Phytopathology最新文献_第5页

Relationship Between the Distribution of the Pinewood Nematode (Bursaphelenchus xylophilus) and the Development of Xylem Embolism in the Stems of Japanese Black Pine (Pinus thunbergii) Seedlings Monitored by Magnetic Resonance Imaging. 通过磁共振成像监测日本黑松（Pinus thunbergii）幼苗茎干中松材线虫（Bursaphelenchus xylophilus）的分布与木质部栓塞发展之间的关系。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-01-28 DOI: 10.1094/PHYTO-06-24-0191-R

Ai Akami, Kenji Fukuda

{"title":"Relationship Between the Distribution of the Pinewood Nematode (Bursaphelenchus xylophilus) and the Development of Xylem Embolism in the Stems of Japanese Black Pine (Pinus thunbergii) Seedlings Monitored by Magnetic Resonance Imaging.","authors":"Ai Akami, Kenji Fukuda","doi":"10.1094/PHYTO-06-24-0191-R","DOIUrl":"10.1094/PHYTO-06-24-0191-R","url":null,"abstract":"The development of xylem embolism in 1-year-old stems of Japanese black pine (Pinus thunbergii) seedlings was monitored by compact magnetic resonance imaging (MRI) after inoculation with the pinewood nematode (Bursaphelenchus xylophilus). In parallel, the nematode distribution and population structure in the stems were examined by isolating the nematodes using the Baermann funnel technique. The vertical length and volume of massive embolisms in each seedling were strongly correlated with the maximum relative embolized area (REA) in stem cross-sections. Embolism development and nematode reproduction were not restricted to the inoculation site, as any portion of the stem could be the initial point of a population burst. The nematode population in the stem xylem was strongly correlated with the REA and with the circumferential proportion of cambial death in cross-sections monitored by MRI. The proportion of second-stage juveniles was also correlated with the REA in the xylem. In contrast, the nematode population in bark tissue was not correlated with either the REA or cambial death. These results suggested that nematode reproduction in the cambial zone is the key step in pine wilt disease, and second-stage juveniles were suggested to induce massive embolisms in the advanced stage of the disease.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"172-180"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142381543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Patulin Inhibition of Specific Apple Microbiome Members Uncovers Hanseniaspora uvarum as a Potential Biocontrol Agent. 抑制特定苹果微生物群成员的棒曲霉素发现 Hanseniaspora uvarum 是一种潜在的生物控制剂。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-01-31 DOI: 10.1094/PHYTO-06-24-0189-R

Justin L Eagan, Evan R Digman, Martijn den Boon, Roberto Regalado, Mira S A Rawa, Christina M Hull, Nancy P Keller

{"title":"Patulin Inhibition of Specific Apple Microbiome Members Uncovers Hanseniaspora uvarum as a Potential Biocontrol Agent.","authors":"Justin L Eagan, Evan R Digman, Martijn den Boon, Roberto Regalado, Mira S A Rawa, Christina M Hull, Nancy P Keller","doi":"10.1094/PHYTO-06-24-0189-R","DOIUrl":"10.1094/PHYTO-06-24-0189-R","url":null,"abstract":"Penicillium expansum is a major postharvest pathogen of apples, causing loss in fruits through tissue damage, as well as in apple products due to contamination with the mycotoxin patulin. During infections, patulin is a cultivar-dependent virulence factor that facilitates apple lesion development. Patulin also has characterized antimicrobial activity and is important for inhibiting other competitive phytopathogens, but the role of this inhibitory activity has not been investigated in the context of the apple microbiome. In our current study, we isolated 68 apple microbiota and characterized their susceptibility to P. expansum extracts. We found gram-negative bacteria and basidiomycete yeast to demonstrate largely patulin-specific growth inhibition compared with gram-positive and ascomycete isolates. From co-cultures, we identified a Hanseniaspora and Gluconobacter pairing that reduced P. expansum biomass and found that H. uvarum alone is sufficient to reduce apple disease progression in vivo. We investigated possible mechanisms of H. uvarum biocontrol activity and found modest inhibition on apple puree plates, as well as a trend toward lower patulin levels at the wound site. Active biocontrol activity required live yeast, which was also effective in controlling Botrytis cinerea apple infections. Lastly, we explored the breadth of H. uvarum biocontrol activity with over 30 H. uvarum isolates and found consistent inhibition of P. expansum apple disease.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"117-127"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142381527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Biphenyl and Dibenzofuran Phytoalexins Differentially Inhibit Root-Associated Microbiota in Apple, Including Fungal and Oomycetal Replant Disease Pathogens. 联苯和二苯并呋喃类植物毒素对苹果根部相关微生物群（包括真菌和卵菌再植病病原体）的抑制作用不同。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-02-11 DOI: 10.1094/PHYTO-03-24-0088-R

