菊花菌核病病原菌鉴定、抗性筛选与防治

菌核病是菊花生产中的一种重要病害。为明确菊花菌核病病原菌的种类、品种抗性差异和有效的防治药剂,本研究采用组织分离法对病原菌进行分离培养,结合形态学特征、生物学特征和分子生物学研究进行鉴定,并筛选了33个切花菊品种以及7种杀菌剂。结果表明,从感病植株上分离得到的病原菌能够重新感染菊花,并且再次分离得到的菌株与原菌株相同。通过病原菌的形态、感染特征和分子序列分析,确定了该病原菌为核盘菌(Sclerotinia sclerotiorum)。病原菌在酵母浸出粉胨葡萄糖培养基(YEPD)上的生长速度最快,在20~30℃时生长最好,在pH值5~7时生长较快,对碳源的种类要求不严格,以蛋白胨为氮源时生长较好。共筛选了33份菊花材料,未发现免疫及抗病品种,有6份中抗品种,13份中感品种,14份感病品种,且离体与活体接种差异性不大。氟酰胺和肟菌酯对核盘菌具有显著抑制效果,半数效应浓度(EC;)分别为0.09 mg·L^-1和0.65 mg·L^-1;此外,通过接种后喷施杀菌剂发现,氟酰胺和肟菌酯的防治效果分别达到了98.26%和90.93%,显著优于其他杀菌剂。本研究建立了菊花菌核病的鉴定、筛选与防治的基本方法,为后续菊花抗性育种与品种改良奠定了基础。

Pathogen Identification,Resistance Screening and Control of Chrysanthemum Sclerotinia sclerotiorum

Sclerotinia sclerotiorum is an important disease in chrysanthemum production.In order to clarify the pathogen species,varietal resistance differences and effective fungicides of chrysanthemum S.sclerotinia,the pathogen was isolated and cultured by tissue isolation method,and identified by morphological,biological and molecular studies,then 33 cultivars of cut chrysanthemum and 7 fungicides were screened.The results showed that the pathogen isolated from the infected plants could infect chrysanthemum again,and the strain isolated again was the same as the original strain.The pathogen was identified as S.sclerotiorum by morphological analysis,infection characteristics and sequence analysis.The results showed that the growth of pathogen on YEPD medium was the fastest;the growth was the best at 20~30℃;the pathogen could grow faster at pH 5~7;there was no strict requirement for the type of carbon source;and the growth was better when peptone was used as nitrogen source.A total of 33 chrysanthemum materials were screened,and no immune and disease resistant varieties were found,including 6 moderately resistant varieties,13 moderately susceptible varieties and 14 susceptible varieties.In addition,the difference between in vitro and in vivo inoculation was not significant.Flutolanil and trifloxystrobin had very good inhibitory effect on S.sclerotiorum,with EC;of 0.09 mg·L^-1and 0.65 mg·L^-1,respectively.In addition,spraying fungicides after inoculation showed that the control effect of flutolanil and trifloxystrobin reached 98.26%and 90.93%respectively,which was significantly better than other fungicides.In this study,the basic methods of identification,screening and control of chrysanthemum S.sclerotiorum were established,which laid a foundation for the subsequent resistance breeding and variety improvement of chrysanthemum.