First Report of Phytopythium vexans Causing Root Rot on Quercus bicolor in Tennessee and the United States.

IF 4.4 2区 农林科学 Q1 PLANT SCIENCES
Cansu Oksel, Pratima Subedi, Prabha Liyanapathiranage, Batu Arik, Farhat A Avin, Terri Simmons, Fulya Baysal-Gurel
{"title":"First Report of <i>Phytopythium vexans</i> Causing Root Rot on <i>Quercus bicolor</i> in Tennessee and the United States.","authors":"Cansu Oksel, Pratima Subedi, Prabha Liyanapathiranage, Batu Arik, Farhat A Avin, Terri Simmons, Fulya Baysal-Gurel","doi":"10.1094/PDIS-11-24-2355-PDN","DOIUrl":null,"url":null,"abstract":"<p><p>Swamp white oak (<i>Quercus bicolor</i>) is a North American species of medium-sized trees in the beech family. One-year-old swamp white oak seedlings grown in field conditions in a commercial nursery in Warren County, Tennessee exhibited severe root rot in July 2024. Dark brown lesions were observed in the affected roots (Fig. 1a). Disease severity was approximately 40% of root area affected, and disease incidence was approximately 20% of 100 plants. Symptomatic fine root tissues were surface sterilized with 70% ethanol and rinsed twice with distilled water. Then, symptomatic root parts (1-cm pieces) were plated on V8-PARPH (V8 juice agar amended with pimaricin, ampicillin, rifampicin, pentachloronitrobenzene, and hymexazol) and incubated at 24°C under an 8-hour photoperiod. The rosette pattern accompanied by whitish mycelium resembling <i>Phytopythium</i> species was consistently observed after three days of incubation. Sporangia were globose or subglobose (19.11±1.71 μm, <i>n</i>=50) with or without papilla (Fig. 1b). Oogonia were smooth, filamentous to globose (21.04±1.74 μm, <i>n</i>=50) (Fig. 1c). Representative isolates (FBG7779-1 and FBG7779-2) were identified as <i>Phytopythium vexans</i> based on morphological characterization (de Cock et al. 2015; Ghimire and Baysal-Gurel 2023). To confirm pathogen identity, total DNA was extracted using the DNeasy PowerLyzer Microbial Kit from 7-day-old cultures of the isolates grown on V8-PARPH. The primer pairs ITS1/ITS4 (White et al. 1990), NL1/NL4 (Baten et al. 2014), OomCoxI-Levup/Fm85mod (Robideau et al. 2011), and Cox2-F/Cox2-R (Hudspeth et al. 2000) were used to amplify and sequence the ribosomal internal transcribed spacer (ITS), the large subunit (LSU), and the mitochondrial cytochrome c oxidase subunits I (CoxI) and II (CoxII) genetic markers, respectively. The ITS, LSU, CoxI and CoxII sequences of the isolates FBG7779-1 and FBG7779-2 (ITS: PQ567140 and PQ567141; LSU: PQ567376 and PQ567377; CoxI: PQ570510 and PQ570511; CoxII: PQ570512, and PQ570513) were 100% identical to those of <i>P. vexans</i> isolates MK011115, OQ754108, GU133478, and AB468910, respectively. To complete Koch's postulates, pathogenicity test was performed on two-year-old swamp white oak seedlings (165 to 170 cm height) grown in 3-gal containers. The plants were drench inoculated with pathogen slurry (150 ml per plant - two 9-cm plates of 7-day-old culture/liter) of the isolates FBG7779-1 and FBG7779-2 (five plants per isolate) (Panth et al. 2021). Five plants were drenched with agar slurry without the pathogen and served as a non-inoculated control plant. The study was conducted in a greenhouse condition (21 to 23°C, 70% relative humidity) and irrigated twice a day for 2 min each time using an overhead irrigation system. Two weeks after inoculation, dark brown lesions developed in the roots of all inoculated plants (Fig. 1d), whereas controls remained healthy (Fig. 1e). The morphology of the pathogen isolated on the V8-PARPH medium was identical to the original isolate and confirmed by sequencing the ITS, LSU, CoxI and CoxII markers. Phytopythium vexans has been previously reported to cause root and crown rot in flowering cherry, ginkgo, red maple, and redbud in Tennessee (Baysal-Gurel et al. 2021; Liyanapathiranage et al. 2023; Panth et al. 2021). To our knowledge, this is the first report of <i>P. vexans</i> causing root rot of swamp white oak in Tennessee and the United States. Identifying the pathogen as the causal agent is crucial in the development of a successful disease management strategy of <i>P. vexans</i> on swamp white oak.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4000,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plant disease","FirstCategoryId":"97","ListUrlMain":"https://doi.org/10.1094/PDIS-11-24-2355-PDN","RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 0

