What is the reason for the yellow leaves of poplar seedlings and the dry edges of the leaves??

First, the selection of nursery enclosure and land preparation nursery land should choose fertile, moist, well-drained soil. Before cuttings, the nursery land must be leveled and fine, so as to avoid drought at high places and water accumulation at low places during irrigation.

2. Cuttings are about 15 cm long, and there should be a bud 1 cm from the top.

3. Cuttings Dig a 1-meter-deep soil pit, soak the cuttings after filling them, and add water after water infiltration. The soaking of cuttings in water can not only make them absorb enough water, but also dissolve the rooting inhibitors on the cuttings, which has a significant effect on improving the survival rate of cuttings. It is particularly important to soak the seeds transferred from other places, and the immersion time should be 24 hours.

Fourth, the cutting time can be cut after the soil thaws in spring. Timely and early insertion is beneficial to improve the survival rate.

Fifth, the cutting method of the cuttings straight into the seedbed. Do not turn the cuttings upside down when cuttings. Irrigation immediately after cuttings to make the cuttings tightly bound to the soil and make the cuttings absorb enough water.

6. Cutting density Poplar cuttings per mu is about 4,000 plants, and the plant and row spacing can be determined according to the nursery cultivation method. If you want to grow two-year-old seedlings, the cutting density can be determined by yourself.

7. Parenting management (1) Irrigation. After the poplar cuttings sprout, the initial growth is maintained by the nutrients contained in the cuttings themselves and the permanent content absorbed from the soil. Seedlings should ensure moisture during the rooting period**.

b) Wipe the buds. When a seedling grows side branches, it needs to be wiped with buds. When the side branches are tender, they should be removed directly by hand, and if they have been lignified, they need to be pruned.

The first bud wiping should be late, generally starting when the seedlings are 40 cm high. (3) Top dressing. The nursery applies about 50 kg of urea per mu per year, and a certain amount of phosphate and potassium fertilizer can be added according to soil conditions.

Top dressing can be done in late May, mid-June and mid-July.

Water deficiency is caused by the bottom to the top of the leaves dry yellow and fall off, the lower leaf edge is dry is potassium deficiency, the old leaves are yellow tip drops, the new leaves are hypertrophied, convex and uneven, is hypertrophied.

What causes the yellowing of poplar sapling leaves? The onset symptoms of poplar yellow leaf disease are: the young leaves at the top of the branches appear first, followed by the whole leaves.

The mesophyll of the diseased leaf is light green, yellow-green or yellowish-white, and the veins are milky white. The middle lobes on both sides of the veins are still green, showing a green reticulate structure. As the symptoms worsen, the green color on both sides of the veins will gradually fade and disappear, giving the entire leaf a yellowish-white color.

Diseased leaves become smaller and thicker. The leaf margins of some diseased plants will also be scorched and curled, and finally the whole leaf will be scorched and peeled off. The chlorophyll content, net photosynthetic rate and transpiration rate of diseased leaves decreased sharply.

The internodes of the branches are short, the growth is small, and in severe cases, it can cause the death of some branches and the whole plant.

<> investigations and experiments have proved that soil nutrient deficiency (absolute deficiency) and iron deficiency (reactive iron deficiency) are the direct cause of poplar yellow leaf disease. The long-term application of livestock and poultry manure in livestock and poultry farms leads to an increase in available phosphorus, copper, zinc and manganese in the soil, and the pollution of phosphorus and heavy metals in the soil (relative deficiency) is the main cause of poplar yellow leaf disease. Soil is the root cause of poplar yellow leaf disease.

Poplar yellow leaf disease is a non-communicable disease, a physiological disease of iron deficiency, and the physiological metabolism of plants is unbalanced. Once the disease occurs, the leaves cannot synthesize chlorophyll, causing the leaves to lose green and photosynthesis cannot be carried out; Then, due to the lack of nutrients (a product of photosynthesis) in the roots, the physiological activity gradually weakens, and the plant grows slowly until it dies.

The occurrence and distribution characteristics of yellow leaf disease, the uniformity and consistency of the distribution of diseased plants: on poplars, once discovered, poplar yellow leaf disease often occurs in one or more rows at the same time, and there are scattered plants, or multiple rows occur at the same time, and the degree of incidence is very consistent between plants, and there is no process of institutional transfer or gradual spread from the disease center to the surrounding when it is found in a growing season. The development of symptoms is characterized by uniformity and consistency:

The severity of the disease may range from mild to severe, but the development of symptoms is basically the same, and the disease development is basically the same between different plants and different diseased leaves of the same plant in the same forest area. The occurrence of the disease is sudden: in many places, yellow leaf disease was not found in the previous year, and a large area of yellow leaf disease appeared in the second year, especially in nurseries.

