Australasian Plant Pathology最新文献

{"title":"Identification and molecular characterization of a novel Betacytorhabdovirus detected in citrus trees affected by quick decline in Southern Iran","authors":"Ali Abbasi,&nbsp;Abozar Ghorbani,&nbsp;Mahsa Rostami,&nbsp;Laleh Ilkhan","doi":"10.1007/s13313-026-01172-4","DOIUrl":"10.1007/s13313-026-01172-4","url":null,"abstract":"<div><p>Citrus quick decline (CQD) is an emerging disorder threatening citrus orchards in southern Iran. The disease causes rapid wilting, leaf desiccation, and death of trees within weeks, leading to significant yield losses. Despite extensive surveys, no known pathogen had been consistently associated with this syndrome. Using next-generation sequencing (NGS), a novel betacytorhabdovirus, tentatively named citrus quick decline-associated virus (CQDaV), was identified in citrus trees showing decline symptoms in Kerman Province. The viral genome displayed the canonical betacytorhabdovirus genome organization (3′-N-P-P3-M-G-L-5′). Phylogenetic analysis based on the complete L protein sequence placed the virus within the genus <i>Betacytorhabdovirus</i>, with Glycyrrhiza betacytorhabdovirus 1 as its closest recognized relative. The presence of CQDaV was confirmed by reverse transcription quantitative PCR in some symptomatic trees but was absent in healthy controls. This study reports the molecular characterization of a novel betacytorhabdovirus infecting citrus, which was found to be associated with symptomatic trees showing rapid decline in southern Iran.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148613962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a qPCR assay for the rapid detection of the avocado scab fungus Elsinoe perseae","authors":"Nga T. Tran,&nbsp;Louisamarie E. Parkinson,&nbsp;Lara-Simone Pretorius,&nbsp;Romina Gazis,&nbsp;Lederson Gañán-Betancur,&nbsp;Samuel Garty,&nbsp;Andrew D. W. Geering","doi":"10.1007/s13313-026-01169-z","DOIUrl":"10.1007/s13313-026-01169-z","url":null,"abstract":"<div><p><i>Elsinoe perseae</i>, the causal agent of avocado scab disease, is a high-priority biosecurity threat to the Australian avocado industry. Symptom-based diagnosis is unreliable, and morphological identification is hindered by the slow growth of <i>Elsinoe</i> species on artificial media and the absence of a sexual reproductive stage in the field and in axenic culture. Consequently, a rapid and reliable molecular diagnostic tool capable of detecting the pathogen directly from infected fruit or leaf tissue is essential. In this study, we developed a quantitative PCR (qPCR) assay targeting two genomic regions: the internal transcribed spacer 1 (ITS1) region of the rDNA and the RNA polymerase II subunit B (<i>rpb2</i>) gene. The assay can be applied in either singleplex or duplex formats. Both the ITS- and <i>rpb2</i>-targeted assays consistently detected <i>E. perseae</i> DNA from pure cultures. However, detection in infected avocado leaf and fruit tissues was primarily driven by the ITS assay, whereas the <i>rpb2</i> assay exhibited reduced sensitivity, likely reflecting differences in copy number between multicopy rDNA regions and the single-copy <i>rpb2</i> gene. No cross-reactivity was observed against other <i>Elsinoe</i> species or common fungal pathogens of avocado. High analytical sensitivity was achieved, with reliable detection of both targets at concentrations of 10³ copies/µL of synthetic gBlocks dsDNA and 0.1 ng/µL of genomic DNA, using a conservative threshold of Ct ≤ 30. Assay performance was unaffected by minor variations in qPCR reagents and instrument platforms. This assay provides a rapid, sensitive, and highly specific diagnostic tool for biosecurity applications, supporting accurate detection, surveillance, and early response to potential incursions of <i>E. perseae.