Abstract

Swamp white oak (Quercus bicolor) is a North American species of medium-sized trees in the beech family. One-year-old swamp white oak seedlings grown in field conditions in a commercial nursery in Warren County, Tennessee exhibited severe root rot in July 2024. Dark brown lesions were observed in the affected roots (Fig. 1a). Disease severity was approximately 40% of root area affected, and disease incidence was approximately 20% of 100 plants. Symptomatic fine root tissues were surface sterilized with 70% ethanol and rinsed twice with distilled water. Then, symptomatic root parts (1-cm pieces) were plated on V8-PARPH (V8 juice agar amended with pimaricin, ampicillin, rifampicin, pentachloronitrobenzene, and hymexazol) and incubated at 24°C under an 8-hour photoperiod. The rosette pattern accompanied by whitish mycelium resembling Phytopythium species was consistently observed after three days of incubation. Sporangia were globose or subglobose (19.11±1.71 μm, n=50) with or without papilla (Fig. 1b). Oogonia were smooth, filamentous to globose (21.04±1.74 μm, n=50) (Fig. 1c). Representative isolates (FBG7779-1 and FBG7779-2) were identified as Phytopythium vexans based on morphological characterization (de Cock et al. 2015; Ghimire and Baysal-Gurel 2023). To confirm pathogen identity, total DNA was extracted using the DNeasy PowerLyzer Microbial Kit from 7-day-old cultures of the isolates grown on V8-PARPH. The primer pairs ITS1/ITS4 (White et al. 1990), NL1/NL4 (Baten et al. 2014), OomCoxI-Levup/Fm85mod (Robideau et al. 2011), and Cox2-F/Cox2-R (Hudspeth et al. 2000) were used to amplify and sequence the ribosomal internal transcribed spacer (ITS), the large subunit (LSU), and the mitochondrial cytochrome c oxidase subunits I (CoxI) and II (CoxII) genetic markers, respectively. The ITS, LSU, CoxI and CoxII sequences of the isolates FBG7779-1 and FBG7779-2 (ITS: PQ567140 and PQ567141; LSU: PQ567376 and PQ567377; CoxI: PQ570510 and PQ570511; CoxII: PQ570512, and PQ570513) were 100% identical to those of P. vexans isolates MK011115, OQ754108, GU133478, and AB468910, respectively. To complete Koch's postulates, pathogenicity test was performed on two-year-old swamp white oak seedlings (165 to 170 cm height) grown in 3-gal containers. The plants were drench inoculated with pathogen slurry (150 ml per plant - two 9-cm plates of 7-day-old culture/liter) of the isolates FBG7779-1 and FBG7779-2 (five plants per isolate) (Panth et al. 2021). Five plants were drenched with agar slurry without the pathogen and served as a non-inoculated control plant. The study was conducted in a greenhouse condition (21 to 23°C, 70% relative humidity) and irrigated twice a day for 2 min each time using an overhead irrigation system. Two weeks after inoculation, dark brown lesions developed in the roots of all inoculated plants (Fig. 1d), whereas controls remained healthy (Fig. 1e). The morphology of the pathogen isolated on the V8-PARPH medium was identical to the original isolate and confirmed by sequencing the ITS, LSU, CoxI and CoxII markers. Phytopythium vexans has been previously reported to cause root and crown rot in flowering cherry, ginkgo, red maple, and redbud in Tennessee (Baysal-Gurel et al. 2021; Liyanapathiranage et al. 2023; Panth et al. 2021). To our knowledge, this is the first report of P. vexans causing root rot of swamp white oak in Tennessee and the United States. Identifying the pathogen as the causal agent is crucial in the development of a successful disease management strategy of P. vexans on swamp white oak.

