Prevention and control of tea coal disease

Tea coal disease, also known as black oil, soot disease, etc., is distributed in various tea areas across the country, mainly harmful leaves, branches and leaves surface of the primary black, nearly round to irregular spots, and then extended to the whole leaf, so that the leaf surface is covered with a layer of soot-like black mold, there are nearly ten kinds, its color, thickness, density are slightly different, let's take a look at the prevention and control methods of tea coal disease!

Harmful symptoms of tea coal disease

Tea coal disease is mainly harmful to leaves, the branches and leaves are initially black, nearly round to irregular spots, and then spread to the whole leaf, so that the leaves are covered with a layer of soot-like black mold. There are nearly ten kinds of tea coal smoke disease, which are slightly different in color, thickness and compactness. among them, the mildew layer of thick-colored tea coal disease is thick, loose, and black short thorn hairs grow in the later stage, and sometimes black whitefly, scale, aphids and so on can be seen on the back of diseased leaves. Serious occurrence occurred in the first tea stage and the fourth tea stage, when the tea garden was black, only the top tea buds remained green, the growth of bud leaves was inhibited, photosynthesis was blocked, and the yield and quality of tea were affected.

Conditions for the occurrence of tea coal disease

Most of the pathogens of tea coal disease overwintered in the diseased part with mycelium and conidia or ascomycetes. In the next spring, spores are produced on the mildew layer and spread by wind and rain. After spores fall on the secretions of whiteflies, scales or aphids, they absorb nutrients for growth and reproduction, and can be transmitted through the activities of these pests. The above pests are often an important prerequisite for the occurrence of the disease. Tea gardens with extensive management or shade and dampness, moisture retention after rain and serious pests are prone to disease.

Prevention and control of tea coal disease

1. Starting with strengthening the management of the tea garden, timely and appropriate pruning, creating good ventilation and light transmission conditions, timely drainage after rain, strictly preventing moisture retention, and doing everything possible to strengthen the tree potential to prevent the occurrence of the disease.

2. Timely control of tea garden pests and pay attention to the control of whitefly, scale insects, aphids and other pests is one of the positive and effective measures to control the disease. For specific methods, see this book on tea pests.

3. In early spring and late autumn, 0.5% stone sulfur mixture or 0.7% lime half-dose Bordeaux solution, 30% Ludebao suspension 500 times, 47% Garinon wettable powder 700 times, 12% green copper EC 600 times were sprayed in early spring and late autumn.