Belnaser A Busnena, Ludger Beerhues, Benye Liu

{"title":"Biphenyl and Dibenzofuran Phytoalexins Differentially Inhibit Root-Associated Microbiota in Apple, Including Fungal and Oomycetal Replant Disease Pathogens.","authors":"Belnaser A Busnena, Ludger Beerhues, Benye Liu","doi":"10.1094/PHYTO-03-24-0088-R","DOIUrl":"10.1094/PHYTO-03-24-0088-R","url":null,"abstract":"Apple replant disease (ARD) is a serious soilborne disease in apple nurseries and orchards worldwide. ARD is the result of an unbalanced soil microbiome in which multiple soilborne plant-pathogenic fungi, oomycetes, and nematodes form a disease complex. Biphenyl and dibenzofuran phytoalexins are found in greater quantities in the roots of apple plants grown in ARD soil compared with disinfected ARD soil. However, the contribution of these compounds to plant health or disease is not yet understood. Here, the antimicrobial activity of 14 chemically synthesized biphenyl and dibenzofuran phytoalexins was tested against eight selected microorganisms isolated from either rhizosphere soils or apple roots. These included five potentially beneficial bacteria (Rhodococcus pseudokoreensis strain R79T, R. koreensis strain R85, Streptomyces pulveraceus strain ES16, S. ciscaucasicus GS2, and Priestia megaterium strain B1), two ARD fungal pathogens (Ilyonectria robusta H131 and Dactylonectria torresensis N3), and one oomycete (Globisporangium terrestre). Two phytoalexin mixtures reflecting the percentages of the individual compounds inside the roots (mixture A) and the root exudate (mixture B) were also tested. The two phytoalexin mixtures demonstrated higher antimicrobial activity than the individual phytoalexins, suggesting a synergistic effect. The minimum inhibitory concentration and the half-maximal effective concentration values determined to be active against the eight microbes were within a range of 2.5-fold the ecologically relevant phytoalexin concentration (approximately 33 and 24 µg ml-1 in roots and exudate, respectively). The results contribute to our understanding of the impact of apple root phytoalexins on ARD and suggest potential strategies for disease management.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"181-191"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142472980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Systematic Approach for Identifying Unique Genomic Sequences for Fusarium oxysporum f. sp. lactucae Race 1 and Development of Molecular Diagnostic Tools. 确定 Fusarium oxysporum f. sp. lactucae race 1 的独特基因组序列和开发分子诊断工具的系统方法。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-02-07 DOI: 10.1094/PHYTO-04-24-0142-R

Ningxiao Li, David M Geiser, Jacob L Steenwyk, Cayla Tsuchida, Steve Koike, Stephanie Slinski, Frank N Martin

