| Abstract: | No registered fungicide controls Mucor piriformis, a cause of severe postharvest storage rot in pears, but the experimental fungicide RH 886 (active ingredients: 77% 5-chloro-2-methylisothiazol-3-(2H)-one and 23% 2-methylisothiazol-3-(2H)-one) has an ED50 of 23.1 μg ml?1 in 5 min exposure for germination of sporangiospores of M. piriformis and an ED50 of 9.9 μg ml?1 for mycelial growth. Mixing RH 886 into infested, amended soil at 8 mg g?1 soil or mixing copper sulfate into soil at 1 mg g?1 soil prevented sporulation of M. piriformis. Application of RH 886 to pear fruits prior to inoculation, or immersion of fruits in solutions of RH 886 containing sporangiospores of M. piriformis significantly reduced fruit infection. |
