5292

4962

كارشناسي ارشد

بيماري شناسي گياهي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1388

سيزده،94ص.:مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

مسعود بهار

علي آهون منش

29/3/89

امير مساح، مجيد طالبي

مهندسي كشاورزي

ID4962

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Molecular Characterization of Aster Yellows group Phytoplasmas Group 16S rRNAI in Central Part of Iran Fereshteh Vaali Fereshtehv 62@gmail com Date of submission 02 03 2010 Department of plant pathology Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi M Bahar Ph D Assistant Professor Supervisor Mbahar@cc iut ac ir A Ahoonmanesh Ph D Professor Supervisor Aliahoon@cc iut ac ir Abstract Candidatus phytoplasma asteris belongs to 16SrI Aster yellows group causes yellowing whitches broom leaf stunting and phyllody symptoms in different plant hosts such as vegetable field crops fruit trees and ornamentals Losses induced by C Phytoplasma asteries are mainly economic and lead to significant reduction in crop yield and quality Aster yellows group phytoplasmas are now considered to divide in several subgroups on the basis of the nucleotide sequence of conserved genes In recent years Ca Phytoplasma asteris has been reported as the causal agent of phytoplasma diseases of several plants in Iran Although the phytoplasma has been detected from different locations in central part of Iran the prevalence of subgroups related to aster yellows in the region phytoplasmas is unknown The purpose of this study reported here was to analysis the genetic differences of Candidatus Phytoplasma asteris strains detected in central part of Iran to determine their relevant subgroups During 2008 2009 various vegetables field crops ornamentals and weeds showing phytoplasma symptoms including yellowing and hyacinth leaves phyllody witches broom excessive branching of axillary shoots and general stunting were collected from Esfahan Chaharmahal va Bakhtiari Yazd and Markazi provinces of Iran DNA was extracted from the midribs and petiols of the samples through Muray and Thompson method Direct PCR method using P1 P7 primer pairs was employed to detect phytoplasma 16 S rRNA sequences as the amplification target region The PCR amplification with purified DNA as template yielded the expected 1800bp product from some of the samples but not from all the samples tested Use of nested PCR increased the sensitivity of detection over single round PCR Using primer pairs R16F2n R16R2 in nested PCR after the first round PCR with primer pairs P1 P7 directed to detect a 1240 bp fragment in the majority of the samples showing phytoplasma associated symptoms Specificity of the test was validated as no amplification was found in case of negative control plants Nested PCR successfully identified 67 phytoplasma associated diseases among 120 samples In order to distinguish Ca Phytoplasma asteris based on amplified fragment from 16S 23S intergenic spacer region using primer pairs R16F2n R16R2 HhaI CfoI restriction endonuclease analysis was performed The results on the basis of the pattern of restriction fragments suggest that there is a sufficient

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علي آهون منش

امير مساح، مجيد طالبي