{"title":"A Systematic Approach for Identifying Unique Genomic Sequences for Fusarium oxysporum f. sp. lactucae Race 1 and Development of Molecular Diagnostic Tools.","authors":"Ningxiao Li, David M Geiser, Jacob L Steenwyk, Cayla Tsuchida, Steve Koike, Stephanie Slinski, Frank N Martin","doi":"10.1094/PHYTO-04-24-0142-R","DOIUrl":"10.1094/PHYTO-04-24-0142-R","url":null,"abstract":"Fusarium oxysporum f. sp. lactucae (FOLac) is a soil- and seedborne fungal pathogen that causes Fusarium wilt of lettuce, an important disease threatening global lettuce production. Based on pathogenicity on differential lettuce cultivars, four races (1 to 4) have been identified, with race 1 being the only race detected in the United States and the closely related, emerging race 4 known only in Europe. The development of race-specific diagnostic tools is hindered by insufficient genomic data to distinguish between the two races and FOLac from other F. oxysporum formae speciales and nonpathogenic isolates. Here, we describe a systematic approach for developing diagnostic markers for FOLac race 1 that utilized a comprehensive sequence database of F. oxysporum to identify 15 unique genomic sequences. Marker specificity was validated through an exhaustive screening process against genomic data from 797 F. oxysporum isolates representing 64 formae speciales and various plants and non-plant substrates. One of the unique sequences was used to develop a TaqMan quantitative PCR assay and a recombinase polymerase amplification assay, both exhibiting 100% sensitivity and specificity when tested against purified DNA from 171 F. oxysporum isolates and 69 lettuce samples. The relationship between quantitative PCR cycle threshold values and CFU/g values was also determined. This study not only introduces a new marker for FOLac race 1 diagnostics and soil quantitation but also underscores the value of an extensive genomic database and screening software pipeline for developing molecular diagnostics for F. oxysporum formae speciales and other fungal taxa.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"204-217"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142506494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Canker and Dieback of Alnus rubra Is Caused by Lonsdalea quercina. 红叶石楠的腐烂和枯死是由 Lonsdalea quercina 引起的。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-02-06 DOI: 10.1094/PHYTO-06-24-0192-SC

Fernanda Iruegas-Bocardo, Wendy Sutton, Riley A Buchanan, Niklaus J Grünwald, Jeff H Chang, Melodie L Putnam Retired

{"title":"Canker and Dieback of Alnus rubra Is Caused by Lonsdalea quercina.","authors":"Fernanda Iruegas-Bocardo, Wendy Sutton, Riley A Buchanan, Niklaus J Grünwald, Jeff H Chang, Melodie L Putnam Retired","doi":"10.1094/PHYTO-06-24-0192-SC","DOIUrl":"10.1094/PHYTO-06-24-0192-SC","url":null,"abstract":"Understanding the ecology of pathogens is important for disease management. Recently, a devastating canker disease was found on red alder (Alnus rubra) planted as landscape trees. Bacteria were isolated from two groups of symptomatic trees located approximately 1 km apart, and one strain from each group was used to complete Koch's postulates. The results showed that these bacteria can cause disease not only on red alder but also on two other alder species. Unexpectedly, analyses of genome sequences of bacterial strains identified them as Lonsdalea quercina, a pathogenic species previously known to cause dieback of oak species, but not alder. Additionally, a core genome phylogeny clustered bacterial strains isolated from red alder within a subclade of L. quercina strains isolated from symptomatic oak trees. Consistent with the close phylogenetic relationship, there was no obvious evidence for divergence in genome composition of strains isolated from red alder and oak. Altogether, the findings indicate that L. quercina is a potential threat to Alnus species.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"112-116"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142522710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Functional Characterization of Transcriptional Regulator Rem in Candidatus Liberibacter asiaticus.

