辣椒疫霉不同发育阶段对氟吗啉的敏感性研究

Sensitivity of Different Morpha of Phytophthora capsici to Flumorph

从江西省各地采集分离获得108个辣椒疫霉菌株,通过菌丝生长法等测定了辣椒疫霉菌的不同生长阶段对氟吗啉的敏感性。研究结果表明,氟吗啉对辣椒疫霉菌的不同生长发育阶段的抑制作用明显,辣椒疫霉菌丝生长对氟吗啉的敏感性较高,EC50值范围为0.07852～0.38622μg/m L,平均EC50值为0.18159μg/m L;游动孢子囊形成对氟吗啉的敏感性更高,EC50值范围为0.00251～0.03943μg/m L,平均EC50值为0.01588μg/m L;游动孢子萌发对氟吗啉的敏感性最高,EC50值范围为0.00156～0.00965μg/m L,平均EC50值为0.00515μg/m L。正态分析表明,辣椒疫霉菌108个菌株的3个发育阶段对氟吗啉的敏感性符合正态分布,江西省内目前还不存在耐药性的辣椒疫霉群体。

108 single- sporangia isolates of Phytophthora capsici, which can cause capsicum blight, werecollected from several areas in Jiangxi Province and purified, the bioactivity of flumorph against differentstages of Phytophthora capsici was compared in vitro. The results showed that flumorph had significantinhibitory effect on the 3 different growth stages of the strain, mycelial growth of pathogen was affected byflumorph, with a mean EC50 as 0.18159 μg/m L, ranging from 0.07852 μg/m L to 0.38622 μg/m L. The producingof sporangia was more sensitive to flumorph, with a mean EC50 as 0.01588 μg/m L, ranging from 0.00251 μg/m Lto 0.03943 μg/m L. The germination of zoospores of Phytophthora capsici was most sensitive to flumorph, andEC50 distributed from 0.00156 to 0.00965 μg/m L with a mean value of 0.00515 μg/m L. Normal distributionanalysis showed that the sensitivity of these isolates to flumorph was fitted well with a normal distributionfunction, and there was no strain of capsicum blight pathogen that had resistance to the fungicide.