What s the matter with the leaves of green plants that look dirty?

Coal sludge disease, also known as soot disease, is common on flowers and trees, affecting photosynthesis, reducing ornamental value and economic value, and even causing death. It can harm citrus, crape myrtle, peony, and privet.

As well as camellia, osmanthus, chrysanthemum and other flowers.

1. Symptoms

It mainly harms almost all crops such as grain, vegetables, fruit trees, flowers, gardens, etc., and has the characteristics of difficult to prevent and easy to prevent.

Occurs on shoots, leaves, and fruits. In the early stages of the disease, small dark brown punctate mold spots appear on the surface, and then continue to expand into a villous black or gray-black mold layer. In the later stage, there are many small black dots or bristle-like protrusions scattered on the mold layer.

Symptoms vary depending on the type of pathogen. The coal seam of the genus Coalsis is black and paper-like, which is easy to tear off and fall off naturally; The coal seam of the genus Thorn Shield is like ash at the bottom of the pot.

It can fall off when rubbed by hand, and it mostly occurs on the leaf surface; The mold layer of the genus is radial, black or dark brown small mold spots, scattered on the front and back of the leaves and on the surface of the fruit. Mold can be connected into large mold spots, hyphae.

Producing cells, which can adhere to the surface of the host and are not easily detached.

Second, the incidence of the disease

1. Environmental conditions:

When the outside temperature is above 10 and below 35, the external environment is humid, the area is rainy, or the high temperature and humidity in the facility greenhouse are easy to induce coal pollution disease. Poor cultivation, impermeable wind, dampness in the orchard, more dew, and high humidity in the local small environment are conducive to the occurrence of this disease.

2. Direct infection of germs:

The pathogenic bacteria will be dormant on fruit trees, flowers and branches, and the pathogenic bacteria of vegetables and grains are mostly dormant in the uncleared plant residues or soil, and when the conditions are suitable, wind and rain will become the spreaders of pathogenic bacteria, and the pathogens will directly lead to crop coal stain disease.

3. Honeydew pests and whitefly infestation:

Honeydew pests refer to the pests that will secrete honeydew when invading crop plants, honeydew mostly carries fungal diseases, viral diseases, and carries two main pests that spread coal pollution disease or pathogenic bacteria, aphids and scale insects.

are common pests of crops. Whiteflies inject coal pollution pathogens directly into crops when they suck plant sap. These three pests are the main causes of coal stain disease.

Agricultural control. Reasonable fertilization to cultivate strong plants:

Economic benefits. Higher crops should be increased with organic fertilizer, and all crops should control the application of nitrogen fertilizer, and increase phosphorus fertilizer and potassium fertilizer.

The dosage of cultivating strong plants can enhance disease resistance.

Reasonable dense planting, moderate pruning:

Fruit trees, gardens, flowers and plants should not be planted too densely, pruned appropriately, so that the park is well ventilated and transmitted, so as to reduce humidity, and avoid damp and stuffy environment.

Timely garden clearing: During the crop growth period, timely weeding and garden clearing can help reduce the incidence of pests and diseases. After the end of the planting cycle, removing dead branches, diseased fruits and rotten leaves in the plantation park can not only reduce the number of pests in the next year, but also reduce the pathogenic bacteria of coal pollution disease, so as to prepare for the prevention and control in the next year.

It may be that the green plant has aphid or whitefly disease. These insects will secrete some mucus, and eventually the leaves will become dirty, so you can buy insecticides.

First of all, most likely, the most common is dust. The leaves of green plants need to be gently wiped with a clean and soft rag dipped in water, so that they will grow better, because they can breathe fresh air in time, and then they will look more beautiful, green, and give people a sense of vitality.

First of all, most likely, the most common is dust. Whether the green plant is placed indoors or outdoors, there will definitely be dust after a long time, and the dust on the leaves is not only unsightly, but also hinders the photosynthesis of the leaves, which is not conducive to nutrient accumulation. We can wipe it with a damp cloth or spray it with a high-pressure water gun to clean the dust off the leaves.

In addition, if the leaves look dirty, it may also be due to fungal infestation, which causes mold, powder, rust and other symptoms on the leaves, making the leaves look dirty. If this is the case, it is necessary to use fungicide spray to prevent and control it immediately. What kind of disease you need to judge is the only one you need, but no matter what the disease, you can use some broad-spectrum fungicides.

This is not particularly enough nutrients, at this time to give them nutrients, and also to disinfect his leaves with alcohol, can give them nutrients, so that their leaves become more green.

The leaves can be washed with a damp cloth or pressurized with a pressed water bottle to rinse the dust off the leaves.

Leaves are mainly organs for photosynthesis and contain a lot of chlorophyll, which does not absorb much green light, so the leaves appear green.

Plants can't move and can only let insects help pollinate, while insects prefer brightly colored flowers, so this is the result of survival needs to evolve.

The green color of plants is mainly composed of chlorophyll, which keeps trees alive and grows, and makes new trees grow on the ground – and they don't have to eat any other creatures, because chlorophyll can do anything else that no other color can't: it turns sunlight into electricity, and then pure air and water into sugar. Chemists call this magic "photosynthesis."

These greens then combine this sugar with other nutrients they draw from the ground and cause it to grow new leaves, flowers and fruits.

The leaves of plants, especially green flowering plants, contain various pigments, among which chlorophyll, lutein, carotenoids, etc. are the most common, and the chlorophyll content is the highest.

Visible light (white light) is a composite of seven monochromatic lights, visible light shines on an opaque object, and the light reflected by it will show whatever color the object displays. Since chlorophyll does not absorb the green light in visible light (sunlight), all other light is absorbed, and as a result, only when the green light is reflected into the human eye, the optic nerve of the human person will transmit this information to the brain, and the person will perceive the leaf as green.

There are two types of chlorophyll: chlorophyll a and chlorophyll b, a is blue-green and b is yellow-green. In general, only the adult leaves are dark green, and the young leaves are yellow-green because they contain less chlorophyll; Old or falling leaves are also yellow-green or yellow due to the increased lutein and carotenoid content.

In autumn, the maple leaves are bright red due to the high content of anthocyanins.

The back of the leaves of the plant is dirty:

1. If it is raining, the lower part of the watering dripping will be more, and it will gradually decrease upward, which is easier to judge.

2. The possibility of pests and diseases is relatively large, especially insect pests often occur on the back of leaves, such as red spiders, scale insects, aphids, etc.

If you splash mud from the rain, just spray it with water.

The stomata of the leaves of the plant are mostly in the back.