Effect of slaked lime on controlling clubroot of broccoli and its influence on the plant growth

Abstract

The application of slaked lime is expected to increase soil pH. In this study, we examined the effect of slaked lime on clubroot of broccoli and its influence on the plant growth. We also investigated the chemical properties of the soil and micronutrient contents in the plant. Application of 400–500 kg/10 a to gray lowland soil, which is the major soil type in the Kagawa Prefecture, resulted in maintaining a stable yield of broccoli, and in suppressing clubroot development without showing micronutrient deficiencies. We found that the slaked lime application by combining Amisulbrom wettable powder treatment in nursery boxes was practically effective on controlling the disease in the severely infested field. However, micronutrient contents in broccoli tended to decrease due to the increase of insoluble forms of micronutrients, suggesting that micronutrient deficiencies may occur after applying slaked lime in fields.