</i></p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13313-026-01169-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biocontrol and growth-promoting potential of Bacillus subtilis against root-rot disease in sugar beet","authors":"Kamal A. M. Abo-Elyousr,&nbsp;Mansour M. El-Fawy,&nbsp;Esmat F. Ali,&nbsp;Abeer S. Alqurashi,&nbsp;Alaa Baazeem,&nbsp;Mohamed M. Hassan,&nbsp;Roqayah H. Kadi,&nbsp;Nashwa M. A. Sallam","doi":"10.1007/s13313-026-01170-6","DOIUrl":"10.1007/s13313-026-01170-6","url":null,"abstract":"<div><p>Among the various pathogens that cause sugar beet root rot, <i>Rhizoctonia solani</i> is one of the most destructive species globally. This pathogen causes damping-off and root rot during field growth and storage, leading to crop yield losses; therefore, the development of environmentally friendly prevention and control strategies targeting this organism is urgently needed. This study aimed to evaluate, through laboratory and greenhouse experiments, the biological control potential of <i>Bacillus subtilis</i> against the sugar beet root rot pathogen <i>R. solani</i>, and to investigate their plant growth-promoting properties. Pathogenicity tests revealed that all tested fungal isolates were capable of infecting sugar beet plants and causing root rot symptoms. Among them, isolate KA 3 showed the highest percentage of damping-off and root rot severity. Therefore, the most aggressive isolate was selected for subsequent antagonistic and greenhouse experiments. This study employed the dual culture method for in vitro screening. The 15 <i>Bacillus</i> strains isolated from the sugar beet rhizosphere exhibited varying levels of antagonistic activity. Among them, <i>B. subtilis</i> strain K 2 had the strongest activity, with a mycelia inhibition rate of 62.51% against <i>R. solani</i>. Under greenhouse conditions, <i>B. subtilis</i> isolate K2 reduced disease severity from 95.5% in the infected control to 22.4%, corresponding to 76.5% disease suppression, while isolate K5 reduced disease severity to 32.3% (66.2% suppression). In addition, treatment with <i>B. subtilis</i> can significantly promote the growth of infected plants, increasing fresh, dry, root, and root dry weight of sugar beet plants. Furthermore, <i>B. subtilis</i> treatment significantly increased total phenolic and flavonoid contents in sugar beet plants. This study proposes that <i>Bacillus subtilis</i> is a promising biocontrol agent and plant growth promoter, which can be incorporated into integrated disease management (IDM) programs for the sustainable prevention and control of sugar beet root rot.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morpho-Molecular Identification and Race Detection of Xanthomonas campestris pv. campestris Causing Black Rot Disease of Cabbage in Bangladesh","authors":"Arnab Goswami,&nbsp;Nafisa Akter Sadia,&nbsp;Pijush Kanti Jhan,&nbsp;Mahmudul Hasan,&nbsp;Tofazzal Islam,&nbsp;Ujjal Kumar Nath,&nbsp;Jong-In Park,&nbsp;Mehede Hassan Rubel","doi":"10.1007/s13313-026-01171-5","DOIUrl":"10.1007/s13313-026-01171-5","url":null,"abstract":"<div><p>Black rot disease, caused by the seed-borne bacterial pathogen <i>Xanthomonas campestris </i>pv.<i> campestris</i> (<i>Xcc</i>), reduces cabbage yield, featuring V-shaped chlorotic lesions along leaf margins. In December 2024, typical black rot symptoms were observed on cabbage plants in Churamonkathi Union, Jessore District, Bangladesh. Bacteria isolated from symptomatic leaf tissues on King’s medium B base agar were consistent with <i>Xcc</i> based on morphological and biochemical characteristics. Pathogenicity was confirmed by Koch’s postulates, with characteristic symptoms reproduced on healthy cabbage plants 7–14 days after inoculation (DAI). These pathogenic isolates were consolidated as <i>Xcc</i> by <i>Xcc</i>-specific primers (<i>Xcc</i>_53F/R). Subsequently, race determination using race-specific primers revealed that all pathogenic isolates belonged to race 1, as the primer pair <i>Xcc</i>_R2_89.2 F/R produced a 1523 bp amplicon. Partial 16S rRNA gene sequencing of one representative isolate and phylogenetic analysis confirmed its identity as <i>Xcc</i>. This study provides the morpho-molecular confirmation and race detection of <i>Xcc</i> race 1 causing black rot on cabbage in Bangladesh, where the pathogen was previously reported only from mustard seeds without detailed characterization. The findings will facilitate the development of effective disease management strategies for sustainable cabbage production in the country.