The Complete Guide to Iron Diseases and Their Prevention in the Netherlands

Dutch iron disease 1: leaf spot

Disease pattern

The pathogens of leaf spot disease usually spend the winter living on diseased plant remains. They may spread and infect plants in greenhouses, fields, and home potted plants during rainy weather and water splashing. Their tiny size allows them to invade plants through wounds or stomata. In a high temperature and high humidity environment, the stomata of plants are enlarged, making them more susceptible to disease.

symptom

In the early stage of the disease, the pathogen mostly invades from the leaf edges and tips. At first, it appears as small faded green spots that look like water stains. If the weather is dry, the disease will be more obvious at the junction of the diseased and healthy parts, appearing as concave dark-brown semicircular spots. It is more dangerous in a high temperature and high humidity environment, with obvious water stains and irregular leaf spots. As the number of lesions increases, the leaf tips will dry up, the entire leaf will become necrotic, and even bacterial pus may be seen.

Prevention and treatment methods

1. Eliminate diseased and damaged parts promptly and burn them in batches.

2. Enhance light and air permeability. The humidity in the greenhouse should not be too high. Avoid splashing when watering. It is best to water along the edge of the pot to reduce the chance of spreading infection.

3. After the disease is discovered, you should pay attention to spraying pesticides in the early stage. You can use 77% of the wettable powder of Copper Chloride and 1:500 solution of water, 800 times solution of 30% copper oxychloride suspension, 800 times solution of 47% of Carranon wettable powder, 4000 times solution of 72% agricultural streptomycin or mycobacterium sulfate soluble powder, etc.

Dutch iron disease 2: Anthracnose

Disease pattern

symptom

The disease mainly infects the tips and edges of leaves, and the symptoms are roughly the same as leaf spot. In the early stages of the disease, the disease appears as moist brown spots, sometimes with pink mucus. After spreading, the spots appear as semicircular or oval, reddish purple or dark brown spots with light brown or gray in the center. After the onset of the disease, they will gradually expand, and brown ring-shaped spots will appear around them. The spots will gradually shrink and dry up. There are black particles on the spots. When the disease is severe, the entire leaf will turn yellow and wither.

Prevention and treatment methods

① Drain water in time to prevent moisture retention, apply organic fertilizer, and increase the amount of phosphorus and potassium fertilizers.

② Prune and remove diseased and damaged parts in time, and bury or burn them uniformly.

③When the bacteria infect the Dutch iron plant in large areas and cause it to become ill, it is necessary to spray pesticides. Spray with lime sulfur solution or suspension, 100% solution of basic copper sulfate (apply before the disease occurs), 100% solution of copper sulphate, 100% solution of agricultural water-resistant agent, or 100% solution of Amisida suspension, 100% solution of thiophanate-copper.