对啶酰菌胺敏感性不同的币斑病菌致病性分析

为探究对啶酰菌胺敏感性不同的草坪币斑病菌致病性，本研究根据病原菌对啶酰菌胺的敏感性测定结果，将从天津的高尔夫球场匍匐翦股颖（Agrostis stolonifera）草坪上分离纯化的106株币斑病菌分为高抗（HR）、低抗（LR）、敏感（SS）类型，并在每种类型各挑选2株菌测定菌丝生长速率、生物量、草酸产量，以及接种匍匐翦股颖后的发病率、病情指数，叶片丙二醛（malondialdehyde，MDA）含量。结果表明，对啶酰菌胺敏感性不同的菌株，其致病性存在显著差异。与低抗菌株和敏感菌株相比，高抗菌株生长速率低25.2%左右，生物量少32.4%以上，草酸产量降低27.3%以上，接种匍匐翦股颖后发病率降幅为37.5%以上，病情指数减小49.5%~84.1%，叶片MDA含量降低38.4%以上。总体上看，高抗菌株的致病性最弱，敏感菌株的致病性最强，低抗菌株的致病性介于二者之间。研究结果为草坪币斑病菌对啶酰菌胺的抗性风险评价提供了参考。

Pathogenicity Analysis of Clarireedia spp.with Different Sensitivities to Boscalid

In order to explore the pathogenicity of Clarireedia with different sensitivities to boscalid,the 106 strains of dollar spot pathogens collected from creeping bentgrass(Agrostis stolonifera) in golf courses of Tianjin were classified into three resistance phenotypes:high resistance (HR)，low resistance (LR) and sensitive (SS) strains based on their resistance to boscalid in this study,two strains from each of the above resistance phenotypes,were selected, and the hyphae growth rate,biomass,oxalic acid production of these pathogens were measured;the disease incidence,disease index and malondialdehyde (MDA) content of creeping bentgrass leaves were determined after creeping bentgrass were inoculated by the 6 strains, to evaluate the pathogenicity of pathogens with different sensitivities to boscalid. The results showed that the pathogenicity of dollar spot pathogen strains with different sensitivity to boscalid was significantly different. Compared to the LR and SS strains,the HR strains performed lower hyphae growth rate(decreased by 25.2%),lower biomass(decreased by more than 32.4%) and lower oxalic acid production (decreased by more than 27.3%). Lower diseases incidence(decreased by more than 37.5%), lower diseases index (decreased by 49.5%~84.1%) and lower MDA content in leaves (decreased by more than 38.4%) were found in HR in relative to LR and SS,after inoculating them into creeping bentagrass. In conclusion,the pathogenicity of strains with high resistance to boscalid was the lowest,the pathogenicity of strains that sensitive to boscalid was the highest,and that of LRs was between the two. The results provide useful information for risk assessment of Clarireedia resistance to boscalid.