Identification of Alternaria spp. in orange trees of Golestan and Mazandaran provinces and investigating their virulence on orange cultivars

Document Type : Research Paper

Authors

1 .Sc. Student,Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

2 Associate ProfessorÙˆ Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

3 Assistant Professor, Department of Plant Protection, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran

Abstract

Alternaria brown spot and postharvest black rot of fruit are serious diseases of citrustrees. These diseases are caused by Alternaria spp. and can be economically destructive on susceptible citrus trees. The aim of this study was to identify the pathogenic species of this fungus and to introduce orange cultivars resistant to this disease. For this purpose, samples suspected to Alternaria infection were collected from orchards of Golestan and Mazandaran provinces and were cultured on PDA and PCA media in the laboratory. Then, the fungi were identified according to the morphological key to Alternaria spp. In order to verify the morphological, molecular identification was done using universal primers ITS1, ITS4 and PCR product sequencing. From 45 isolates collected, the identified species were A. alternata (28 isolates), A. dumosa (12 isolates) and A. atra (5 isolates). For investigating pathogenicity of the isolates, 4 orange cultivars including Thomson Navel, Jaffa Sweet, Sanguinelli Blood, and Valencia were used. The pathogenicity test was done by using spore suspension with 105 spores per ml on the leaf, fruit and, seedling. The results revealed that the isolates of these three species showed serious symptoms on the Thomson, Jaffa, and Valencia cultivars. However, the Sanguinelli was relatively resistant in three pathogenicity tests on the leaf, fruit, and the seedling and the mentioned species were not able to create disease symptoms at this cultivar. Thus, Sanguinelli was introduced as a resistant cultivar against Alternaria spp. in orange.

Keywords


  1. Brown, G. E. & McCornack, A. A. (1972). Decay caused by Alternaria citri in Florida citrus fruit. Plant Disease Reporter, 56, 909-912.
  2. Dalkilic, Z., Timmer, L.W. & Gmitter, F. G. (2005). Linkage of an Alternaria disease resistance gene in mandarin hybrids with RAPD fragments. Journal of American Society of Horticulture Science, 130, 191-195.
  3. Ershad, J. (2009). Fungi of Iran. Iranian Research Institute of Plant Protection press, Tehran, Iran.
  4. Eviner, V. T. & Chapin, F. S. (2003). Gopher-plant-fungal interactions affect establishment of an invasive grass. Ecology Journal, 84, 120-128.
  5. Gardner, J. M., Kono. Y. & Chandler, J. L. (1986). Bioassay and hostselectivity of Alternaria citri toxins affecting rough lemon and mandarins. Physiological and Molecular Plant Pathology, 29, 293-304.
  6. Golmohammadi, M. & Rahimian, H. (2004). First report of brown spot caused by Alternaria alternata on tangrine in Iran. In: Proceedings of 16th Iranian plant protection congress, 28 Aug.-1 Sept, Tabriz University, Tabriz, Iran, pp. 461. (in Farsi)
  7. Isshiki, A., Akimitsu, K., Yamamoto, M. & Yamamoto, H. (2001). Endopolygalacturonase is essential for citrus black rot caused by Alternaria citri but not for brown spot caused by Alternaria alternata. Molecular Plant-Microbe Interactions Journal, 14, 749-757.
  8. Kakvan, N., Zamanizadeh, H., Morid, B., Taheri, H. & Hajmansor, SH. (2012). Study on pathogenic and genetic diversity of Alternaria alternata isolated from citrus hybrids of Iran, based on RAPD-PCR technique. European Journal of Experimental Biology, 2(3), 570-576.
  9. Kang, J., Crous, P., Godwin R., Mchau, A., Serdani, M. & Song, SH. (2002). Phylogenetic analysis of Alternaria spp. associated with apple core rot and citrus black rot in South Africa. Jornal of the British Mycological Society, 106(10), 1151-1162.
  10. Karvalho, D. C. (2008). Conidial production and reaction of Alternaria alternata f.sp. citri to plant extracts. (Annual Report 1940:91). Agricultural Experiment Station Bulletin. 487.
  11. Kohmoto, K., Akimitsu, K. & Otani, H. (1991). Correlation of resistance and susceptibility of citrus to Alternaria alternata with sensitivity to host-specific toxin. Phytopathology, 81, 719-722.
  12. Mahmoudi, E. (2010). Evaluation of citrus cultivars susceptibility to leaf spot disease caused by Alternaria alternata under in vitro conditions. Journal of Research in Agricultural Science, 2, 75- 81.
  13. Peever, T. L., Ibanez, A., Akimitsu, K. & Timmer, L.W. (2002). Worldwide phylogeography of the citrus brown spot pathogen, Alternaria alternata. Phytopathology, 92, 794-802.
  14. Pryor, B. M. & Michailides, T. J. (2002). Morphological, pathogenic, and molecular characterization of Alternaria isolates associated with Alternaria late blight of pistachio. Phytopathology, 92(4), 406-416.
  15. Seif, A. A. & Hillocks, R. J. (1999). Reaction of some citrus cultivars to Phaeoramularia fruit and leaf spot in Kenya. Fruits, 54, 323-329.
  16. Simmons, E. G. (2007). Alternaria An Identification Manual. CBS Biodiversity Series 6. CBS Fungal Biodiversity Centre, Utrecht, The Netherlands.
  17. Tamura, K., Peterson,D. , Peterson, N., Stecher, G. , Nei, M. & Kumar, S. (2011). MEGA5: molecular evolutionary genetics analysis using maximum likelihood, evolutionary distance, and maximum parsimony methods. Molecular Biology and Evolution, 28, 2731-2739.
  18. Timmer, L. W., Roberts, P. D. & Chung, K. R. (2003). Alternaria brown spot (L.W. Timmer). In: Florida Citrus Pest Management Guide, University of Florida, USA, IFAS, 146 pp, Publication No. 43E, 81-83.
  19. Timmer, L. W., Solel, Z., Gottwald, T. R., Ibanez, A. M. & Zitko, S. E. (1998). Environmental factors affecting production, release, and field populations of conidia of Alternaria alternata, the cause of brown spot of citrus. Phytopathology, 88, 1218-1223.
  20. Vicent, A., Badal, J., Asensi, M. J., Sanz, N., Armengol, J. & García-Jiménez, J. (2004). Laboratory evaluation of citrus cultivars susceptibility and influence of fruit size on fortune mandarin to infection by Alternaria alternata pv. Citri. European Journal of Plant Pathology, 110(3), 245-251.
  21. Waller, J. M., Ritchie, B. J. & Holderness, M. (1997). Plant Clinic Handbook. Oxon, New York, pp. 144.
  22. White, T. J., Bruns, T., Lee, S. & Taylor, J. W. (1990). Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: PCR Protocols: A Guide to Methods and Applications. Edited by Innis, M. A., Gelfand, D. H., Sninsky, J. J. & White, T. J. (Academic Press, Inc. New York, N.Y), pp. 315-322.
  23. Woudenberg, J. H. C., Groenewald, J. Z., Binder, M. & Crous, P. W. (2013). Alternaria redefined. Studies in Mycology, 75, 171-212.