Studies On The Anastomosis Group Of Rhizoctonia Solani Isolated From Leguminaceous Crops And Their Redifferentiation In Xinjiang

250 idolated of Rhizoctonia solaniwere collected and identified from diseased tissuse of stem,root and soil samples from Leguminaceous crops in xinjiang.Through Safranin O-KOH method staining,all strains belonged to multinucleate Rhizoctonia solani ,nuclear numbers were 3-16,average nuclear numbles was 5.975.According to the test of anastomosis groups method, 250ofisolatesof R.solani werecategorizedasfollows:AG-1,AG-2,AG-3,AG-4andAG-5,Their frequency were 16.4%,33.2%,0.4%32.4% and 17.6%.The result indicated that main AG was AG2andAG4.Through classifyingbyvegetativecompatibilitygroupsmethod,AG1,AG2,AG4 and AG5 were further divided into 2 vegetative compatibility groups respectively.The results fully showed that the anaostomosis group of Rhizoctonia solani isolated from Leguminaceous crops in xinjiang exist some extent intraspecies differentiation.The comparisons of cultural characteristics of each of AG and VCG showed that there were significant differences in the colorandtheshapeofthecolony,stucture,size,thenumberofarialhyphae,quantity,color,dist-ributionofsclerotia,orcolorof culturemedia.MeanwhiletheVCGofthesameAGweresignficantdifferentinculturalproperties.Throughtemperteuregradienttest,theresultindicatedthatdifferentrepresentive strains the minimum growth temperteure was 5-10℃, the preference growthtemperteure was 25-30℃,the maximum of most of them was 40℃.The results of pathogenicitytest indicated :AG-2 had the strongest pathogenicity in Vicia faba.L.,Vigna sinensis (L.),Dolichos lablab.L.,Phaseolus coccineus,and its disease index was 62.38%7,6.2%,75.67%,91.6% respectively；AG-1had the strongestpathogenicityin ArachishypogaeaL.,and itsdiseaseindex was 80.1%；AG-4 had the strongest pathogenicity in Pisum sativum L.,Phaseolusvulgaris L.,and its disease index was 88.57% and 71.7%.By using PCR-RFLP analysis in AGandVCG,Hint?candifferentiatebetween R.SandR.spp.ThroughHaeШenzymedigested,AG2andAG5hadsamebandsrespectively,AG3had evident differencewithotherAGs.eachofVCGinthesame AG had little difference in location ofbands.EveryVCG in the same AG had difference andexistedindegreeredifferentiation.