Abstract. Leaf blight caused by Guignardia endophyllicola is reported for the first time on Cymbidium (Orchidaceae) in Brazil.Hybrids of Cymbidium are among the most important commercial orchids cultivated in Brazil. In June 2006, leaves of an undetermined Cymbidium hybrid showing severe necrotic symptoms were observed in an orchid nursery in Viçosa (State of Minas Gerais, Brazil). Leaf lesions initially were punctiform abaxially becoming circular, coalescing and leading to extensive necrosis. No fungal structures were found on diseased tissues; however, culturing of surface sterilised fragments of such necrotic tissue in V8 juice agar repeatedly resulted in pure dense blackish fungal cultures. These cultures later sporulated in culture and were further examined.The fungus had the following morphology (VIC 30428): pseudothecia intermixed among pycnidia, unilocular, subglobose, solitary or in groups, black, with a stromatic wall composed of several layers of compressed dark brown cells; asci bitunicate ( Fig. 1), subclavate to cylindrical, eightspored; ascospores biseriate, 13-17 × 3-5 μm, one-celled, fusiform-elliptical, broad in middle, hyaline, with a distinct mucilaginous appendages at both ends; pycnidia intermixed among pseudothecia, variable in shape, black, ostiolate; conidia one-celled, hyaline, obovate to pyriform, 9-14 × 5-7 μm, surrounded by a thick mucilaginous coat, with a hyaline apical appendage, 6-12 μm long. The fungus fitted well within the description of Guignardia endophyllicola, a species previously known only as an endophyte of ericaceous plants (Okane et al. 2001). Nevertheless, its anamorph, Phyllosticta capitalensis, is a well-known fungal pathogen of the family Orchidaceae (Cash and Watson 1955;van der Aa and Vanev 2002). Mendes et al. (1998) did not record the occurrence of P. capitalensis in Brazil. However, in this country, P. capitalensis has been previously reported on the orchid genus Stanhopea, host in which the type species was described (Nag Raj 1993;van der Aa and Vanev 2002).Mycelial plugs containing reproductive structures were taken from a 10-day-old culture growing on V8 juice agar and placed on healthy leaves of hybrid Cymbidium. The inoculated leaves were kept inside moistened plastic bags for 2 days and then in a greenhouse at 25 • C. After 7 days, symptoms similar to those previously observed were detected (Fig. 2) and the fungus was reisolated from infected parts. The control leaves, on which V8 juice agar plugs were deposited, remained healthy.

New leaf spot and pseudobulb diseases caused by Phyllosticta capitalensis are reported for the first time on the orchid Bifrenaria harrisoniae.Bifrenaria harrisoniae (Hook.) Rchb. f. is an orchid species with terrestrial habitat, characteristic of the Brazilian 'campos rupestres'. Due to its high ornamental potential, this species has been collected from its natural habitat and in conjunction with the vulnerability of its habitat, in some Brazilian states it is considered to be a threatened species. Recently, this species has been propagated in vitro by some Brazilian orchid growers for commercial purposes. In June 2006, an exploratory project surveying and describing the phytopathogenic and endophytic mycodiversity associated with the family Orchidaceae in the state of Minas Gerais was initiated. In a survey of the campos rupestres of Serra de Ouro Branco (Fig. 1), at Ouro Branco city in Minas Gerais State, Brazil, samples of the orchid B. harrisoniae with severe leaf spotting symptoms were collected (Fig. 2). Spots were initially chlorotic and circular in shape, became necrotic and black with a chlorotic halo, and coalesced to cover the entire width of the leaves, leading to leaf death. Pseudobulbs were also diseased in severely infected plants (Fig. 3).Morphology of the fungus on host tissue included, pycnidia immersed, solitary or aggregated, subepidermal, variable in shape, black, glabrous, with an apical ostiole (Fig. 4); wall stromatic, composed of several layers of dark brown, thick

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Luffa cylindrica (Cucurbitaceae) is an Asian vine widely known as the source of loofah (4). In Brazil (local name bucha), it is cultivated by small scale producers as a cash crop. In January 2012, samples of fruits were collected in three areas in the municipality of Cipotânea, state of Minas Gerais (Brazil) bearing rot symptoms. These had large necrotic areas with a grayish epidermis and slightly sunken tissue. Internally, the fibrous parts were necrosed, darkened, and unmarketable. Isolations by surface sterilization of necrotic tissue with 10% bleach and plating onto potato dextrose agar yielded colonies with consistent morphology. A representative culture was deposited in the culture collection of the Universidade Federal de Viçosa (UFV) as COAD1119. Inoculations of seven healthy-appearing L. cylindrica fruits were performed with culture disks obtained from 4-day-old cultures grown on PDA, which were placed onto two points on the epidermis of each of seven fruits. Each point was either intact or previously injured with a sterile needle. Controls consisted of two fruits treated equally but with tap water agar disks in place of fungal inoculum. Fruits were then placed on trays with water-soaked cotton and the trays were wrapped in plastic bags and left over a bench at room temperature for 2 days. The plastic bags were then removed. After 5 days, necrosis was evident and fungal fruit bodies appeared at points with injury. No symptoms appeared on controls. Isolation from diseased tissue yielded colonies identical to those of the inoculated fungus. A dried sample was deposited in the local herbarium at UFV (VIC 32053). Slides were mounted in lactophenol and observed. The fungus had subepidermal perithecia, globose to subglobose, from 75.5 to 134 μm diam.; asci bitunicate, cylindrical, 8-spored; pseudoparaphyses filiform; ascospores fusoid to ellipsoidal, from 26 to 45 μm long and 8 to 11.5 μm wide, one septate, and hyaline. This morphology is consistent with Stagonosporopsis cucurbitacearum (syn. Didymella bryoniae) (3), a broad spectrum pathogen of cucurbits. Genomic DNA was extracted from the isolate growing in pure culture and ITS and LSU sequences were generated and deposited in GenBank under the accession numbers KC582022 and KC582021, respectively. Sequences were compared in BLASTn with other entries in GenBank, and the closest match for each region were S. cucurbitacearum strain CAP14C and D. bryoniae strain CBS 133.96 (JQ936326 and GU456335) with 100% of nucleotide homology for ITS and 100% of nucleotide homology for LSU. Cercospora citrullina and C. cucurbitae have been reported in Brazil on L. cylindrica and mistakenly indicated as synonyms of D. bryoniae (2). To our knowledge, this is the first valid report of S. cucurbitacearum causing fruit rot of loofah in Brazil and the first time pathogenicity to this host has been demonstrated. Losses due to the disease on the crop were reported to be high by growers and management to be difficult since there are no fungicides registered for this crop in Brazil. References: (1) M. M. Aveskamp et al. Stud. Mycol 65:1, 2010. (2) M. A. S. Mendes and A. F. Urben. Fungos em Plantas no Brasil. Brasília, Brazil: EMBRAPA-SPI. Retrieved from http://pragawall.cenargen.embrapa.br/aiqweb/michtml/micbanco01a.asp , 2012. (3) E. Puithalingam and P. Holliday. CMI Descriptions of Pathogenic Fungi and Bacteria 332:1, 1972. (4) J. W. Purseglove. Tropical Crops – Dicotyledons. Longman Group, London, 1968.

Abstract. A new postharvest disease caused by Cercospora apii is reported for the first time on fruits of Cucurbita maxima.