Longan Disease: Leaf Spot Disease, Flower Rot Disease
Entomopathogenic Fungi: Colletotrichum sp.
It generally spreads, particularly in the humid climate. In case of severe epiphytotic, the leaf loses the photosynthesis area and will fall eventually. If it happens to the flower, it will rot and fall during blooming period. Fungus living on the leaf blows with the wind or contaminates with steam to ruin the fruit. Consequently, there is no pollination and the flowers become rotten and give low fruits.
Prevention and Elimination
1. Use Geraj 200 cc. to drain water from the flower to prevent rotten flower, or Radacim 300-400 cc. (usage rate is per 200 ltr. of water).