Lack of an Intron in Cytochrome b and Overexpression of Sterol 14a-Demethylase Indicate a Potential Risk for QoI and DMI Resistance Development in Neophysopella spp. on Grapes.
Lack of an Intron in Cytochrome b and Overexpression of Sterol 14a-Demethylase Indicate a Potential Risk for QoI and DMI Resistance Development in Neophysopella spp. on Grapes.
复制标题
细胞色素 b 中内含子的缺失和甾醇 14a-去甲基酶的过度表达表明 Neophysopella spp. 存在 QoI 和 DMI 抗性发展的潜在风险。
DOI：
10.1094/phyto-11-20-0514-r
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发表时间：
2021
期刊：
影响因子：
3.2
通讯作者：
Santos RF
中科院分区：
文献类型：
--
作者：
Santos RF
亚洲葡萄叶锈病(Neophysopella Meliosmae-myrianthaeand N.)在巴西，热带病通常由苯醌外源抑制物(QOI)和脱甲基化抑制物(DMI)杀菌剂控制。在此，我们评估了55Neophysopellaspp的敏感性。对吡菌酯(QOI)和戊唑醇(DMI)的分离物。为了阐明耐药机制，我们分别分析了QOI和DMI杀菌剂的细胞色素B(Cytb)和细胞色素P450甾醇14α去甲基酶(CyP51)靶蛋白的序列。在一些分离株中也检测了细胞色素P51的表达水平。在叶盘法中，两种菌株对吡虫菊酯的半数有效浓度(EC_(50))平均值约为0.040微克/毫升。所有55个分离物的细胞色素B酶序列完全相同，在第143密码子之后没有内含子。在密码子129、137和143处没有发现氨基酸替代。戊唑醇的EC50值平均值为0.62微克/毫升。托吡卡利和0.46微克/毫升。Meliosmae-myrianthae和noCYP51序列变异在同一种的分离物中被鉴定。然而，五分。在10微克/毫升戊唑醇处理的叶盘上生长的草莓花叶分离物，进一步暴露在戊唑醇选择压力下。戊唑醇适应的实验室分离株。Meliosmae-myrianthei在经过四轮与CYP51靶标改变无关的选择后，抗药性增加了8到25倍。与敏感菌株相比，在测试的四个戊唑醇适应菌株中，有三个菌株在戊唑醇存在下诱导了CYP51的表达。这些结果表明，在新叶蜂中存在QOI和DMI抗性发展的潜在风险。
Asian grapevine leaf rust, caused byNeophysopella meliosmae-myrianthaeandN. tropicalis, is often controlled by quinone outside inhibitor (QoI) and demethylation inhibitor (DMI) fungicides in Brazil. Here, we evaluated the sensitivity of 55Neophysopellaspp. isolates to pyraclostrobin (QoI) and tebuconazole (DMI). To elucidate the resistance mechanisms, we analyzed the sequences of the cytochromeb(CYTB) and cytochrome P450 sterol 14α-demethylase (CYP51) target proteins of QoI and DMI fungicides, respectively. TheCYP51expression levels were also determined in a selection of isolates. In leaf disc assays, the mean 50% effective concentration (EC50) value for pyraclostrobin was about 0.040 µg/ml for both species.CYTBsequences were identical among all 55 isolates, which did not contain an intron immediately after codon 143. No amino acid substitution was identified at codons 129, 137, and 143. The mean EC50value for tebuconazole was 0.62 µg/ml forN. tropicalisand 0.46 µg/ml forN. meliosmae-myrianthae, and noCYP51sequence variation was identified among isolates of the same species. However, fiveN. meliosmae-myrianthaeisolates grew on leaf discs treated at 10 µg/ml tebuconazole, and these were further exposed to tebuconazole selection pressure. Tebuconazole-adapted laboratory isolates ofN. meliosmae-myrianthaeshowed an eight- to 25-fold increase in resistance after four rounds of selection that was not associated with CYP51 target alterations. In comparison with sensitive isolates,CYP51expression was induced in the presence of tebuconazole in three out of four tebuconazole-adapted isolates tested. These results suggest a potential risk for QoI and DMI resistance development inNeophysopellaspp.