Department of Entomology, Phytopathology and Molecular Diagnostics, Faculty of Environmental Management and Agriculture, University of Warmia and Mazury in Olsztyn, Olsztyn, Poland.
Department of Food Plant Chemistry and Processing, Faculty of Food Sciences, University of Warmia and Mazury in Olsztyn, pl. Cieszyński 1, 10-726, Olsztyn, Poland.
BMC Microbiol. 2020 Aug 5;20(1):242. doi: 10.1186/s12866-020-01885-6.
Yeasts, which are ubiquitous in agroecosystems, are known to degrade various xenobiotics. The aim of this study was to analyze the effect of fungicides on the abundance of natural yeast communities colonizing winter wheat leaves, to evaluate the sensitivity of yeast isolates to fungicides in vivo, and to select yeasts that degrade propiconazole.
Fungicides applied during the growing season generally did not affect the counts of endophytic yeasts colonizing wheat leaves. Propiconazole and a commercial mixture of flusilazole and carbendazim decreased the counts of epiphytic yeasts, but the size of the yeast community was restored after 10 days. Epoxiconazole and a commercial mixture of fluoxastrobin and prothioconazole clearly stimulated epiphyte growth. The predominant species isolated from leaves were Aureobasidium pullulans and Rhodotorula glutinis. In the disk diffusion test, 14 out of 75 yeast isolates were not sensitive to any of the tested fungicides. After 48 h of incubation in an aqueous solution of propiconazole, the Rhodotorula glutinis Rg 55 isolate degraded the fungicide in 75%. Isolates Rh. glutinis Rg 92 and Rg 55 minimized the phytotoxic effects of propiconazole under greenhouse conditions. The first isolate contributed to an increase in the dry matter content of wheat seedlings, whereas the other reduced the severity of chlorosis.
Not sensitivity of many yeast colonizing wheat leaves on the fungicides and the potential of isolate Rhodotorula glutinis Rg 55 to degrade of propiconazole was established. Yeast may partially eliminate the ecologically negative effect of fungicides.
真菌广泛存在于农业生态系统中，已知其能够降解各种外来化合物。本研究旨在分析杀菌剂对冬季小麦叶片定殖的天然酵母群落丰度的影响，评估酵母分离物对体内杀菌剂的敏感性，并筛选出能够降解丙环唑的酵母。
生长季节使用的杀菌剂通常不会影响定殖在小麦叶片上的内生酵母的数量。丙环唑和氟硅唑与苯醚甲环唑的商业混合物以及多菌灵降低了附生酵母的数量，但在 10 天后酵母群落的大小得到了恢复。环丙唑醇和氟嘧菌酯与丙硫菌唑的商业混合物明显刺激了附生菌的生长。从叶片中分离出的主要物种为出芽短梗霉和粘红酵母。在圆盘扩散试验中，75 株酵母分离物中有 14 株对测试的杀菌剂均不敏感。在丙环唑水溶液中孵育 48 小时后，粘红酵母 Rg55 分离株可降解 75%的杀菌剂。在温室条件下，分离株 Rh. glutinis Rg92 和 Rg55 最小化了丙环唑的植物毒性效应。第一个分离株有助于增加小麦幼苗的干物质含量，而另一个分离株则降低了黄化的严重程度。
许多定殖在小麦叶片上的真菌对杀菌剂不敏感，并且分离出的 Rhodotorula glutinis Rg55 具有降解丙环唑的潜力。酵母可能部分消除了杀菌剂的生态负效应。
