First Report of Red Rot of Jujube Fruit Caused by Botryosphaeria dothidea in China

HomePlant DiseaseVol. 102, No. 7First Report of Red Rot of Jujube Fruit Caused by Botryosphaeria dothidea in China PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Red Rot of Jujube Fruit Caused by Botryosphaeria dothidea in ChinaL. X. Ran, M. Zhang, and H. M. ShenL. X. Ran, M. Zhang, and H. M. Shen†Corresponding author: H. M. Shen; E-mail: E-mail Address: [email protected]http://orcid.org/0000-0001-9060-3734AffiliationsAuthors and Affiliations L. X. Ran , College of Forestry, Hebei Agricultural University, and Hebei Provincial Key Laboratory of Forest Germplasm Resources and Protection, Baoding, 071001, P. R. China M. Zhang H. M. Shen † , College of Forestry, Hebei Agricultural University, Baoding, 071001, P.R. China. Published Online:17 May 2018https://doi.org/10.1094/PDIS-07-17-1062-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Jujube (Zizyphus jujuba Mill.) is an economically important fruit tree widely grown in China and South Korea. Jujube fruit has been commonly used in cooking, wine, and traditional medicine for thousands of years. In recent years, red rot disease has seriously affected the growth and quality of gray jujube fruits (Z. jujuba Mill. var. Huizao) in Xinzheng at 34°16′ to 39′ N and 113°30′ to 54′ E, Henan Province, China. Initial symptoms consisted of small, circular, red spots lacking concentric rings that expanded rapidly, and usually within 2 to 3 days, superficial lesions evolved into soft rot affecting the entire fruit, producing a vinasse flavor. The pathogen was isolated from diseased fruits that were surface disinfected with 70% ethanol for 30 s, followed by 0.1% HgCl2 for 1 min and rinsed three times in sterile distilled water. Then the skin on the margins of healthy and infected tissue was aseptically peeled off with a scalpel, cut into 3- to 4-mm cubes, placed on water agar, and incubated at 25°C in the dark. Once fungal growth was evident, agar disks with hyphal tips were transferred to potato dextrose agar (PDA) plates and incubated at 25°C in the dark for purification. All fungal colonies were spread over Petri dishes of PDA, and after an overnight incubation, single germinating conidium was transferred to fresh PDA. The pure culture obtained was subjected to morphological characterization. The aerial mycelium was initially white, turning dark gray after 5 to 6 days and black 2 weeks later. The mycelium grew luxuriantly with a velvet appearance. The pycnidia were flask-shaped and averaged 196.9 μm high and 213.3 μm wide. Conidia were hyaline, unicellular, fusoid, and averaged 15.0 to 20.0 × 4.5 to 6.5 μm. These morphological characteristics are similar to those reported by Slippers et al. (2004). To confirm the identity of the fungus, the internal transcribed spacer (ITS) region and partial translation elongation factor 1-alpha (EF1-α) gene were partially sequenced using primers ITS1/ITS4 and EF1-728F/EF1-986R (De Wet et al. 2008). The obtained ITS sequence (GenBank MG827237) and EF1-α sequence (MG850862) showed 99% identity with those of the reference sequences of Botryosphaeria dothidea (AJ938004 and JX462293, respectively). Morphological and molecular results confirmed the fungus as B. dothidea. Pathogenicity of the isolated fungus was evaluated by inoculation of 20 surface-sterilized, detached gray jujube fruits, and the same number of fresh fruits of gray jujube on a healthy tree, with mycelial PDA plugs (5 mm in diameter) placed on both wounded and nonwounded jujube fruits. As a control, wounded and nonwounded fruits were inoculated with sterile PDA plugs. Detached fruits were incubated in plastic boxes under 90% RH at 25°C, and rot symptoms developed on wounded and unwounded inoculated fruits 3 days after incubation, while control fruits remained symptomless. All branches with inoculated fruits were enclosed in a clear plastic bag to maintain humidity and prevent cross contamination. Symptoms similar to the original ones on naturally infected fruits were observed on all wound-inoculated fruits 3 days after inoculation, while no symptoms developed on unwounded inoculated fruits or controls. The same fungus was reisolated from each of the inoculated fruits with symptoms, fulfilling Koch's postulates, whereas no fungus could be isolated from asymptomatic and control fruits. Based on the results of both morphological and molecular identification, the pathogen of red rot of gray jujube fruits in Xinzheng was identified as B. dothidea (Moug. ex Fr.) Ces. et de Not., which is different from Xanthomonas arboricola, the pathogen causing bacterial fruit rot of jujube in Korea (Myung et al. 2010), and Fusarium oxysporum, which had been reported to cause soft fruit rot disease of gray jujube (Zhang et al. 2013). To our knowledge, this is the first report of B. dothidea causing red rot of gray jujube fruits in China.References:De Wet, J., et al. 2008. Mol. Phylogenet. Evol. 46:116. https://doi.org/10.1016/j.ympev.2007.08.016 Crossref, ISI, Google ScholarMyung, I. S., et al. 2010. New Dis. Rep. 22:276. Google ScholarSlippers, B., et al. 2004. Mycologia 96:83. https://doi.org/10.1080/15572536.2005.11833000 Crossref, ISI, Google ScholarZhang, M., et al. 2013. Plant Dis. 97:1509. https://doi.org/10.1094/PDIS-04-13-0379-PDN Link, ISI, Google ScholarFunding: Natural Science Foundation of Hebei Province (C2016204202).DetailsFiguresLiterature CitedRelated Vol. 102, No. 7 July 2018SubscribeISSN:0191-2917e-ISSN:1943-7692 Metrics Article History Issue Date: 27 Jun 2018Published: 17 May 2018First Look: 7 Feb 2018Accepted: 5 Feb 2018 Page: 1458 Information© 2018 The American Phytopathological SocietyFundingNatural Science Foundation of Hebei ProvinceGrant/Award Number: C2016204202Cited byDiversity and Pathogenicity of Fungi Associated with Fruit Rot of Winter Jujube in Shandong Province, ChinaXi Xu, Lifeng Guo, Chunbo Yang, Haolin Teng, Guijin Shen, Shuo Wang, Junlei Zhao, Xilang Yang, Li Zhang, Xiangjing Wang, Junwei Zhao, and Wensheng Xiang3 March 2023 | Plant Disease, Vol. 0, No. 0Botryosphaeria dothidea (canker of almond)CABI Compendium, Vol. CABI CompendiumThe full-length genome sequence of a novel mitovirus from Botryosphaeria dothidea, the causal agent of pear ring rot disease2 August 2021 | Archives of Virology, Vol. 166, No. 10A novel mycovirus isolated from the plant-pathogenic fungus Botryosphaeria dothidea17 February 2021 | Archives of Virology, Vol. 47Molecular characterization of a novel mitovirus from the plant‑pathogenic fungus Botryosphaeria dothidea22 November 2020 | Archives of Virology, Vol. 166, No. 2Bioprospecting for secondary metabolites of family Botryosphaeriaceae from a biotechnological perspective