Partridge D E, Sutton T B, Jordan D L
Former Graduate Research Assistant.
Professor, Department of Plant Pathology.
Plant Dis. 2006 Nov;90(11):1407-1412. doi: 10.1094/PD-90-1407.
The effects of soil temperature and moisture, and nine pesticides commonly used in peanut production, on the mycoparasitic activity of Coniothyrium minitans on sclerotia of Sclerotinia minor were evaluated. In vitro mycelial growth and conidia germination of C. minitans were sensitive to azoxystrobin, chlorothalonil, fluazinam, pyraclostrobin, tebuconazole, and diclosulam. C. minitans survived and infected sclerotia of S. minor in the presence of azoxystrobin, chlorothalonil, diclosulam, fluazinam, flumioxazin, S-metolachlor, pendimethalin, pyraclostrobin, and tebuconazole. Mycoparasitic activity was reduced by all pesticides except S-metolachlor compared with the nontreated control. Optimum conditions for infection of sclerotia were temperatures from 14 to 22°C and soil moisture from -0.33 to -1 kPa × 10. Mycoparasitic activity of C. minitans remained high (98% sclerotia infected) at temperatures ranging from 14 to 22°C, but decreased at temperatures above 28°C. Viability of sclerotia was inversely related to the proportion infected by C. minitans (r = -0.9963, P = 0.001). Mycoparasitic activity also declined when soil moisture was greater than -1 kPa × 10 or less than -0.10 kPa × 10. These results indicate that C. minitans should not be applied when temperatures exceed 28°C, during extremes in soil moisture, or when there is a high risk of contact with pesticides before it becomes established in the soil.
评估了土壤温度和湿度以及花生生产中常用的9种农药对小盾壳霉（Coniothyrium minitans）寄生核盘菌（Sclerotinia minor）菌核的菌寄生活性的影响。小盾壳霉的体外菌丝生长和分生孢子萌发对嘧菌酯、百菌清、氟啶胺、吡唑醚菌酯、戊唑醇和双氯磺草胺敏感。在嘧菌酯、百菌清、双氯磺草胺、氟啶胺、乙羧氟草醚、精异丙甲草胺、二甲戊灵、吡唑醚菌酯和戊唑醇存在的情况下，小盾壳霉能够存活并侵染核盘菌的菌核。与未处理的对照相比，除精异丙甲草胺外，所有农药均降低了菌寄生活性。侵染菌核的最佳条件是温度为14至22°C，土壤湿度为-0.33至-1 kPa×10。小盾壳霉的菌寄生活性在14至22°C的温度范围内保持较高水平（98%的菌核被侵染），但在温度高于28°C时下降。菌核的活力与被小盾壳霉侵染的比例呈负相关（r = -0.9963，P = 0.001）。当土壤湿度大于-1 kPa×10或小于-0.10 kPa×10时，菌寄生活性也会下降。这些结果表明，在温度超过28°C、土壤湿度极端或在小盾壳霉在土壤中定殖之前接触农药风险较高时，不应施用小盾壳霉。
