Baseline Sensitivity of Natural Population and Resistance of Mutants in Phytophthora capsici to Zoxamide
Baseline Sensitivity of Natural Population and Resistance of Mutants in Phytophthora capsici to Zoxamide
复制标题
自然群体对苯草酰胺的基线敏感性和辣椒疫霉突变体的抗性
DOI：
10.1094/phyto-01-11-0010
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发表时间：
2011-09-01
期刊：
影响因子：
3.2
通讯作者：
Hao, Jianjun J.
中科院分区：
文献类型：
--
作者：
Bi, Yang;Cui, Xiaolan;Hao, Jianjun J.
通过室内试验确定了辣椒疫霉菌对苯酰菌胺的敏感性基线和产生抗性的风险。在中国共收集到158个辣椒疫霉分离物。所有158个菌株均对苯酰菌胺敏感，其50%抑制菌丝生长的有效浓度为0.023~0.383 μ g/ml，平均浓度为0.114 μ g/ml，呈偏单峰分布。用紫外线照射辣椒疫霉菌丝培养物和游动孢子，或在唑菌胺修饰的平板上适应培养物，获得抗唑菌胺的辣椒疫霉突变体。抗性选择频率平均为1.8 × 10~（-7）。抗性菌株也来自自交或杂交两个性相容的菌株，导致平均选择频率为0.47。辣椒疫霉突变体对苯酰菌胺的抗性因子为25~100。通过10次培养转移，突变体保持高水平的RF（14和134之间），并有几乎相同的健身作为他们的野生型亲本在菌丝生长，孢子形成，和毒力。苯酰菌胺与氟吗啉、甲霜灵、嘧菌酯、烯菌唑均无交互抗性。根据以上结果，辣椒疫霉可对苯酰菌胺产生抗性，并且预测其自然风险为中等。
Laboratory experiments were conducted to determine the baseline sensitivity of Phytophthora capsici and its risk for developing resistance to zoxamide. In total, 158 P. capsici isolates were collected from China. All 158 isolates were sensitive to zoxamide, with effective concentrations for 50% inhibition of mycelial growth of 0.023 to 0.383 mu g/ml and a mean of 0.114 mu g/ml, which showed a skewed unimodal distribution. Zoxamide-resistant mutants of P. capsici were obtained by either treating mycelial culture and zoospores with ultraviolet irradiation or adapting a culture on zoxamide-amended plates. The frequency of resistance selection averaged 1.8 x 10(-7). Resistant isolates were also derived by selfing or crossing two sexually compatible isolates, resulting in a mean selection frequency of 0.47. The resistance factor (RF) for zoxamide was 25 to 100 in P. capsici mutants. Through 10 culture transfers, the mutants maintained high levels of RF (between 14 and 134) and had almost equal fitness as their wild-type parents in mycelial growth, sporulation, and virulence. There was no cross resistance between zoxamide and either flumorph, metalaxyl, azoxystrobin, or etridiazole. Based on the results above, P. capsici can develop resistance to zoxamide, and the risk is predicted to be moderate in nature.