What are the control methods for anthracnose in gardenia?
[Symptoms] The disease mainly affects the leaves of gardenia. It starts from the leaf tip and leaf margin, forming irregular or nearly circular brown spots. Sometimes the entire leaf turns brown, and in severe cases it causes branch dieback or the death of the whole plant. The disease mostly starts on the lower leaves of the plant. Under humid conditions, small black dots are produced on the spots on both sides of the leaves, with more small black dots on the underside of the leaf (the upper side bears acervuli, the underside bears perithecia).
[Pathogen] The pathogen is Colletotrichum gloeosporioides, belonging to the Deuteromycotina. The conidia are cylindrical, colorless, unicellular. The acervuli are initially embedded beneath the host epidermis, later breaking through the epidermis and becoming exposed. The setae are dark brown, straight or slightly curved, with 1 to 2 septa. The conidiophores are cylindrical, colorless, measuring 10-20 um x 1.5-2.5 um. The conidia are cylindrical, slightly curved, colorless, unicellular, measuring 12-20 um x 4-7 um, often containing 1 to 2 oil droplets.
[Occurrence pattern] The fungus overwinters as mycelium latent on diseased leaves. In the following spring, when temperature and humidity are suitable, conidia are produced for infection. A characteristic of this pathogen is that it can also form a large amount of the sexual state, namely perithecia, during the growing season. High temperature and high humidity conditions favor the disease. During transport of gardenia seedlings, in poorly ventilated, hot and humid environments, the incidence of the disease is relatively high.
[Control methods] 1. Agricultural control. Promptly remove diseased fallen leaves and destroy them in a centralized manner to reduce sources of infection. Manage water and fertilizer scientifically, appropriately increase the application of organic fertilizer and phosphorus-potassium fertilizer, and avoid excessive nitrogen fertilizer. When watering, do so as much as possible in the morning and water thoroughly each time. 2. Chemical control. Before the disease occurs, spray 1% Bordeaux mixture for prevention to protect the plants. During the disease period, spray 50% Shibaogong 1000x solution or 10% Shigao 1000x solution, 430 g/L Haolike 2500x solution, 75% chlorothalonil wettable powder 500-800x solution, etc.
Control methods for anthracnose in gardenia
Symptoms
The disease mainly harms the leaves of gardenia. The disease mostly starts on the lower leaves of the plant; on infected leaves, small brown round spots form, and the entire leaf gradually turns yellow and falls off. The disease can also occur from the leaf tip and leaf margin, forming irregular brown spots, and the entire leaf gradually turns brown, becomes hard in texture and falls off. Severely affected plants can drop a large number of leaves and cause branches or even the whole plant to die. Under humid conditions, small black dots are produced on the spots on both sides of the leaves, with more small black dots on the underside of the leaf (the upper side bears acervuli, the underside bears perithecia).
Pathogen and current disease situation
This disease is a fungal disease caused by infection with Glomerella cingulata. The pathogen mainly overwinters as mycelium latent in the soil, and in the following spring when temperature and humidity are suitable, it forms conidia for infection. A characteristic of this fungus is that it can also form a large amount of the sexual state, namely perithecia, during the growing season. High temperature and high humidity conditions favor the disease. In the Beijing area, it occurs from April to October. During transport of gardenia seedlings, in poorly ventilated, hot and humid environments, the incidence of the disease is relatively high.
Control methods
1. Promptly remove diseased fallen leaves and destroy them in a centralized manner to reduce sources of infection.
2. Chemical control. Before the disease occurs, spray 1% Bordeaux mixture to protect the plants from infection; during the disease period, spray 75% chlorothalonil wettable powder 500-800x solution.
3. In the early stage of the disease, irrigate the rhizosphere soil with ferrous sulfate (black alum) 30-50x solution, or alternately irrigate with "alum fertilizer water" (made by mixing and composting 2.5 kg ferrous sulfate, 5 kg soybean cake, and 15 kg pig manure, then applying after 10-15 days of fermentation and decomposition) and clear water. A 0.1%-0.2% ferrous sulfate aqueous solution can also be sprayed on the leaves.
Gardenia anthracnose
1. Symptoms:
The disease mainly harms the leaves of gardenia. The disease mostly starts on the lower leaves of the plant; on infected leaves, small brown round spots form, and the entire leaf gradually turns yellow and falls off. The disease can also occur from the leaf tip and leaf margin, forming irregular brown spots, and the entire leaf gradually turns brown, becomes hard in texture and falls off. Severely affected plants can drop a large number of leaves and cause branches or even the whole plant to die. Under humid conditions, small black dots are produced on the spots on both sides of the leaves, with more small black dots on the underside of the leaf (the upper side bears acervuli, the underside bears perithecia).
2. Pathogen and current disease situation:
This disease is a fungal disease caused by infection with Glomerella cingulata. The pathogen mainly overwinters as mycelium latent in the soil, and in the following spring when temperature and humidity are suitable, it forms conidia for infection. A characteristic of this fungus is that it can also form a large amount of the sexual state, namely perithecia, during the growing season. High temperature and high humidity conditions favor the disease. In the Beijing area, it occurs from April to October. During transport of gardenia seedlings, in poorly ventilated, hot and humid environments, the incidence of the disease is relatively high.
Control methods:
1. Promptly remove diseased fallen leaves and destroy them in a centralized manner to reduce sources of infection.
2. Chemical control. Before the disease occurs, spray 1% Bordeaux mixture to protect the plants from infection; during the disease period, spray 75% chlorothalonil wettable powder 500-800x solution.
3. In the early stage of the disease, irrigate the rhizosphere soil with ferrous sulfate (black alum) 30-50x solution, or alternately irrigate with "alum fertilizer water" (made by mixing and composting 2.5 kg ferrous sulfate, 5 kg soybean cake, and 15 kg pig manure, then applying after 10-15 days of fermentation and decomposition?? - experience of flower growers in Yanling, Henan) and clear water. A 0.1%-0.2% ferrous sulfate aqueous solution can also be sprayed on the leaves.