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What are the diseases and insect pests of primrose and the control methods of diseases and insect pests of primrose

Prevention and control of diseases and insect pests of primrose: leaf spot and withered branch disease often occur in spring, which can be sprayed with 1500 times solution of 50% bacillus special wettable powder. Spring pests often include aphids and coir moths, which can be sprayed with 1000 times of phoxim EC. Pruning and shaping: pruning and pruning as appropriate after falling leaves in winter, cut off dense branches and withered branches, and truncate long branches to keep the tree beautiful and constantly updated, and can promote more flowering in the following year.

The main diseases of primrose are leaf spot and branch blight. Symptoms of leaf spot disease: infected with leaf spot disease of primrose, there will be small brown spots on the leaves, then yellow on the edges of the leaves, followed by withered leaves, and even lead to the death of primroses.

Leaf spot disease, symptoms, early leaves have many brown spots, gradually enlarged, leaf margin dry, leaves yellowing. The methods of prevention and treatment were sprayed with copper succinate wettable powder or 4000 times streptomycin wettable powder after the attack. Spot disease, brown spots on the leaves, 3-4 mm in diameter. In severe cases, the leaves of the plant withered and even fell.

[prevention and treatment] at the initial stage of the disease, 70% chlorothalonil wettable powder 1000 times liquid and other fungicides were sprayed. Botrytis cinerea is one of the common diseases of primrose, which occurs all over the country. After the plant was infected, the whole plant yellowed and withered. The disease mainly infects leaves, tender stems, floral organs and other parts, and mostly occurs at leaf tip and leaf edge. At the beginning of the disease, the leaves appeared water-immersed spots, and then gradually expanded, turned brown and rotted.

The natural enemies of aphids are ladybugs, aphid flies, parasitoids, aphid-eating gall mosquitoes, crab spiders and lacewings, which can artificially capture pests to treat aphids. Most families use potted primroses, which are mostly used for large-scale planting in gardens. however, when pot cultivation is maintained outside, the natural contact of aphids will reduce the occurrence of aphids.

Main diseases and insect pests of primrose and their control methods

1. Prevention and control of diseases and insect pests of primrose: leaf spot and withered branch disease often occur in spring, which can be sprayed with 1500 times solution of 50% bacillus special wettable powder. Spring pests often include aphids and coir moths, which can be sprayed with 1000 times of phoxim EC. Pruning and shaping: pruning and pruning as appropriate after falling leaves in winter, cut off dense branches and withered branches, and truncate long branches to keep the tree beautiful and constantly updated, and can promote more flowering in the following year.

2. As soon as the prevention and control method is found, immediately spray chlorothalonil wettable powder to sterilize. The symptoms of Botrytis cinerea were similar to those of mosaic disease. after the plant was infected, the whole plant yellowed and died. The method of prevention and control can remove the diseased leaves and plants in time so as to reduce the source of infection. When you get sick, you can spray Sukeling or Prohydantoin wettable powder solution for 2 or 3 times.

3. Secondly, control aphids and reduce transmission media. Symptom prevention and treatment methods Brown spots appear on the leaves of plants. Once the brown spot is found, immediately spray chlorothalonil wettable powder to sterilize. The prevention and treatment of symptoms is similar to that of mosaic disease. After the plant infection, the whole plant turned yellow and died. Botrytis cinerea timely removal of diseased leaf disease plants, reduce the source of infection. When you get sick, spray milk or propylene wettable powder for 2-3 times.

What is the reason why the branches and leaves of primrose turn yellow?

The leaves of primrose turn yellow, which may be caused by lack of light, so it is necessary to replenish the light at this time. It is a kind of plant that is not resistant to waterlogging, and its leaves are easy to turn yellow if it is not watered properly. It may also be a normal phenomenon, because it is a deciduous shrub plant, and its leaves will turn yellow and fall off at the end of autumn.

The reason for the yellowing of primrose leaves is that the soil permeability is poor: primroses are usually planted in the open field or potted outdoor maintenance, wind and rain can also grow normally. Especially in the rainy season, the drainage of the soil is poor, the stagnant water in the basin is not removed in time, and the root respiration is blocked, thus affecting the growth of the plant.

Soil discomfort: primrose may be planted to provide it with the soil is not suitable for growth, the soil permeability is very poor, but also easy to plate, will cause the leaves to yellowing. Lack of moisture: when raising primrose, it is watered too little or not watered, so that it can not absorb enough water, which has an adverse effect on its growth, so that the leaves gradually turn yellow.

Reasons for reducing watering: primrose is more afraid of waterlogging, especially in the rainy season or too much water, there is no way to discharge it in time, its roots can not breathe normally, and the leaves will turn yellow. Solution: the right amount of watering, must not be based on feeling, if too much water can bask in the sun after watering, it is best to check the soil before watering, if it is moist, you do not need watering.

Primrose leaves yellowing and wilting how to do environmental mutation: if the conservation environment is suddenly changed during maintenance, it is difficult to adapt, there will be leaf yellowing or dry phenomenon. Pay attention to the maintenance period do not casually change the growth environment, want to change the environment should be carried out step by step.

The reason for the yellowing of primrose leaves is that the soil permeability is poor. Primroses are generally planted in outdoor open fields or pots for maintenance and can grow normally in wind and rain. Especially in the rainy season, the soil drainage is not smooth after the rain, the water in the basin is not removed in time, and the root respiration is blocked, which affects the plant growth. In fact, there is no fixed time for each kind of flower to be watered too often. Flower lovers have too much water, dry air and high temperature because of their feelings. This is not right.