2011). Integrated control of cucumber black root rot using chloropicrin fumigation in polyethylene-mulched beds of resistant rootstock of Cucurbita ficifolia. Jpn. J. Phytopathol. 77: 278-286. Black root rot of cucumber (Cucumis sativus) caused by Phomopsis sclerotioides is a serious greenhouse disease in many countries. Since 2001, the disease has been observed on outdoor-cultivated cucumber grafted on pumpkin rootstock in the Tohoku region of Japan, causing severe economic losses. We sought

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... establish control measures against black root rot of cucumber grafted on pumpkin rootstock caused by P. sclerotioides in outdoor culture in the Tohoku region of Japan. Soil fumigants chloropicrin (298.5 L a.i./ ha), dazomet (294 kg a.i./ha), metham sodium (180 L a.i./ha), and fluazinam (15 kg a.i./ha) were evaluated for efficacy in naturally infested fields. Because it reduced sudden wilting, chloropicrin was selected for subsequent experiments to develop effective control. Partial fumigation (injection into polyethylene-mulched beds) gave adequate control, better than overall fumigation in fields. Partial fumigation significantly reduced sudden wilt incidence by 77% and 100% compared to untreated plots, and overall fumigation yielded 54% and 100% reduction in two experiments. For chloropicrin injection into polyethylene-mulched beds, a 90-cm width of the beds was better than the common practice of 60-cm width. Since the 90-cm width disinfested a wide area, we concluded that control was high (90-cm width significantly reduced sudden wilt incidence by 95% and 100% compared to untreated plots, and 60-cm width yielded 70% and 82% reduction in two experiments). However, these treatments did not completely control sudden wilt. Combining these treatments with the use of resistant rootstock C. ficifolia, which by itself suppressed disease from 56% to 100% in three experiments, reliably decreased the incidence of sudden wilt by 100% reduction in three experiments compared to the untreated plots. The efficacy of each control measure alone varied, so integrated methods are preferable.