Early Tea Tea Plant Diseases and Pest Control Ideas
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I. Occurrence characteristics of major pests and diseases
1, tea caterpillars, also known as poison caterpillars. The larvae colonize before the third instar and adult phototaxis. Young larvae mostly inhabit the back of the lower part of the tea tree and take the lower epidermis and leaves. After the 2nd instar, they can eat holes or nicks, and after 4 years of age, they enter the gluttony period. In severe cases, they can also cause baldness in tea gardens.
2, tea feet è – also known as arch worms. It takes larvae to eat tea leaves, young larvae damage after the formation of spots or nicks, after 3rd indwelling residual whole leaves, when large can make a piece of tea garden bald.
3, false eye small green leafhopper, also known as leafhoppers. It pierces the shoots and veins of the tea tree with a needle-like mouthpiece and sucks sap, resulting in dehydration and atrophy of the bud, which seriously affects the yield and quality of the tea. The worm is the main pest of our city in recent years.
4. Tea pods are also known as tea leaf locusts. The worms are mixed and overlapping in generations and can occur in more than 10 generations a year. Each of the worms can be overwintering in the old and old leaves, and its eggs are spawned on the back of the young leaves, especially in the sideways depressions. It absorbs the juice from the tea tree and makes the damaged sprouts lose luster. The veins turn red and the leaves roll up and shrink. When they are serious, they cause the leaves to dry, and the leaves have brown rust spots on their backs, affecting the yield and quality of the tea. From mid-May to late June, mid-July to late August, the damage is heavier.
5. Tea anthracnose mainly damages leaves and old leaves. The lesions are often from the leaf margins or tip, becoming water-stained dark green, round, and then gradually expanding, becoming irregular, gradually turning reddish-brown, becoming greyish white at the later stage, with distinct disease and health boundaries. There are many small, black bumps on the lesions, without ridges. The incidence is usually in rainy years, and at the same time, the partial application of nitrogen fertilizer is also easy to occur in tea gardens.
Second, prevention and control measures (1) increase organic fertilizer: Tea garden organic fertilizer can reduce the damage of acarids, but also reduce the root-knot nematode tea and some leaf diseases.
(2) Shallow ploughing and weed control: After weeding (10 cm or so) of weeds after the spring tea in the tea gardens is harvested, the insects inhabiting the soil such as the tea worm can be eliminated.
(3) Pay attention to drainage: During the rainy season, it is particularly important for the tea gardens with high groundwater levels to drain the ditch, which can reduce the damage caused by the hypnozoites (such as tea grower, tea leaf spot, etc.).
(4) Control of chemicals: Insect pests such as small green leafhopper, tea leafhopper and tea leaf roller from late May to June can be used with 2.5% rotenone emulsion or Bt at the peak of egg hatching or when young larvae occur. Preparation 300 - 500 times liquid control, safety interval of 3-5 days; can also choose to use 10% bifenthrin or 5% AVS 1500 times control, safety interval of 7-10 days. The amount of avermectin 1.8% was used to control tea aphids.