ABSTRACT

These studies were carried out to investigate the reason for leaf-wilt of melon in protected cultivation at local farm lands in Naju, Chunnam province. Nine farm fields with severe leaf-wilt symptoms and six farm fields with light leaf-wilt symptoms were surveyed to compare the soil physiochemical properties and inorganic nutrient contents in plant. Also, growth characteristics and root distribution in soil were compared for melon plants with severe and light leaf-wilt symptoms.

The farms with severe symptoms of leaf-wilt phenomena were applied heavy organic matter 4,867 kg/10a(cow manure ), but the farms with light symptom were applied 2,492 kg/10a. Melon production was 2,771 kg/10a for severe farmer fields and 3,207 kg/10a for light farmer fields. Leaf-wilt phenomena of melon was caused by high moisture content in the soil and high hardness of soil which induced bad penetration of water.  In the soil where severe symptoms occurred, EC and cation contents, such as K. Ca, Mg, Na, were very high.  This indicated that many kinds of salts were accumulated in the soil, and chemical properties in the soil were unbalanced. Therefore, root growth was poor, and water absorption rate by roots was lower than transpiration rate in leaves.

RESULTS

Table 1. Correlation coefficient between leaf-wilt symptom degree and soil chemical properties and inorganic nutrient contents in the leaves of melon