美国及田纳西州双色栎根腐病研究初报。
沼泽白栎(Quercus bicolor)是北美山毛榉科的一种中等大小的树木。2024年7月,在田纳西州沃伦县的一个商业苗圃中,在田间条件下生长的一岁沼泽白栎幼苗出现了严重的根腐病。在受影响的根部观察到深棕色病变(图1a)。病害严重程度约占受影响根面积的40%,100株中病害发生率约为20%。有症状的细根组织用70%乙醇表面消毒,用蒸馏水冲洗2次。然后,将有症状的根部分(1cm片)镀于V8- parph (V8果汁琼脂,用海马西林、氨苄西林、利福平、五氯硝基苯和噻虫唑修饰)上,在24℃下光照8小时。在3天的孵育后,一致地观察到莲座图案伴随着类似植菌的白色菌丝体。孢子囊呈球形或亚球形(19.11±1.71 μm, n=50),有或没有乳突(图1b)。卵原体光滑,呈丝状至球状(21.04±1.74 μm, n=50)(图1c)。代表性分离株FBG7779-1和FBG7779-2经形态学鉴定为vexans植物菌(de Cock et al. 2015;Ghimire and Baysal-Gurel 2023)。为了确认病原体的身份,使用DNeasy PowerLyzer微生物试剂盒从V8-PARPH上生长的7天培养的分离株中提取总DNA。利用引物对ITS1/ITS4 (White et al. 1990)、NL1/NL4 (Baten et al. 2014)、OomCoxI-Levup/Fm85mod (Robideau et al. 2011)和cox - f / cox - r (Hudspeth et al. 2000)分别对核糖体内转录间隔物(ITS)、大亚基(LSU)和线粒体细胞色素c氧化酶亚基I (CoxI)和II (CoxII)遗传标记进行扩增和测序。分离株FBG7779-1和FBG7779-2的ITS、LSU、CoxI和CoxII序列(ITS: PQ567140和PQ567141;LSU: PQ567376和PQ567377;CoxI: PQ570510和PQ570511;CoxII: PQ570512和PQ570513)与vexans分离株MK011115、OQ754108、GU133478和AB468910的基因序列完全一致。为了完成Koch的假设,对在3加仑容器中生长的两岁沼泽白栎树幼苗(165至170厘米高)进行了致病性测试。用分离株FBG7779-1和FBG7779-2(每个分离株5株)的病原菌浆液(每株150 ml -两个9厘米板7日龄培养物/升)对植株进行淋接种(Panth et al. 2021)。用不含病原菌的琼脂浆浸泡5株,作为未接种的对照植株。研究在温室条件下进行(21至23°C, 70%相对湿度),每天灌溉两次,每次灌溉2分钟,使用架空灌溉系统。接种两周后,所有接种植株的根部都出现了深棕色病变(图1d),而对照组保持健康(图1e)。在V8-PARPH培养基上分离到的病原菌形态与原分离物完全相同,并通过ITS、LSU、CoxI和CoxII标记测序证实。此前曾有报道称,在田纳西州的开花樱桃、银杏、红枫和紫荆中,植物霉会导致根部和冠腐病(Baysal-Gurel等人,2021;Liyanapathiranage等,2023;Panth et al. 2021)。据我们所知,这是在田纳西州和美国引起沼泽白栎树根腐病的第一份报告。确定该病原菌为致病因子对于制定成功的沼泽白栎树vexans病害管理策略至关重要。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Plant disease
Plant disease 农林科学-植物科学
CiteScore
5.10
自引率
13.30%
发文量
1993
审稿时长
2 months
期刊介绍: Plant Disease is the leading international journal for rapid reporting of research on new, emerging, and established plant diseases. The journal publishes papers that describe basic and applied research focusing on practical aspects of disease diagnosis, development, and management.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信