@ARTICLE{TreeBASE2Ref24095, author = {André Wilson Campos Rosado and Alexandre Reis Machado and Olinto Liparini Pereira}, title = {First Report of Pestalotiopsis adusta Causing Postharvest Rot Disease on Immature Coconut in Brazil}, year = {2015}, keywords = {}, doi = {}, url = {http://}, pmid = {}, journal = {Plant Disease}, volume = {}, number = {}, pages = {}, abstract = {Cocos nucifera L. is one of the most important perennial tropical crops (Huang 2013). In August 2012, immature coconuts showing external and internal symptoms of rot were collected from a local market in Viçosa, Minas Gerais state, Brazil. The initial symptoms of infection were characterized by a straw-colored lesion in the shell near the peduncle. The lesions in the fruit rind showed dark points corresponding to the acervuli of the fungus. The rot progressed to the entire fruit, including the endosperm, making the coconut water unsuitable for consumption. Direct isolation was performed from a naturally infected coconut; a single-spore culture was obtained and deposited in the culture collection ?Coleção Octávio Almeida Drummond? of the Universidade Federal de Viçosa (Accession Nº COAD 1781). White-colored colonies appeared on potato dextrose agar after 7 days of incubation at 25º C. The colonies produced numerous black spore masses. The underside of the culture was yellowish. Thirty measurements of the relevant morphological characteristics were made using a light microscope. The conidiomata are acervular, subepidermal and with basal stroma. The conidiogenous cells are discrete, short and filiform. The conidia measured 20 to 22 × 5 to 6 µm, with dark median cells. The apical and basal cells were hyaline, fusiform to ellipsoid, with four transverse septa, two apical appendages 5 to 7 µm long and a filiform basal appendage. DNA was extracted using the WizardTM Genomic DNA Purification Kit (Promega Corporation). The gene regions ?-tubulin (?t), Internal Transcribed Spacers regions 1 and 2 including the 5.8S rRNA (ITS), and Translation Elongation Factor 1-? (TEF1-?) effectively distinguish Pestalotiopsis species (Sajeewa 2012). Target sequences of these regions were amplified using primers T1 and 2b, ITS1 and ITS4, and 983F and 2218R, respectively. The amplicons were purified and sequenced by Macrogen, Korea. The sequences obtained were deposited in GenBank (Accessions Nº KP308540, KP308461, KP308539). Bayesian inference analyses were performed with the CIPRES web portal using MrBayes v. 3.2.3 (Miller 2010). The resulting alignment was deposited into TreeBASE (Study xx). Based on the morphological and phylogenetic analyses, the fungus was identified as Pestalotiopsis adusta (Ellis & Everhart) Steyaert. The isolate was tested for pathogenicity using six immature coconuts without visible symptoms of disease. Three fragments of the regions near the bracts were removed, and a 6-mm diameter disk containing mycelia was placed over the wound. As a control, PDA plugs were placed on the wounded surfaces. The inoculated fruits were incubated at 28 °C and kept in a moist chamber for 48 h. After 7 days, symptoms were observed in inoculated fruits but not in the controls. It was possible to reisolate the inoculated fungus from diseased tissues, fulfilling Koch?s postulates and showing that P. adusta is pathogenic to coconut. To our knowledge, this is the first report of Pestalotiopsis adusta causing postharvest rot disease on immature coconut in Brazil. These findings may be helpful for further studies on quarantine programs and management measures.} }

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