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 DOI: 10.1094/PHYTO-10-24-0339-R

Wenting Wang, Jin Xu, Nian Wang

{"title":"Functional Characterization of Transcriptional Regulator Rem in Candidatus Liberibacter asiaticus.","authors":"Wenting Wang, Jin Xu, Nian Wang","doi":"10.1094/PHYTO-10-24-0339-R","DOIUrl":"https://doi.org/10.1094/PHYTO-10-24-0339-R","url":null,"abstract":"Citrus HLB, caused by Candidatus Liberibacter asiaticus (CLas), is the most devastating citrus disease worldwide. Usually 10% of total genes in bacteria are regulatory genes, but only 2% of CLas genes encode transcriptional factors. Here, 20 transcriptional regulators were predicted including eight genes (lsrB, ldtR, rem, visR, visN, ctrA, mucR, pelD, and atoC) directly or indirectly involved in regulating motility, and five genes (i.e., rpoH, prbP, phrR, rirA, and lsrB) involved in oxidative stress response. We demonstrated that rem, lsrB, and visNR of CLas can complement the corresponding mutants of S. meliloti in their reduced motility. We further investigated traits controlled by Rem in S. meliloti and CLas using RNA-seq analyses of rem mutant vs. complementation strains with remSmc or remLas. Transcriptomic analysis showed RemLas significantly regulates the expression of genes in S. meliloti, which was used to infer its regulation of CLas genes by identification of homologous genes. We found Rem is involved in regulating motility, chemotaxis, transporters, and oxidative phosphorylation in S. meliloti and regulating flagellar and transporter genes in CLas. Among the 39 putative RemLas-regulated genes in CLas, 16 contain Rem binding motif, including 10 genes involved in flagellar assembly. Taken together, this study offers valuable insights regarding regulatory genes of CLas with many of them involved in regulating motility and oxidative stress response. The regulation of flagellar genes by Rem in CLas unravels critical information regarding motility in CLas infection of hosts.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143075225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Loop-Mediated Isothermal Amplification Detection of Phytophthora kernoviae, P. ramorum, and the P. ramorum NA1 Lineage on a Microfluidic Chip and Smartphone Platform. 在微流控芯片和智能手机平台上进行环介导等温扩增检测噬菌体（Phytophthora kernoviae）、根瘤蚜（Phytophthora ramorum）和根瘤蚜 NA1 系。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-01-27 DOI: 10.1094/PHYTO-02-24-0055-R

Amanda Mainello-Land, Amanda C Saville, Jyotsna Acharya, Jean Ristaino

{"title":"Loop-Mediated Isothermal Amplification Detection of Phytophthora kernoviae, P. ramorum, and the P. ramorum NA1 Lineage on a Microfluidic Chip and Smartphone Platform.","authors":"Amanda Mainello-Land, Amanda C Saville, Jyotsna Acharya, Jean Ristaino","doi":"10.1094/PHYTO-02-24-0055-R","DOIUrl":"10.1094/PHYTO-02-24-0055-R","url":null,"abstract":"Rapid, field-deployable assays such as loop-mediated isothermal amplification (LAMP) are critical for detecting nursery and forest pathogens such as Phytophthora ramorum and P. kernoviae to prevent pathogen spread. We developed and validated four LAMP assays for genus-level detection of Phytophthora spp., species-level detection of P. kernoviae and P. ramorum, and lineage-level detection of the P. ramorum NA1 lineage. The cross-reactivity of the two species-specific LAMP assays was evaluated using a set of 18 Phytophthora spp. known to infect nursery crop hosts. The correct target species were detected by the species-level LAMP assays. The Phytophthora spp. LAMP assay was evaluated against 27 Phytophthora spp. and other bacterial and fungal pathogens and reacted with all the Phytophthora spp. evaluated but no other bacterial or fungal species. The limit of detection (LOD) of the P. kernoviae LAMP was 100 fg/µl, and the LOD of the P. ramorum LAMP assay was 1 pg/µl of DNA. The NA1 LAMP assay was tested against the NA1, NA2, EU1, and EU2 lineages of P. ramorum and was lineage-specific but had a higher LOD (100 pg/µl) than the species-specific LAMP assays. Both P. ramorum and P. kernoviae LAMP assays were highly precise (>0.94) in detecting the respective pathogens in symptomatic rhododendron leaves and co-inoculation experiments. The four LAMP assays were run in tandem on a microfluidic chip and smartphone platform and can be used in the field to detect and monitor spread of these regulatory Phytophthora spp. in forest and/or nursery settings.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"192-203"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142472981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Microbial Metabolite Wuyiencin Potentially Targets Threonine Dehydratase in Didymella segeticola to Achieve Control of Tea Leaf Spot. 微生物代谢物武夷菌素能潜在地靶向半知菌（Didymella segeticola）体内的苏氨酸脱水酶，从而达到防治茶叶斑点病的目的。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-02-24 DOI: 10.1094/PHYTO-06-24-0200-R

