©1994-2010ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.http://www.cnki.net西瓜专化型尖孢镰刀菌的分离鉴定及水稻根系分泌物对其生长的影响苏世鸣,任丽轩,杨兴明,徐阳春,周俊,沈其荣3(南京农业大学资源与环境科学学院,江苏南京210095)摘要:利用尖孢镰刀菌选择性培养基从西瓜枯萎病发病部位分离出病原菌,通过Booth′s镰刀菌分类鉴定标准和专化型试验,确定该菌株为西瓜专化型尖孢镰刀菌(Fusariumoxysporumf1sp.niveum)。以该菌株为材料,研究水稻根系分泌物对其生长的影响。结果表明,2个水稻品种ELIO和4007的根系分泌物均能显著抑制其孢子萌发和孢子产生。当根系分泌物的加入量为115mL时,ELIO和4007对孢子萌发的抑制率分别为3718%和4110%;当加入20mL水稻根系分泌物时,ELIO和4007对孢子产生的抑制率达到9613%和7614%。水稻根系分泌物对西瓜尖孢镰刀菌孢子产生过程的抑制作用主要发生在孢子萌发阶段和孢子在尖孢镰刀菌瓶状小梗上的生成阶段,而对菌丝营养生长没有影响。西瓜与旱作水稻间作的盆栽试验表明,间作系统中西瓜苗的鲜重和株高分别提高了18610%和8015%。单作西瓜枯萎病发病率为6617%,死亡率为4414%,而间作处理中西瓜均生长正常。间作条件下,西瓜根际土壤中的尖孢镰刀菌数量显著降低,与单作根际土壤相比减少了91%。表明:水稻根系分泌物能显著抑制西瓜专化型尖孢镰刀菌生长,采用旱作水稻与西瓜间作能有效缓解西瓜枯萎病的发生。关键词:西瓜;水稻;尖孢镰刀菌;根系分泌物中图分类号:Q945112;S43214+4文献标识码:A文章编号:1000-2030(2008)01-0057-06IdentificationoftheFusariumoxysporumf1sp.niveumandtheeffectsofricerootexudatesonitsgrowthSUShi2ming,RENLi2xuan,YANGXing2ming,XUYang2chun,ZHOUJun,SHENQi2rong3(CollegeofResourcesandEnvironmentalSciences,NanjingAgriculturalUniversity,Nanjing210095,China)Abstract:Thepathogenofwiltdiseasewasisolatedfromtheinfectedwatermelonplantsusingselectivemedium.Accordingtothesymptoms,morphologyandpathogenicity,thepathogenwasidentifiedasFusariumoxysporumf1sp.niveum.RicerootexudatesofbothELIOand4007werecollectedtoinvestigatetheeffectsofthemonthesporedevelopmentofF1oxysporumf1sp.niveum.TheabsolutevalueofinfluenceratiotosporegerminationofF1oxysporumf1sp.niveumwas3718%and4110%,withadding115mLrootexudatesofELIOand4007,respectively.TheabsolutevalueofinfluenceratiotoF1oxysporumf1sp.niveumreproductionreached9613%and7614%,withadding20mLrootexudatesofELIOand4007,respectively.PotexperimentswerecarriedouttoinvestigatetheeffectofintercroppingwithaerobicriceonFusariumwiltinwatermelon.Theresultsshowedthatfreshweightandplantheightofwatermelonseedlingsincreasedby18610%and8015%inintercroppingsystem,respectively,comparedwiththoseinmono2croppingsystem.6617%ofwatermelonwereinfectedwithwiltdiseaseand4414%diedafter40daysoftransplantinginmono2croppedsoil,butthosewerenormallygrowninintercroppingsystem.ThedensityofF1oxysporumdecreased91%ininter2croppedrhizospheresoilcomparedwithmono2croppedsoilafter40daysoftransplanting.Itissuggestedthatintercroppingwithaero2bicricealleviatedFusariumwiltinwatermelon,byrestrainingthesporereproductionandsporegerminationofF1oxysporumf1sp.niveumthroughtheproductionofricerootexudates.Keywords:watermelon(Citrulluslanatus);rice;Fusariumoxysporum;rootexudates随着我国农业产业结构的调整,西瓜栽培面积不断扩大,连作障碍已成为制约西瓜生产的重要因素[1]。枯萎病是西瓜连作障碍的主要病害之一,其病原菌为西瓜专化型尖孢镰刀菌(Fusariumoxyspo2rumf1sp.niveum)[2]。在研究克服连作障碍方面已经做了大量的工作,如选育抗病品种[3],嫁接[4],药收稿日期:2006-11-17基金项目:科技部973项目(2007CB109304);农业部948项目(2006-G62);南京农业大学青年科技创新基金项目(KJ04006)作者...
