1、 Powdery mildew

1. Cause

This disease is caused by powdery mildew. This disease is likely to occur in the open cultivation places in the South and the greenhouse in the north, and the bacteria will spend the winter in the soil, in places with high humidity and weak light, poor ventilation and great temperature difference between day and night. If we water it too much, or plant it too densely, or drought occurs, the disease will be more serious. In the initial stage of this disease, there will be more yellow and white spots on the leaves, which are located on the front of the leaves, while other parts of it are also easy to be infected and may die in severe cases

2. Measures

First of all, we should clean up the weeds that have passed the winter, and then water and fertilize them

Secondly, we should tidy up its branches and remove its leaves, so that all its leaves can receive light and be blown by the wind

Finally, we need to use carbendazim for it. It is also feasible to use lime sulfur mixture of 0.3 and 0.5. Usually once every ten days or three times in a row

2、 White rust

1. Cause

This kind of disease is mainly caused by the bacteria wintering in the soil or on the plant, which will happen in the next season. It can also be spread by artificial field operation. If the flowerpot is too dense, high-pressure water spray will also spread with the water. In the early stage of this disease, small spots will appear on the leaves, which will gradually become larger and then become light yellowish brown. If it is serious, the plant will also die

2. Measures

First of all, fertilizer should be applied. Phosphorus and potassium fertilizer should be increased. This plant will have high resistance to bacteria

Then we should always drain water, and we can't let water accumulate in the basin. We should get rid of weeds and diseased leaves

In the rainy season, 65% of mancozeb or 0.3 to 0.5 stone sulfur mixture should be used at an interval of 10 to 15 days, which can inhibit the spread of the disease. In addition, carbendazim or tobuzin can also be used