The Occurrence of Black Spot of Cauliflower and Ways to control

1. symptoms
The disease is a fungal type, which primarily affects the leaves and petioles. Disease spot starts from the outer leaves or the bottom leaves. The grey circular spot will expand and grow black filar mold. When plant is affected by the mold, its growth can be greatly affected. The germinating rate is very low and the seedlings are thin and small.
2. The rule of occurrence of disease. The bacteria live across the winter mycelia or conidiophore with invalidity plants in the soil. In appropriate conditions, infection can occur and proper temperature （17-25 ℃) with high humidity will make it easy to occur.
3. prevention measures
1, strengthen management of cultivating
① apply full maturing organic fertilizer, conform to NPK formulation to avoid deficiency to enhance the disease resistance of plants; ② use disease resistance varieties or four percent of tobacco farmers-120-200 melons to soak the seeds to effectively prevent the occurrence of seedling diseases;
③ rotation with other vegetables;
④ Rationally close planting;
⑤ reasonable watering, reduce humidity, promptly drainage to prevent accumulation of stagnant water after the rain;
⑥ attention to health of the field, promptly removed diseased leaves, uprooting the diseased plants, and concentrate them to bury or burn to avoid cross-infection.
2, Chemical control. In the early seedling stage, spray chemical solution once every 10-15days. Spray 2-3times in a row. (Reproduced)