عنوان مقاله [English]
نویسندگان [English]چکیده [English]
The effects of gamma irradiation doses on spore germination of Trichoderma harzianum and its effects on morphological variation and antagonistic capability of the mutants to control Rhizoctonia solani were evaluated. Spore suspension of Trichoderma has been gamma irradiated with 0, 50, 100, 150, 200, 250, 300, 350, 400 and 450 Gry in Nuclear Agricultural Research School (Nuclear Science and Technology Research Institute, Karaj). Gamma ray effects on mycelial growth were evaluated by irradiation with 0, 400, 800, 1200, 2000 and 2500 Gry. The results showed that the 450 Gry gamma radiations completely blocked the spore germination and 250 Gry was the optimum dose to induce mutation in Trichoderma. Furthermore, gamma irradiation could change the morphological characteristics such as colony shape and color, sporulation and mycelia growth rate. The dual culture test showed that the mutated isolates have statistically higher antagonistic capability against R.solani than their parent strain. According to these results, the bio-control capability of Trichoderma could be improved through the gamma radiation.
 R. Moradi, S. Shahbazi, H. Ahari Mostafavi, M. Mirmajlesi, M. Ebrahimi Determine the appropriate dose of radiation to induce mutations and study on morphological effects in Trichoderma fungi, First Congress of science and new technologies in agriculture, Zanjan University, 29 (2011) 10-12.
 R. Vilgalis, M.A. Cubeta, Molecular systematics and population biology of Rhizoctonia Annual Review of Phytopathology, 32 (1994) 135-155.
 D.E. Carling, S. Kuninaga, K.A. Brainard, Hyphal anastomosis reaction, DNA- internal transcribed spacer sequences, and virulence levels among subsets of Rhizoctonia solani anastamosis group- 2 (AG2) and AG-BI, 92 (1996) 43-50.
 W.M. Haggag, H. Abdel-Latif, A. Mohamed, Biotechnological aspects of microorganisms used in plant biological control, American-Eurasian Journal of Sustainable Agriculture, 1 (2007) 7-12.
 C.R. Howell, Mechanisms employed by Trichoderma species in the biological control of plant diseases: the history and evolution of current concepts, USD/ARS southern plains Agricultural Research center (2009).
 I. Chet, G. E. Harman, R. Baker, Trichoderma hamatum: Its hyphal interactions with Rhizoctonia solani and Pythium spp, Microbial Echology, 7 (1) (2005) 29-38.
 H.R. Etebarian, Evaluation of Trichoderma isolates for biological control of charcoal stem rot in melon caused by Macrophomina phaseolina, Journal of Agriculture Science Technology, 8 (2006) 243-250.
 S. Shahbazi, R. Moradi, N. Safaei, H. Ahari Mostafavi, M. Mirmajlesi, Detoxification of fusarium Doxynivalenon using Glucosyl-transferase, The First National Conference on Sustainable Agriculture, Azad University, 1 (2011) 1-4.
 H. Ahari Mostafavi, The application of nuclear technology in the management of weeds and plant diseases, Second National Conference on the application of nuclear technology in agricultural sciences and natural resources, Nuclear Science and Technology Research Institute, (2008) 331-335.
 C.R. Howell, The role of antibiosis in bicontrol. In Harman, G. E. and Kubicek, C.P. (eds.). Trichoderma and Gliocladium, Taylor and Francis, Londan (1998) 173-184.
 M. Baek, C.R. Howell, C.M. Kenerley, The role of an extracellular chitinase from Trichoderma virens (Gv29-8) in the biocontrol of Rhizoctonia solani, Curr. Genet. 35 (1999) 41-50.
 M. Mukherjee, R. Hadar, P.K. Mulherjee, B.A. Horwitz, Homologus expression of a mutated beta-tubulin gene dose not conferes benomyl resistance on Trichoderma harzianum, J. Applied Microbiol, 95 (2003) 861-867.
 T.A. Muusa, M.A. Rizk, Impact of gamma radiation stresses on control of sugarbeet pathogens R. solani and S. rolfsii, Pakistan J. of Plant Pathology, 2(1) (2003) 10-20.
 W.M. Haggag, Induction of hyperproducing chitinase Trichoderma mutants for efficient biocontrol of Botrytis cinerea on tomato and cucumber plants growing in plastic houses, Arab J. Biotech, 5(2) (2002) 151-164.
 H. Abdel-Latif, A. Mohamed, W.M. Haggag, Biocontrol potential of salinity tolerant mutants of Trichoderma harzianum against Fusarium oxysporum causing tomato wilt disease, Arab J. Biotech, 8 (1) (2005) 35-48.
 H. Ahari Mostafavi, M. Mirjalili, M. Mirmajlesi, H. Fathollahi, M. Mansouri Pour, The effect of gamma rays on the spore germination and hypha growth of Penicillium expansum, Third National Conference on the application of nuclear technology in agricultural sciences and natural resources, Nuclear Science and Technology Research Institute, (2010) 485-479.
 H. Ahari Mostafavi, N. Safaei, B. Naserian, H. Fathollahi, H. Dorri, Evaluation of biological control of bean root rot disease using non-pathogenic mutants of Fusarium solani f.sp. phaseoli, J. of Research in plant production (Agricultural Sciences and Natural Resources), 16 (3) (2007) 33-42.
 B. Sneh, M. Zeidan, M. Ichielevich-Austet, I. Barash, Y. Koltin, Increased growth responses induced by a non pathogenetic isolate of Rhizoctonia solani, Can. J. Bot. 64 (1989) 2372-2378.
 C.E. Windels, D.J. Nabben, Characterization and pathogenicity of anastamosis group of Rhizoctonia solani, isolated from Beta vulgaris Phytophatology, 79 (1989) 83-88.