This experiment was carried out to find a better cultural technique to avoid or to reduce the severe pepper plant (Capsicum annuum L.) damage caused by Phytophthora capsici which is a prevailing disease in continuous cropping area under plastic film house. Four different transplanting methods were evaluated with 3 cultivars, Garam, Kwari and Chonghong; the crowns of pepper seedlings were planted 1㎝ below soil level (conventional transplanting), crown part leveled with soil surface, crown part raised 4㎝ above soil level, and 15㎝ above soil level with plastic film tube.
First symptom appeared in 10 days after inoculation with zoosporangial suspension of Phytophthora capsici with 1㎝ below planting, 10 to 20 days with the same soil level, 20 days with 4㎝ above soil level and 30 to 40 days with 15㎝ soil level supported with plastic film tube. More than 90% of the infected plants with crown rot symptom were blighted to death within 20 to 40 days. The highest infection rate and degree of disease severity was observed in both conventional transplanting 1㎝ below soil level and the same soil level, followed by 4㎝ above soil level, and 15㎝ above soil level in decreasing order. The lowest percent of plants was infected and even if infected, the disease symptom was the least severe when transplanted 15㎝ above soil level. This suggests that the transplanting method may be one of the most effective ways to prevent pepper plants from being infected by Phytophthora capsici.
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