 王云萍, 等. 申嗪霉素对4种链格孢属植物病原真菌的室内毒力测定 [J]. 长江大学学报(自然科学版), 2020, 17(1):74−77.ZHAO Z N, HU J Y, WANG Y P, et al. Indoor toxicity test of phenazine-1-carboxylic acid to 4 species of Alternaria plant pathogenic fungi [J]. Journal of Yangtze University(Natural Science Edition), 2020, 17(1): 74−77.(in Chinese)