Its blackening is mainly caused by a pathogen, Pseudomonas sp., which is rod-shaped, with one or two flagella growing on one side and can swim in water without capsule. And its metabolic type is respiratory type, and the requirement for nutrition is not very high. As long as there are simple organic compounds and some inorganic salts, it can grow very fast.
Generally, this kind of thing spends winter on the diseased branches and leaves. When the temperature and humidity are suitable for it in the second year, it can carry out schizogenesis. In addition, its spread and invasion are dependent on water, so it can develop very fast in the humid environment.
So in low places or places with more rain, cloves are easy to get sick, and leaves are easy to turn black. But in general, purple is more difficult to get sick than white.
Generally, there are two ways to improve, one is gardening, and the other is to treat with drugs.
1. To solve the problem from the aspect of horticulture is also to solve the problem fundamentally. That is not to plant it in a lower place, so that there will be no water accumulation. In addition, if it rains, we need to drain the rain out in time. When we introduce seedlings, we need to test them well, and can't bring in the plants with diseases.
2. We usually use Bordeaux solution for treatment through drugs. At the beginning, spray 0.1% to 1.0%. Of course, there are some other reagents such as xiaojunling. In addition, we can sprinkle some bleaching powder or sulfur powder under the bush.