Youli Ma, Peiying Li, Wenjing Xie, Fenghua Liu, Dongxue Li, Atta Ur Rehman, Delu Wang, Jing-Jiang Zhou, Yue Ma, Zhuo Chen

{"title":"The Microbial Metabolite Wuyiencin Potentially Targets Threonine Dehydratase in Didymella segeticola to Achieve Control of Tea Leaf Spot.","authors":"Youli Ma, Peiying Li, Wenjing Xie, Fenghua Liu, Dongxue Li, Atta Ur Rehman, Delu Wang, Jing-Jiang Zhou, Yue Ma, Zhuo Chen","doi":"10.1094/PHYTO-06-24-0200-R","DOIUrl":"10.1094/PHYTO-06-24-0200-R","url":null,"abstract":"Tea leaf spot caused by Didymella segeticola is a disease that has recently been discovered in the tea plantations of Southwest China and that has a significant negative impact on the yield and quality of tea leaves. Wuyiencin is a nucleotide antimicrobial that is effective against a range of fungal diseases. However, its mode of action is still unclear. The current study found that wuyiencin inhibited the mycelial growth of D. segeticola in vitro. Meanwhile, in vivo experiments confirmed that wuyiencin had a significant curative effect on tea leaf spot. Microscopic observation indicated that it damaged the organelles and nucleus in fungal cells. Reverse transcription quantitative PCR assays revealed that mycelium treated with wuyiencin at the half-maximal effective concentration (EC50) dosage for 1 h exhibited 3.23 times lower expression of threonine dehydratase (td) gene, which is responsible for producing pyruvate. The wild-type (WT) strain had a 1.77-fold higher pyruvate concentration than that in the td mutant (P < 0.05). The td mutant was more sensitive than the WT to wuyiencin treatment, with the EC50 value in the td mutant being 30.01 μg/ml compared with 82.34 μg/ml in the WT. Molecular docking demonstrated that wuyiencin bound to td, with a binding energy of -10.47 kcal/mol. Compared with the WT strain, wuyiencin significantly reduced ATP concentration of the td mutant strain at dosages of 80.0 and 160.0 µg/ml. In total, wuyiencin reduced td activity, inhibited pyruvate production, and decreased ATP content in the phytopathogenic fungus, ultimately disturbing the growth of the mycelium.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"151-161"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142506496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multicomponent Resistance Responses of Melon to Zucchini Yellow Mosaic Virus. 甜瓜对西葫芦黄镶嵌病毒的多成分抗性反应。

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-02-01 Epub Date: 2025-02-06 DOI: 10.1094/PHYTO-05-24-0166-R

Líllian B J Bibiano, Camila P Carvalho, Ricardo Giória, Jorge A M Rezende, Luis E A Camargo