The symptoms have the phenomenon of natural recovery and are not contagious: the survey found that some seriously ill trees, without taking any measures, returned to normal in the second year, and after returning to normal, the symptoms of yellow leaf disease did not occur again for many years, and the experiment proved that poplar yellow leaf disease is not contagious. This phenomenon is consistent with the characteristics of noncommunicable diseases.

Forestry and management practices have an important impact on the occurrence of poplar yellow leaf disease: in the survey, it was found that when the same forest belonged to different households, one or several households often had poplar yellow leaf disease, while other adjacent farmers had mild or no poplar yellow leaf disease incidence. Further investigation found that there were great differences in afforestation patterns or management measures among different farmers.

Poplar trees that have suffered natural disasters or man-made damage in the past are more severe.

This phenomenon may be caused by a lack of nutrients or trace elements required by poplars in the soil, or because the local temperature is not enough and photosynthesis is not enough.

It may be caused by a lack of nutrition, or it may be caused by a lack of light, and there are many reasons for this situation, which should be determined according to the actual situation.

It may be that the nutrients in the soil are relatively small, and the seedlings are not able to better absorb some nutrients, so the leaves will turn yellow.

Summary. Hello, there are various reasons for poplar leaves to turn yellow and wilt, here are some possible factors:1

Water scarcity: Poplars need adequate water to maintain their growth and health. If the soil is too dry, the poplar leaves may turn yellow and wilt.

2.Nutrient deficiencies: Poplars need proper nutrition to keep them healthy.

If the soil lacks essential nutrients such as nitrogen, phosphorus, potassium, etc., the leaves of poplars may turn yellow and wilt. 3.Pests and diseases:

Poplars can be attacked by a variety of viruses, bacteria, fungi, and insects that can cause poplar leaves to turn yellow and wilt. 4.Environmental factors:

Yellowing and wilting of poplar leaves can also be caused by environmental factors such as climate change, soil pollution, and lack of sunlight. If your poplar leaves turn yellow and wilt, it is recommended that you check the above factors to find out what the problem is and take appropriate steps to fix it. Hope mine is helpful to you<>

<> what causes the yellowing and wilting of the leaves of poplar trees.

Hello, there are various reasons for poplar leaves to turn yellow and wilt, here are some possible factors:1Water shortage:

Poplars need plenty of water to maintain their growth and health. If the soil is too dry, the poplar leaves may turn yellow and wilt. 2.

Nutrient deficiencies: Poplars need proper nutrition to keep them healthy. If the soil lacks essential nutrients such as nitrogen, phosphorus, potassium, etc., the leaves of poplars may turn yellow and wilt.

3.Pests and diseases: Poplars can be attacked by a variety of viruses, bacteria, fungi, and insects that can cause the poplar leaves to turn yellow and wilt.

4.Environmental factors: Yellowing and wilting of poplar leaves can also be caused by environmental factors such as climate change, soil pollution, and lack of light.

If your poplar leaves turn yellow and wilt, it is recommended that you check the above factors to find out what the problem is and take appropriate measures to fix the problem. Hope mine is helpful to you<>

<> poplar tree got the medicine that killed the tree two months ago, and then it was alive and well, and now it has grown leaves, and in the past two days, the leaves have withered, and the hail socks have wilted and widened, does it have anything to do with this medicine?

Hello, yes, there is a relationship. The poplar tree was masked because it had been treated with drugs two months ago, which affected the growth and metabolism of the internal panicle of the tree, and eventually caused the leaves to wilt. It is recommended that you ask a professional horticulturist or botanist to come for examination in time and give corresponding ** and care.

At the same time, in the future plant care, it is necessary to avoid the use of inappropriate or excessive drugs to protect the health of the plant.

1. Boxwood stem base rot.

In the investigation, it was found that boxwood stem base rot did not attract the attention of gardeners, and was always ignored, because the initial stage of the disease was mainly manifested as individual dry branches and dead leaves that were easily mistaken for drought or not completely transplanted to survive, so many times they were allowed to develop, and the best prevention and control period was missed, so that the disease spread more and more in the later stage, and finally a large number of boxwood plants dried up and yellowed and died.

2. Harm plants.

Through long-term investigation and analysis in many places, it was found that boxwood stem base rot not only harmed large-leaved boxwood, but also harmed holly plants such as melon seed boxwood, Phnom Penh boxwood, and bird's-tongue boxwood.

