5293

4963

كارشناسي ارشد

بيماري شناسي گياهي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1388

سيزده،88ص.:مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

بهرام شريف نبي

مسعود بهار

29/3/89

امير مساح، مجيد طالبي

1395/08/23

مهندسي كشاورزي

ID4963

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Rapid and Sensitive Detection of Rosellinia necatrix Causal Agent of White Root Rot Disease Using Conventional and Specific Primers Methods Seyd Morteza Mohammadi Meymand meymandnab@yahoo com Date of Submission 2010 3 9 Department of Plant Protection Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiB Sharifnabi Assoc Professor Supervisor sharifna@cc iut ac irAbstractWhite root rot caused by Rosellinia necatrix Prill is one of the most important disease on fruit treesin Iran and world wide Although the range of host comprises is more than 170 plant species damagesresulted from this disease is important in regards of wilting and death of the fruit trees Control of thewhite root rot is complicated by its ubiquitarian presence in the soil and by a number of specificcharacteristics including resistance to drought tolerance to a wide range of soil pH high number ofhosts and penetration deep into the soil and resistance to various common fungicides Therefore control of white root rot should be mainly based on the avoidance of the pathogen through the use ofcertified healthy propagative materials and new plantings in non infested soils To achieve a simpleand sensitive pathogen detection method in soil and root this investigation was conducted Eighteenisolates of R necatrix were obtained from root of cherry and apple and confirmed using speciesspecific primer R2 and R8 To study genetic diversity PCR RFLP of ITS region using MboI MspIand HinfI restriction enzymes was applied The result revealed that there was no genetic diversityamong isolats using PCR RFLP Soil direct culture method root infected in culture medium NestedPCR method and pathogen trapping using twig Bait were used to determine the best method ofpathogen detection Among used methods the direct culture method from soil was not suitable andwasn t sensitive for detection However other methods were capable to detect which the Nested PCRwas better than other Relation ship among primary inoculum time needed for detection andsymptoms occurrence showed that by increasing in primary inoculum more time is needed fordetection and disease symptoms To verify the accuracy of the used detection method ITS resion wascoloned in pTZ57R T vector and sequenced Comparison of the sequenced showed 98 99 similarityto recognized isolate of R necatrix In conventional PCR using primer pairs R2 R8 10 pg l 1 wasamplified however in Nested PCR by R7 R10 primer pairs 1 fg l 1 was amplified enable thedetection of R necatrix gave a detectable amplification product of template DNA in direct PCR andin artificially inoculated soils The results revealed that NestedPCR method of detection in soils androot is more sensitive and reliable Key words Detection White Root Rot Rosellinia necatrix Nested PCR pathogen

بهرام شريف نبي

مسعود بهار

امير مساح، مجيد طالبي