Frozen Bag Of Mixed Seafood,Frozen Seafood Mix Bag,Mixed Frozen Fish,Bag Of Mixed Seafood Zhejiang Zhoufu Food Co., Ltd. , https://www.zhoufu-food.com
Fusarium oxysporum f. sp. chrysanthemum is the pathogen responsible for this disease, which belongs to the genus Fusarium. This fungus primarily survives in the soil as chlamydospores or through a long saprophytic life cycle. The optimal temperature range for its growth is between 24–28°C, with a maximum of 37°C and a minimum of 17°C. The disease specifically affects chrysanthemums, and under favorable conditions, infected plants can die within just two weeks. Fields that are wet or waterlogged are particularly vulnerable, especially after heavy rains, during periods of high temperatures, excessive nitrogen fertilizer use, soil acidification, or poor drainage. In the field, the pathogen spreads mainly through irrigation water, and it can also be carried by wind, making it highly contagious.
The initial symptoms include yellowing of the leaves, wilting, and a light brown discoloration at the base of the stem. The vascular bundles at the base of the stem turn brown, and as the infection progresses upward, the vascular tissue becomes pale brown. As the disease spreads downward, the roots may become necrotic, black, or rot. Some stems may develop cracks. Under high humidity, a white mold appears on the surface, which consists of the fungal mycelium and conidia. The disease tends to spread slowly, but some plants may show signs of yellowing, wilting, or rot.
To manage the disease, several control methods can be employed. First, selecting disease-resistant local varieties and planting in well-drained sandy soils is essential. Second, proper field management is crucial—using compost or well-fermented organic fertilizers, managing irrigation carefully, and ensuring good drainage to avoid waterlogging after rain. Crop rotation with non-host plants is also recommended. Third, chemical control measures include applying a 50% carbendazim wettable powder solution diluted 500 times, or a 50% copper hydroxide wettable powder solution diluted 400 times. Alternatively, a 30% basic copper sulfate suspension can be applied at a 400-fold dilution, using 0.4–0.5 liters per plant, and repeating the treatment 2–3 times depending on the severity of the infection. These strategies help reduce the impact of the disease and protect chrysanthemum crops effectively.