Paper presented at the 52nd CFCS Annual Meeting, Guadeloupe, July 10-16, 2016 Most recently, the potexvirus, Cactus Virus X causing chlorosis, speckling and mottling on stems (Fig. 1C), and Cladosporium cladosporioides causing sooty mold on fruit (Fig. 1F) have been issues for commercial production and dooryard plantings. Sooty mold is not a plant pathogen but grow on surfaces where honeydew deposits accumulate. Honeydew is a sweet, sticky liquid that plant-sucking insects excrete as they ingest large quantities of sap from a plant. With the increase of pitaya production in south Florida cphad been increased during the last year and this provides new pathogens to stablished in the area. Therefore, it is required an effective disease management strategy for all these diseases since very few fungicides are currently labeled for use on pitaya in Florida and these diseases has been a serious issue for pitaya growers in south Florida (Palmateer et al., 2007, Tarnowski et al., 2010, Sanahuja et al., 2016). References Alfieri Jr., S.A., Langdon, K.R., Wehlburg, C., and Kimbrough, J.W. 1984. Index of Plant Diseases in Florida (Revised). Florida Dept. Agric. and Consumer Serv., Div. Plant Ind. Bull. 11: 1-389. Bailey, J.A. and Jeger, M.J. 1992. Colletotrichum: Biology, Pathology and Control. CAB International, Wallingford, UK. Berbee, M.L., Pirseyedi, M., and Hubbard, S. 1999. Cochliobolus phylogenetics and the origin of known, highly virulent pathogens, inferred from ITS and glyceraldehyde-3-phosphate dehydrogenase gene sequences. Mycologia. 91: 964977. Chuang, M.F., Ni, H.F., Yang, H.R., Hsu, S.L., Lai, S.Y. and Jiang, Y.L. 2012 First report of stem canker disease of pitaya (Hylocereus undatus, H. polyrhizus) caused by Neoscytalidium dimidiatum in Taiwan. Plant Dis 96:906. Crane, J. and Balerdi, C. 2005. Pitaya growing in the Florida home landscape. Horticultural Sciences Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Document HS1068. Available at the EDIS website Crous, P.W., Slippers, B., WingďŹ eld, M.J., Rheeder, J., Marasas, W.F.O., Philips, A.J.L., Alves, A., Burgess, T., Barber, P. and Groenewald, J.Z. (2006) Phylogenetic lineages in the Botryosphaeriaceae. Stud Mycol 55:235– 253. Daire, X., Clair, D., Reinert, W. and Boudon-Padieu, E. 1997. Detection and differentiation of grapevine yellows phytoplasmas belonging to the elm yellows group and to the stolbur subgroup by PCR amplification of non-ribosomal DNA. Eur J Plant Pathol. 103: 507-514. Du, M., Schardl, C.L., Nuckles, E.M. and Vaillancourt, L.J. 2005. Using mating-type gene sequences for improved phylogenetic resolution of Collectotrichum species complexes. Mycologia 97: 641-658. Durbin, R.D., L.H. Davis, and K.F. Baker. 1955. A Helminthosporium stem rot of cacti. Phytopathology. 45: 509-512. Ellis, M.B. 1971. In: Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, England. 1971. Pp: 432. Evans, E.A., Huntley, J., Crane, J. and Wysocki, A.F. 2010. 2010 cost estimates of establishing and producing pitaya (dragon fruit) in south Florida. Food and Resource Economics Department, UF/IFAS Extension. EDIS document FE888. Available at EDIS website at http://edis.ifas.ufl.edu. Kim, Y.H., Jum, O.K., Sung, M.J., Shin, J.S., Kim, J.H. and Jeoung, M.I. 2000. Occurrence of Colletotrichum stem rot caused by Glomerella cingulate on graft-cactus in Korea. J. Plant Pathology. 16: 242-245. Lan, G.-B., and He, Z.-F. 2012. First report of brown spot disease caused by Neoscytalidium dimidiatum on Hylocereus undatus in Guangdong, Chinese Mainland. Plant Dis. 96:1702. Mizrahi, Y.A., Nerd, A. and Nobel, P.S. 1997. Cacti as crops. Hortic. Rev. 18:321-346. Mohd, M.H., Salleh, B. and Zakaria, L. 2013. Identification and molecular characterizations of Neoscytalidium dimidiatum causing stem canker of red-fleshed dragon fruit (Hylocereus polyrhizus) in Malaysia. J. Phytopathol. 161: 841- 849. Palmateer, A.J. and Ploetz, R.C. 2006. Anthracnose of pitahaya: A new disease on a new crop in south Florida. Proc. Fla. State Hort. Soc. 119: 50-51. Palmateer, A.J., Ploetz, R.C., van Santen, E. and Correll, J.C. 2007. First occurrence of Anthracnose caused by Colletotrichum gloeosporioides on pitahaya. Plant Dis. 91: 631. Sanahuja, G., Lopez, P. and Palmateer, A.J. 2016. First report of Neoscytalidium dimidiatum causing stem and fruit canker of Hylocereus undatus in Florida. Plant Dis. http://dx.doi.org/10.1094/PDIS-11-15-1319-PDN. Taba, S., Mikami, D., Takaesu, K., Ooshiro, A., Moromizato, Z., Nakasone, S. and Kawano, S. 2006. Anthracnose of pitaya (Hylocereus undatus) by Colletotrichum gloeosporioides. Jpn. J. Phytopathol. 72: 25-27. Taba, S., Miyahira, N., Nasu, K., Takushi, T. and Moromizato, Z. 2007. Fruit rot of Strawberry pear (pitaya) caused by Bipolaris cactivora. J. Gen. Plant Pathol. 73: 374-376.
20