Common diseases and insect pests and control methods of yellowing leaves of rich trees

1. Leaf spot:

Leaf spot disease is a fungal disease, in the initial stage of the disease, there will be some small brown spots on the leaf edge or leaf tip, the disease spot will turn gray or grayish brown in the later stage of the disease, and some small black spots will grow in the wet condition.

Prevention and control methods:

1. If the branches and leaves of the rich tree are too dense, it will lead to poor ventilation, and poor ventilation will easily lead to the occurrence of diseases and insect pests.

2. Once leaf spot disease is found, spray 65% Actinomyces wettable powder or 50% thiophanate methyl at the initial stage of the disease. Sulfur suspension 800 times solution, 30% basic copper sulfate suspension 400 times solution, 75% Dakonine wettable powder 700 times solution, etc. Once every 10 days.

Pest control knowledge of rich trees: common diseases and insect pests and control methods

Disease and pest control knowledge of rich trees

Yellow leaf

First, water yellow: caused by excessive watering, which is characterized by no obvious change in old leaves and yellowing of young leaves, which should be controlled immediately.

Second, dry yellow: caused by lack of water, drought, its characteristic is from bottom to top old leaves first yellow, if the lack of water for a little longer, it will be the whole plant yellow leaves, or even death, should be timely watering.

Third, fat yellow: caused by excessive fertilization or high concentration; characterized by thick, shiny and uneven young leaves; fertilizer, ploughing and watering should be controlled.

Fourth, hungry yellow: caused by insufficient fertilizer, low fertilization concentration, and long interval of fertilization; it is characterized by yellow young leaves and tender stems, and if it is not fertilized in time after seeing this phenomenon, it will also cause yellow leaves and even death of the whole plant; for flowers that lack fertilizer, do not apply a large amount of thick fertilizer at one time, so as not to cause root burning.

Fifth, iron deficiency yellow leaves: woody flowers in greenhouse, etc., due to great changes in soil fertility conditions, yellow leaves often appear, characterized by obvious young leaves, light old leaves, yellow mesophyll, green veins, and forming a typical network; ferrous sulfate solution can be used to solve the problem, the method is as follows: 7 parts of cake fertilizer, 5 parts of ferrous sulfate and 200 parts of water.

Root rot disease

Root rot is a common disease that seriously harms rich trees, also known as rot.

Prevention and cure method

(1) keep the cultivation environment dry and attach importance to the disinfection of cultivation media and sites.

(2) after the semi-finished products are unloaded into the operation shed, the head of the wealth tree is sprayed with Sukeling to prevent the harm of Botrytis cinerea.

(3) cut off the sprained and rotten tissue at the top of the main root with a sharp knife before planting, then spray the wound with Sukeling, and plant it after drying.

(4) after a week of planting, the medium in the basin dries gradually, the healing tissue has been formed, and the new root has begun to grow. It is advisable to spray the smooth rod of the wealth tree with pluck, Anke or zinc and manganese (Redomir-manganese zinc) to flow into the basin soil along the pole. Since then, fungicides have been rotated once a week with Anke, carbendazim, Redomir or carbendazim.

(5) if Pythium is active, it should be sprayed with Pulek, carbendazim, Redomir or Phytophthorin, and the general effect is about two weeks. If the weather is still bad, different chemicals should be sprayed to prevent the development of drug resistance. If festering plants are found during this period, they should be discarded immediately.

Leaf blight

Prevention and cure method

(1) remove the diseased leaves in time and destroy them

(2) the maintenance and management of rich trees should be strengthened in the process of cultivation, timely watering and fertilization, and foliar fertilizer can be applied for 2-3 times in each growing season, such as 0.5% potassium dihydrogen phosphate or 200 times of double-effect micro-fertilizer.

(3) before the seedlings are transported from the south to the north, protective fungicides are sprayed on the leaves, such as 70% chlorothalonil 800 times, or 18% multi-fungus copper milk powder 200 times, or 50% bacillus 600 times. After being transported to the north, it should be planted in time, strengthen fertilizer and water management, and prevent dehydration and de-fatting. Starting from the rainy season, the cultivation of rich trees in the south can be sprayed with 50% carbendazim every 10-15 days, or 70% chlorothalonil and 1500 times methyl thiophanate.

Insect pest

The main pest of the rich tree is the sugarcane flat moth, which is a new record in China, mainly because the larvae harm the rich tree, as well as poinsettia, flutung, goose palm wood and Hawaiian coconut.

What if the leaves of the rich tree turn yellow? Prevention and treatment of yellowing leaves of rich trees

Many people like to plant wealth trees, but do you know the solution to the yellowing leaves of wealth trees? Next, the editor will introduce to you in detail the solution to the yellowing of the leaves of the wealth tree to help you better plant the wealth tree.

The reason why the leaves of the rich tree turn yellow:

1. Excessive watering, no fertilization for a long time or changing pots and changing water cause the lack of nutrient elements, which leads to the yellowing of the leaves of the rich tree, so as long as the timely change of water and fertilization can be effectively avoided.

two。 If the rich tree fertilizes too much, it will cause the leaves of the rich tree to turn yellow, so stop fertilization in time and increase the amount of water, which can reduce the yellowing of the leaves of the rich tree.

3. Hot and high-temperature rich trees should not be placed in the high temperature in direct sunlight, otherwise the leaves of the rich trees will turn yellow, so when this happens, the rich trees should be moved to a cool place in time.

4. Excessive shading can also cause the leaves of the rich tree to turn yellow, so it is best to place it in a sunny and non-irritating environment.

5. If there is a lack of soluble iron and other elements that can be absorbed by the rich tree, the leaves of the rich tree will turn yellow, so acidic soil and water should be selected when planting, and alum fertilizer is often watered during the growth period.

6. Ventilation if the space where the rich tree is placed is not ventilated, too much nitrogen fertilizer is applied, the leaves are very luxuriant, and the leaves are not pruned for a long time, and insufficient light will cause the leaves to turn yellow, so it is necessary to apply reasonable fertilizer to strengthen pruning and maintain good light transmittance.

If the temperature is too low in winter, the flower leaves will dry up and turn yellow, so we must control the temperature in time to keep the rich trees growing better.

8. The leaf spot disease of the rich tree will cause the leaves of the rich tree to turn yellow and fall off seriously, so we must control the disease of the rich tree in time and control it in time.