2849

2782

كارشناسي ارشد

بيماري شناسي گياهي

اصفهان: دانشگاه صنعتي اصفهان، دانشكده كشاورزي

1383

يازده، 99، [II]ص.: مصور، جدول، شكل، نمودار

مسعود بهار، بهرام شريف نبي

احمد مرتضوي

1384/4/27

رحيم عبادي، حسين سماواتيان

1396/10/26

كتابنامه

كشاورزي

مهندسي كشاورزي

ID2782

به فارسي و انگليسي: قابل رويت درنسخه ديجيتالي

Abstract Certain species and subspecies of Pectobacterium sp cause blackleg and soft rotdiseases in potato Due to their differences in adaptation to diverse climates overwintering and survival in soil or seed tuber it is important to identify the causalagent of potato blackleg in each region precisely For detection and identification ofcausal agent of potato blackleg in Isfahan and some other potato growing areas thepotato fields were surveyed during 2003 2004 Of the diseased plants sampled 54bacterial strains were isolated which on the basis 0 f morphological and biochemicalcharacteristics and also pectolytic activities they were recognized as pecobacterium sp According on their biochemical and physiological test results the isolates werecategorized in two different groups The first group including 43 isolates were knownas P chrysanthemi due to positive reaction for phosphatase and non reducing substancesfrom sucrose ability of growth at 37 C production of indole and acid from arabinose melibiose lactose and maltose The remained 11 isolates were placed in the second group which were absoloutly similar to P carotovorum subsp carotovorum insome biochemical characteristics sush as production of acid from trehalose maltose andlactose producing acid from palatinose and I methyl D glucoside ability of growth at37 C and failure to produce of phosphataseand reducing substance from sucrose Noneof the isolates could have been recognized as P atrosepticum To confirm the results ofbiochemical tests polymerase chain reaction employed and a 434 bp fragment obtainedin isolates which had been recognized as Pcc in biochemical testes by applying primerpair Y IN 2 RFLP analyzing of this fragment showed that mentioned isolates belong togroups 1 6 9 14 defined as Pcc Also using primer set ExpccF ExpccR lead toamplification 0 fa 550 bp fragment in DNA extracts of those isolates although thisfragment was not obtained from isolates belonging to Pa and Pch Primer pairADEtl ADE2 was able to distinguish strains identified as Pch in this study from theothers by producing a 420 bp fragment Using Ecalf Eca2r and Y 4sN 46primer pairs 690 and 434 bp fragments were amplified in standard isolate Eca SCRII043respectively but failed to produce the same fragment from the other isolates Thisfinding proved the non existence of Pa in potato samples collected from Isfahan which showed blackleg symptoms These primers could also detect at least 102 cfu ml of the Eca SCRII043 grown in pure culture Using GtILI primers made it possible to detect Pa Pcc and Pch in one PCR reaction By utilizing this primer set ITS region of the bacteria were amplified On the basis of band patterns obtained from GtILt the isolates placed in three groups The first group of ITS PCR comprised only the standard isolate Eca SCRII043 and such a pattern could have been observed in none of collected isolates Isolates which were identified as Pcc by biochemical tests placed into the second group and finally the third group was including isolates that known as Pch regarding to biochemical and physiological tests By using ITS RFLP analyses the results obtained from ITS PCR method were confirmed Therefore in this research Ecalf Eca2r ExpccF ExpccR and ADEt ADE2 were recognized as valuble primer pairs for detection of Pcc Pa and Pch respectively d I J A I u iI l V J II

مسعود بهار، بهرام شريف نبي

احمد مرتضوي

رحيم عبادي، حسين سماواتيان