{"title":"Multicomponent Resistance Responses of Melon to Zucchini Yellow Mosaic Virus.","authors":"Líllian B J Bibiano, Camila P Carvalho, Ricardo Giória, Jorge A M Rezende, Luis E A Camargo","doi":"10.1094/PHYTO-05-24-0166-R","DOIUrl":"10.1094/PHYTO-05-24-0166-R","url":null,"abstract":"A major resistance gene of the melon accession PI414723 to zucchini yellow mosaic virus (ZYMV) is located at the Zym-1 locus on chromosome 2, but the underlying defense mechanisms are poorly understood. The physiological responses and expression of selected genes at Zym-1 were assessed in PI414723 and in the susceptible genotype Védrantais. Viral titers and the expression of genes related to systemic acquired resistance were evaluated in inoculated (Inoc) and noninoculated (Non-Inoc) portions of the cotyledons at 3, 7, and 10 days after inoculation and in apical leaves at 10 days after inoculation. ZYMV was detected in both portions of the cotyledons but not in the apical leaves of PI414723 plants. Also, ZYMV was recovered in a susceptible zucchini only from Inoc portions at 3 days after inoculation. By contrast, in Védrantais, ZYMV was detected and recovered from all tissues at high concentrations. Starchy local lesions and accumulation of transcripts of the systemic acquired resistance marker genes PR1 and PR4 were also detected in the resistant genotype. Plus, transcripts of one candidate resistance gene analog previously located at Zym-1 and of two melon homologs of restricted tobacco etch virus movement 2 genes located close to Zym-1 accumulated only in PI414723. It is proposed that resistance results from the combined action of the R gene involved in restricting ZYMV replication after a supposed recognition event and of the restricted tobacco etch virus movement genes that impact viral systemic movement to distal apical tissues.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"162-171"},"PeriodicalIF":2.6,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142522711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dispersal of Colletotrichum acutatum Sensu Lato Conidia from Infected Citrus and Strawberry Under Simulated Rainfall and Different Laminar and Turbulent Wind Speeds.

IF 2.6 2区农林科学

Phytopathology Pub Date : 2025-01-29 DOI: 10.1094/PHYTO-11-24-0342-R

Andre B Gama, Maria Cândida de Godoy Gasparoto, Gavin H Poole, Clive H Bock, Timothy R Gottwald, Lilian Amorim, Natalia A Peres, Megan M Dewdney

{"title":"Dispersal of Colletotrichum acutatum Sensu Lato Conidia from Infected Citrus and Strawberry Under Simulated Rainfall and Different Laminar and Turbulent Wind Speeds.","authors":"Andre B Gama, Maria Cândida de Godoy Gasparoto, Gavin H Poole, Clive H Bock, Timothy R Gottwald, Lilian Amorim, Natalia A Peres, Megan M Dewdney","doi":"10.1094/PHYTO-11-24-0342-R","DOIUrl":"https://doi.org/10.1094/PHYTO-11-24-0342-R","url":null,"abstract":"Species of the Colletotrichum acutatum complex cause postbloom fruit drop of citrus and anthracnose fruit rot of strawberries. C. acutatum produces acervuli in diseased citrus flowers and strawberry fruit, surviving asymptomatically on vegetative tissues. Previous studies have suggested that dispersal mechanisms other than windblown rain may be involved in dispersal of conidia of C. acutatum sensu lato. Our hypothesis is that wind alone may play a role in dispersal, especially for inoculum surviving on vegetative tissue. Our objectives were to study the dispersal pattern of C. acutatum sensu lato from strawberry fruit and leaves, and citrus flowers and leaves by placing semi-selective media at known distances away from inoculum sources in laminar flow and turbulent wind tunnels. The number of C. acutatum sensu lato colony-forming units (CFU) on each plate was correlated to the distance from inoculum sources. Conidia were dispersed up to 15 meters in wind speeds greater than 10 meters per second but observed dispersal patterns were not described by the models we tested. A negative exponential model adequately described the dispersal gradient of inoculum downwind, particularly for the dispersal gradient in turbulent wind. Dispersal in rain splash and wind was limited to short distances. Our data describes how conidia spread from inoculum sources, and for the first time describes how dispersal of C. acutatum sensu lato secondary conidia occurs from citrus and strawberry leaves. Knowledge of the dispersal of conidia of C. acutatum sensu lato can provide valuable information on epidemic development, and thus approaches for disease management.","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143067649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0