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of immature fruit rot of jackfruit (Artocarpus heterophyllus Lam.) caused by Rhizopus arrhizus in China","authors":"Tanvir Ahmad,&nbsp;Yang Liu","doi":"10.1007/s13313-026-01168-0","DOIUrl":"10.1007/s13313-026-01168-0","url":null,"abstract":"","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148465694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of Colletotrichum siamense causing leaf spot disease on white Palas climber (Spatholobus parviflorus) in India","authors":"Namitha Udayakumar,&nbsp;Shambhu Kumar,&nbsp;Kalathil Thodi Mufeeda,&nbsp;S. Surya,&nbsp;Shivannegowda Mahadevakumar,&nbsp;Raghvendra Singh","doi":"10.1007/s13313-026-01167-1","DOIUrl":"10.1007/s13313-026-01167-1","url":null,"abstract":"","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148466036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated control of peach powdery mildew using green pruning and fungicides in Iran","authors":"Naser Amanifar","doi":"10.1007/s13313-026-01166-2","DOIUrl":"10.1007/s13313-026-01166-2","url":null,"abstract":"<div><p>Peach powdery mildew caused by <i>Podosphaera pannosa</i> (Wallr.: Fr.) de Bary (syn. <i>Sphaerotheca pannosa</i>) is a major fungal disease in peach orchards of Iran. During the 2023–2024 growing seasons, a commercial orchard planted with the local cultivar ‘Zafarani’, with a history of severe powdery mildew infection, located in the Zayandeh Rood region, was selected to evaluate the integrated effects of green pruning and fungicide applications on disease management. Two fungicide mixtures were tested: pydiflumetofen + difenoconazole (Miravis Duo^® SC, 20%), applied at 0.0002 (2 ml/10 L), and kresoxim-methyl + boscalid (Collis^® SC, 20/10%), applied at 0.0003 (3 ml/10 L), respectively. The experiment was arranged as a randomized complete block design with six treatments and five replicates, including an untreated control, green pruning alone, individual fungicide applications, and combined fungicide and green pruning treatments. Fungicides were applied five weeks after full petal fall, while green pruning in the combined treatments was performed one day prior to fungicide application. The treatments significantly affected disease incidence and severity on both leaves and fruits (P ≤ 0.01). The highest disease incidence was recorded in the untreated control (71.6%), whereas the lowest incidence was observed in Miravis Duo^® combined with green pruning (1.8% on leaves and 0.4% on fruits). Fruit disease severity in the combined treatment (Miravis Duo^® application plus green pruning) was significantly reduced to less than 0.005, compared to approximately 1.7 in the control group. The integrated use of green pruning and Miravis Duo^® demonstrated a statistically supported synergistic effect. The interaction term in the two-way ANOVA (fungicide × green pruning) was significant (p &lt; 0.01), confirming that the combined treatment produced a greater reduction in disease severity than either factor alone. Under field conditions in the Zayandeh Rood region, this combined strategy reduced fruit disease severity to &lt; 0.005, compared with 1.7 in the untreated control, corresponding to an approximately 99% reduction in disease incidence.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148380829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of fungicides and biological controls as pruning wound protectants for trunk disease pathogens of almond in Australia","authors":"Brittany J. Oswald,&nbsp;Suzanne F. McKay,&nbsp;Tarita Furlan,&nbsp;Mark R. Sosnowski","doi":"10.1007/s13313-026-01162-6","DOIUrl":"10.1007/s13313-026-01162-6","url":null,"abstract":"<div><p>Almond trunk diseases can cause a significant decline in orchard productivity and profitability through limb and tree death. Several pathogens have been implicated in the trunk disease complex in Australia, with <i>Diplodia seriata</i> reported as most prominent. These pathogens can infect through wounds, such as those created