The Damage Caused by the Infection of Water Melon with CGMMV-W at Several Stage of Plant Growth

Abstract

1. Survey was done to know about disease severity of water melon inoculated with CGMMV-W at different growing stage of plant in field.
2. The latent period of this virus in the plant seemed to be about 15 days regardless. with growing stage.
3. The symptom on the leaves was mosaic with green mottle and it varried in severity as the plant grew.
4. The plant growth was poor with virus infection at any stage and damage was more. severe at the earlier infection.
5. The fruit was also affected when the plant was infected. The number of fruit decreased with earlier infection, and in case of the later infection many small fruit were set on the plants without any symptom.
6. If the plants were infected at the young fruiting stage, the fruit flesh became soften. However, the fruit of the plant infected at the other stages was fiberous. Even at the. later infection, the healthy marketable fruits were no more than 30% of the total yield of normal plants.
7. With these facts, it was indicated that the metabolism was disturbed in the diseased plant just after the infection, subsequently the fruits flesh became soft.