3. Causes of the disease.

High temperature and humidity are external environmental factors for the occurrence of diseases. The fungus is the causative agent of the disease, the pathogen mainly lives in the soil, with the increase of soil temperature, the fungus begins to infect the rhizome parts of seedlings, especially in the high temperature and low-lying areas.

4. Symptoms of harm.

Large-leaved boxwood stem base rot is the main hazard.

The incidence of first- and second-year-old shoots and newly transplanted boxwood seedlings is also higher. In the early stage, the stem of boxwood turned brown, and in the later stage, the damaged part of the stem base turned black, and the cortex shrank, and the xylem color was brown after the cortex was peeled off, and the xylem was gradually deepened from the outside to the inside by transverse incision, and the pith became black in severe cases. With the increase of temperature, the damaged part develops rapidly, the germ invades the xylem, the color of the xylem first changes from brown to black, and the germ invades the xylem, resulting in the death of the whole plant.

5. Prevention and control methods.

1.Strengthen the maintenance and management of seedlings, and drain low-lying places in time to prevent the occurrence of diseases induced by high humidity.

2.In summer, small seedlings should be shaded or planted under large trees to achieve the purpose of cooling.

3.Pharmaceutical prevention and control. When diseased plants are found in the nursery or in the green belt, clean them up in time, and use fungicides such as carbendazim and dimethazim to irrigate the roots, or you can choose a special fungicide to water the roots of Lane Ping'an Yuyuan 1-15 times, or adjust the nozzle of the sprayer to the direct spray mode, and spray it on the rhizome part, which must be sprayed evenly and thoroughly.

6. Summarize that high temperature and high humidity are the external factors that induce the outbreak of the disease, we should pay attention to creating appropriate temperature and humidity to reduce the occurrence of the disease in our daily maintenance work, spray fungicides before the arrival of the high temperature and high humidity season, do a good job of prevention, and observe and deal with the disease in time to minimize the harm of the disease.

The yellowing of the leaves of the poplar tree is the yellowing of the seedling.

There are generally only a few reasons for this:

1. Stagnant water. Long-term water accumulation at the roots of poplar trees leads to such a situation, and it is enough to make drainage ditches in the field.

2. Fertilizer and burn seedlings. When fertilizing the water, it did not keep up in time. In such a situation, after the rain, I will slowly get better.

3. Pest and disease hazards. Mainly leaf mites, spraying drugs to kill red spiders can be done.

Methods for the prevention and control of leaf spot, rust, scab, downy mildew and other diseases of jujube, apple, pear and other fruit trees:

At the beginning of the disease, spray 800 times 80% mancozeb wettable powder (Aino Aisheng) + 1000 times "Tianda 2116" (special type for fruit trees), 1 time every 10-15 days, 2-3 times in a row, pay attention to alternate use with Bordeaux liquid.

Usually apply water-soluble fertilizer to enhance resistance.

If the leaves of poplars are yellow, if they are infected with yellowing, they can be sprayed with ferrous sulfate and urea solution**.

The soil is not fertile enough to cause the poplar leaves to turn yellow, you can supplement some iron-rich organic fertilizers to make the poplar leaves more green, and at the same time, you can also add a certain quality of ferrous sulfate to the soil, so that the soil has more nutrients, and effectively prevent and control the yellow leaf disease of poplars.

Send a ** to see, this description is too general.

Hello dear, most of them are caused by improper water and fertilizer or environmental factors. 1.In general, if the leaves of the boxwood tree are dry, it can be saved, and as long as the roots do not wither, the boxwood tree can still live.

At this time, we need to find the cause of the dry leaves of the boxwood tree first, and then treat the symptoms according to different reasons. 2.If the root system of the boxwood tree dies, the boxwood will gradually dry up because the leaves absorb the waste and lack nutrients.

3.Overwatering: If the boxwood is overwatered, it will cause the boxwood leaves to turn yellow, which is characterized by the fact that the old leaves of the boxwood do not change significantly, but the newly grown leaves will turn yellow.

At this time, the solution is very simple, that is, you need to control the moisture. 4.Too little watering:

If the boxwood leaves turn yellow from the bottom up, it may be caused by a lack of water. If the water shortage is too long, it can even lead to the death of the whole plant. The solution to this situation is the need for timely watering.

5.Nutrient insufficiency: Insufficient nutrients in boxwood can also lead to yellow leaves, and if this is the case, then the young leaves and young stems of boxwood will turn yellow first.

When this happens, it is necessary to apply fertilizer in time, but it is necessary to pay attention to thin fertilizer and frequent application, so as not to cause root burning. I hope mine can help you. I hope mine can help you.