Survey of some of ascospore characteristics of rapeseed blackleg disease for differentiating Leptosphaeria maculans and L. biglobosa in some areas of Mazandaran and Golestan provinces
Subject Areas : دو فصلنامه تحقیقات بیماریهای گیاهی
A. Zaman Mirabadi
1
,
K. Rahnema
2
,
M. Sadravi
3
,
M. Salati
4
1 - مربی پژوهش، مرکز تحقیقات کاربردی و تولید بذر شرکت توسعه کشت دانه های روغنی، ساری، ایران.
2 - دانشیار، گروه گیاه پزشکی، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان، ایران
3 - دانشیار، گروه گیاه پزشکی، دانشگاه یاسوج، یاسوج، ایران
4 - استادیار پژوهش، مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی، مشهد، ایران.
Keywords: Rapeseed, Leptosphaeria maculans, Leptosphaeria biglobosa, blackleg, Ascospore,
Abstract :
Ascospore dimensions of eight populations of Leptosphaeria maculans and L. biglobosa, causal agents of rapeseed blackleg disease, isolated from debris of rapeseed (Brassica napus) and wild mustard (Sinapis arvensis) were evaluated in Mazandaran and Golestan provinces. Results of ANOVA indicated significant differences in the dimensions of ascospores of the different populations. The greatest length and width of sexual spores were 87.5 and 12.5 micrometer, respectively. Variations in the range of Length and width of ascospores in the studied populations was measured, 46.25 and 7.5 micrometer, respectively also these variations were 6.25 and 2.5 micrometers greater than the dimensions of ascospores reported by other studies in the world. The length of sexual spores isolated from stem debris of mustard was much bigger than those of canola. Germination percentage of most studied populations was more than reported in other studies, so likely the most of studied populations of different regions belong to non aggressive group. Sexual spores of aggressive types have greater number of germ tubes, shorter in length, twisted and originate from the middle cells. While in the nonaggressive type the germ tubes grow out of end cells and are not twisted. With regard to morphological characteristics of sexual spore germ tube and also cotyledon test characteristics, field symptoms, pigment production and colony growth rate it was determined that ascospores of the studied populations from Dasht-e-Naz of Sari, Kohikheil and Fazel Abad were of the aggressive type (L. maculans) and most of population in Lala, Mazarustaq and Talookola areas belonged to nonaggressive type (L. biglobosa). There was no correlation between germ tube characteristics of fungus populations on mustard and their pathogenicity.
Brun H, Levivier S, Eber F, Renard M and Chevre AM. 1997. Electrophoretic analysis of natural populations of Leptosphaeria maculans directly from leaf lesions. Plant Pathology 46: 147–154.
Fitt BDL, Hu BC, Barbetti MJ and Rimmer SR. 2006. World-breadth importance of phoma stem canker (Leptosphaeria maculans and L.biglobosa) on oilseed rape (Brassica napus). European journal plant pathology 114: 3–15.
Huang YJ, Toscano-Underwood C, Fitt BDL, Todd AD, West JS, Koopmann B and Balesdent MH. 2001. Effects of temperature on germination and hyphal growth from ascospores of A-group and B-group Leptosphaeria maculans (phoma stem canker of oilseed rape). Annals of Applied Biology 139: 193–207.
Jensen LB.1994. First record of ascomata of Leptosphaeria maculans on winter-grown oilseed rape in Denmark. Plant Pathology 43 (4): 759–761.
Johnson RD and Lewis BG. 1994. Variation in host range, systemic infection and epidemiology of Leptosphaeria maculans. Plant Pathology 43(2): 269–277.
Koch E, Badawy HMA and Hoppe HH. 1989. Differences between aggressive and non-aggressive single spore lines of Leptosphaeria maculans in cultural characteristics and phytotoxin production. Journal of phytopathology 124: 52–62.
McGee DC and Petrie GA. 1978.Variability of Leptosphaeria maculans in relation to blackleg of oilseed rape. Phytopathology 68: 625–630.
Mengistu A, Rimmer SR, Koch E and Williams PH. 1991. Pathogenicity grouping of isolates of Leptosphaeria maculans on brassica napus cultivars and their disease reaction profiles on rapid-cycling brassicas. Plant disease 75: 1279–1282.
Mengistu A, Rimmer RS and Williams PH. 1993. Protocols for in vitro sporulation, ascospore release, sexual mating, and fertility in crosses of Leptosphaeria maculans. Plant Disease 77: 538–540.
Ndimande B. 1976. Studies on Phoma lingam (Tode ex. Fr.j Desm. and the Dry Rot on Oilseed Rape. Brassica napus (L.) var. oleifera Metzger [PhD]. [Uppsala]: Agricultural College of Sweden.
Petrie GA. 1988. The rapid differentiation of virulent and weakly virulent strains of Leptosphaeria maculans (blackleg or stem canker) and related pycnidial fungi Brassica seeds and stems. Canadian Journal of Plant Pathology 10: 188–190.
Punithalingam E and Holliday P. 1972. Leptosphaeria maculans. CMI descriptions of pathogenic Fungi and Bacteria. No. 331.
Salisbury PA, Ballinger DJ, Wratten N, Plummer KM and Howlett BJ. 1995. Blackleg disease on oilseed Brassica species in Australia: A review. Australian Journal of Experimental Agriculture 35: 665–672.
Smith HC and Sutton BC. 1964.Leptosphaeria maculans the ascogenous state of Phoma lingam. Transactions of the British Mycological Society 47: 159–165.
Toscano-Underwood, Westa, CJS, Fitta BDL, Todda AD and edryczka, MJ. 2001. Development of phoma lesions on oilseed rape leaves inoculated with ascospores of A-group or B-group Leptosphaeria maculans (stem canker) at different temperatures and wetness durations. Plant Pathology 50: 28–41.
West JS, Kharbanda PD, Barbetti MJ and Fitt BDL. 2001. Epidemiology and management of Leptosphaeria maculans (phoma stem canker) on oilseed rape in Australia, Canada and Europe. Plant Pathology 50: 10–27.
Zaman Mirabadi A, Mehdi Alamdarlou R, Esmailifar A and Fathi H. 2010a. Distribution of Leptosphaeria maculans in Iran. Paper presented at: 19th Iranian Plant Protection Congress; 31 July – 3 August; Tehran, Iran.
Zaman Mirabadi A, Rahnama Kand Esmaailifar A. 2009a. First report of pathogenicity group 2 of Leptosphaeria maculans causing blackleg of oilseed rape in Iran. Plant Pathology 58: 1175.
Zaman Mirabadi A, Rahnama K, Sadravi M and Mehdi Alamdarlou R. 2009b. First report of Leptosphaeria maculans teleomorph on canola stem in the north of Iran. Rostaniha 9(1): 128–130.
Zaman Mirabadi A, Rahnama K, Sadravi M and Salati M. 2010b. Identification, distribution, symptomology and population structure of the causal agents of rapeseed blackleg (Leptosphaeria maculans and Leptosphaeria biglobosa) in Mazandaran and Golestan provinces and determination of three common cultivars susceptibility reaction of rapeseed. Iranian Plant Disease 45(4): 285–267.
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