Gardenia Anthracnose: Control Methods and Detailed Introduction to Treatment Fungicides

[Symptoms] This disease mainly affects the leaves of gardenia. It starts at the leaf tips and leaf margins, forming irregular or nearly circular brown lesions. Sometimes the entire leaf turns brown, and in severe cases it causes branch dieback or 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 lesions 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, single-celled. 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 1-2 septa. The conidiophores are cylindrical, colorless, measuring 10-20 um x 1.5-2.5 um. The conidia are cylindrical, slightly curved, colorless, single-celled, measuring 12-20 um x 4-7 um, often containing 1-2 oil droplets.

[Occurrence pattern] The fungus overwinters as mycelium latent in diseased leaves. In the following spring, when temperature and humidity are suitable, it produces conidia for infection. A characteristic of this pathogen is that it can also form large amounts of the sexual state, namely perithecia, during the growing season. High temperature and high humidity favor disease development. During the transport of gardenia seedlings, poorly ventilated, hot and humid environments result in a higher disease incidence.

[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; apply appropriate amounts of organic fertilizer and phosphorus-potassium fertilizer, and avoid excessive nitrogen fertilizer. When watering, do so in the morning as much as possible, and water thoroughly at one time. 2. Chemical control. Before disease onset, spray 1% Bordeaux mixture for prevention to protect the plants. During disease onset, 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 Gardenia Anthracnose

Symptoms

This 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 drops off. The disease can also occur from the leaf tips and leaf margins, forming irregular brown lesions, and the entire leaf gradually turns brown, becomes hard in texture and drops off. Severely affected plants may drop a large number of leaves and even cause branches or the whole plant to die. Under humid conditions, small black dots are produced on the lesions 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 Status

This disease is a fungal disease caused by infection with Glomerella cingulata. The pathogen mainly overwinters as mycelium latent in the ground, 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 large amounts of the sexual state, namely perithecia, during the growing season. High temperature and high humidity conditions favor disease development. In the Beijing area, it occurs from April to October. During the transport of gardenia seedlings, poorly ventilated, hot and humid environments result in a higher disease incidence.

Control Methods

1. Promptly remove diseased fallen leaves and destroy them in a centralized manner to reduce sources of infection.

2. Chemical control. Before disease onset, spray 1% Bordeaux mixture to protect plants from infection; during disease onset, spray 75% chlorothalonil wettable powder 500-800x solution.

3. In the early stage of disease, ferrous sulfate (black vitriol) 30-50x solution can be used to irrigate the rhizosphere soil, or "alum fertilizer water" (ferrous sulfate 2.5 kg, soybean cake 5 kg, pig manure 15 kg mixed and composted, applied after 10-15 days of fermentation and decomposition) can be used alternately with clear water for irrigation. A 0.1%-0.2% ferrous sulfate aqueous solution can also be sprayed on the leaves.

Gardenia Anthracnose

1. Symptoms:

This 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 drops off. The disease can also occur from the leaf tips and leaf margins, forming irregular brown lesions, and the entire leaf gradually turns brown, becomes hard in texture and drops off. Severely affected plants may drop a large number of leaves and even cause branches or the whole plant to die. Under humid conditions, small black dots are produced on the lesions 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 status:

This disease is a fungal disease caused by infection with Glomerella cingulata. The pathogen mainly overwinters as mycelium latent in the ground, 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 large amounts of the sexual state, namely perithecia, during the growing season. High temperature and high humidity conditions favor disease development. In the Beijing area, it occurs from April to October. During the transport of gardenia seedlings, poorly ventilated, hot and humid environments result in a higher disease incidence.

Control methods:

1. Promptly remove diseased fallen leaves and destroy them in a centralized manner to reduce sources of infection.

2. Chemical control. Before disease onset, spray 1% Bordeaux mixture to protect plants from infection; during disease onset, spray 75% chlorothalonil wettable powder 500-800x solution.

3. In the early stage of disease, ferrous sulfate (black vitriol) 30-50x solution can be used to irrigate the rhizosphere soil, or "alum fertilizer water" (ferrous sulfate 2.5 kg, soybean cake 5 kg, pig manure 15 kg mixed and composted, applied after 10-15 days of fermentation and decomposition?? - experience of flower growers in Yanling, Henan) can be used alternately with clear water for irrigation. A 0.1%-0.2% ferrous sulfate aqueous solution can also be sprayed on the leaves.