during pruning or other mechanical processes. Fungicide and biological products are registered for managing these diseases in California, but there is only one wound dressing product registered for trunk diseases in Australia. In three in vitro experiments, 21 treatments, including fungicides and biological controls, were evaluated for the inhibition of mycelial growth of five trunk disease pathogens: <i>Colletotrichum acutatum</i><i>, </i><i>Collophora rubra</i><i>, </i><i>Diplodia seriata</i><i>, </i><i>Eutypa lata</i> and <i>Pleurostoma richardsiae</i>. Most treatments reduced mycelial growth of most pathogens by 50–100%. Based on in vitro trial results, nine wound treatments were selected for evaluation in two field trials against <i>D. seriata</i>, with four treatments; fluopyram &amp; tebuconazole, azoxystrobin &amp; tebuconazole, fluazinam and pyraclostrobin &amp; fluxapyroxad, providing 41–87% disease control<i>.</i></p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148381016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification, biological characteristics and synergistic fungicide screening against Alternaria burnsii causing sorghum leaf spot","authors":"Zhuangzhuang Li,&nbsp;Wei Jia,&nbsp;Haiming Duan,&nbsp;Shengyu Yang,&nbsp;Xingyu Liu,&nbsp;Xinyu He,&nbsp;Yuxun Hua,&nbsp;Qinghua Jiang","doi":"10.1007/s13313-026-01164-4","DOIUrl":"10.1007/s13313-026-01164-4","url":null,"abstract":"<div><p>The leaf spot poses a growing threat to sorghum health. The screening isolate GL-2 was identified as <i>Alternaria burnsii</i>. Among the tested fungicides, fludioxonil exhibited the highest potency, with a median effective concentration (EC₅₀) of 0.16 mg L^− 1. Two combinations showed synergistic effects: pyraclostrobin: flusilazole at a ratio of 0.60:1 (synergy ratio, SR = 1.75) and fludioxonil: procymidone at 0.28:1 (SR = 1.58). The latter combination demonstrated the most effective disease suppression, achieving 83.61% inhibition on detached leaves and 89.87% control efficacy in vivo. Mechanistic analysis revealed that the fludioxonil: procymidone blend primarily disrupts pathogen cell membrane integrity, leading to increased electrical conductivity. Furthermore, this treatment interfered with stress-related metabolic pathways in the pathogen, resulting in notable alterations in antioxidant enzyme activities, soluble protein content, and reducing sugar levels. These findings elucidate the practical effectiveness and physiological impacts of fungicidal combinations, offering valuable insights for enhancing sorghum leaf spot management strategies.</p></div>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complete genome sequence of watermelon silver mottle virus infecting Momordica charantia L. in China","authors":"Zhongshan Chen,&nbsp;Enhui Li,&nbsp;Lele Cai,&nbsp;Duanxiang Xu,&nbsp;Wenli Du,&nbsp;Xiaolin Zeng,&nbsp;Fangluan Gao,&nbsp;Shan Gao","doi":"10.1007/s13313-026-01165-3","DOIUrl":"10.1007/s13313-026-01165-3","url":null,"abstract":"<p>We report the first identification and complete genome sequence of a watermelon silver mottle virus (WSMoV) isolate, designated WSMoV-MC, infecting bitter gourd (<i>Momordica charantia</i> L.) from Fujian Province, China. The tripartite genome, comprising large (L, 8,914 nt), medium (M, 4,872 nt), and small (S, 3,555 nt) RNA segments, encodes five typical tospoviral proteins. Sequence analysis revealed that WSMoV-MC shares the highest nucleotide identity (&gt; 99%) with the GL-1 isolate from <i>Siraitia grosvenorii</i>. Phylogenetic analysis based on the nucleocapsid (<i>N</i>) gene assigned WSMoV-MC to lineage 2, clustering with other Chinese isolates. Furthermore, a significant reassortment event was detected at the L-M junction, with the GZ isolate (accession no. JX177647) identified as a potential donor. This report expands the known host range of WSMoV and provides essential genomic data for monitoring its molecular evolution in cucurbit crops.</p>","PeriodicalId":8598,"journal":{"name":"Australasian Plant Pathology","volume":"55 4","pages":""},"PeriodicalIF":1.2,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}