What s the deal with the poplar leaves with a lot of yellow powder spots on them?

Hello. Symptom characteristics].

Yellow powder on poplar leaves.

It is a symptom of poplar leaf rust.

At the beginning of the disease, orange punctate spots are produced on the back of the leaves, and the epidermis is broken to reveal orange powder, which is the summer spore pile. In autumn, brown winter spore piles are produced on the front of the leaves and the corresponding places of the summer spore pile, and when the disease is severe, the back of the leaves is covered with yellow powder, which affects photosynthesis.

It also causes defoliation due to leaf water loss. The host host of poplar leaf rust is larch. Winter spores of poplar leaf rust overwinter on diseased leaf litter.

In the spring of the following year, the spores germinate to produce basidiospores, which are spread to poplar microphylla by the wind, and invade by the stomata, producing summer spore piles. Summer spores repeatedly infected poplar trees, and the onset of the disease was most important in autumn. Rinnai.

The humidity is high and the young forests are densely planted, which is conducive to the occurrence and epidemic of diseases.

Control method] in poplar forest.

Larch is not planted nearby, and overwintering diseased leaves are removed or treated. During the onset period, it can be prevented and treated with pesticides, spraying Baumé.

Lime sulfur mixture, or 50% rust 200 times solution, sodium rust 200 times, 65% zeb 500 times solution, 20% powder rust 2000 4000 times solution.

Management of poplars.

5. Poplar cultivation and management technology.

1. Watering and fertilizing.

For large trees, the adaptability is very strong, so the number of fertilization can not be too much, to avoid affecting the growth and development of poplars, if you want to fertilize, it is best to apply fertilizer once in autumn and winter. In the process of fertilization, you should not simply sprinkle the fertilizer on the surface of the tree, you should dig a few small pits around the tree and sprinkle the fertilizer into the pit, so that the fertilizer can penetrate into the roots and improve the growth ability of the poplar. It is recommended to use water-soluble fertilizer with large elements of Fuwo Swoye granules, which is convenient, labor-saving and time-saving, and has a quick effect.

2. Weeding and loosening the soil.

In the process of poplar growth, the staff not only has to clean up the weeds, but also loosen the soil, so that the poplar can better respirate.

Roots can better absorb nutrients and water, and increase the vitality of roots.

3. Prune branches.

When there are many branches, it is necessary to repair them in time, and when repairing the branches, it should be repaired at about 30 cm of the predetermined incision. In the process of repair, the poplar tree should be protected, and the bark should not be damaged, otherwise the quality of the poplar tree will be affected.

4. Prevention and control of pests and diseases.

The leaf-eating insect pests of poplar mainly include willow poison moth, poplar fan boat moth, poplar boat moth, poplar boat moth and so on.

Poplar.

If the nutrients of the roots of the tree are insufficient, the water is not sufficient, in addition, the sun is too sufficient, this situation will occur, so first of all, you should let him be more fully nourished, give him some nutrients appropriately, in addition, the time of light is not too long, it will be better to delay for a while.

Poplar leaves turn yellow, mainly to adapt to unfavorable growing conditions in winter. Generally, in late autumn and early winter, poplars, willows and other deciduous tree species will have yellow leaves and fall off; Yellowing and defoliation of plant leaves in winter is an adaptation of plants to the dry and cold environment in winter, and new leaves can germinate after the temperature warms up in the following spring.

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

Because the soil is not fertile enough and lacks the necessary nutrients, it can also cause the poplar leaves to turn yellow.

Summary. What's the deal with the poplar leaves with a lot of yellow powder spots on them? Hello!

Poplar rust is one of the main diseases affecting young poplars and seedlings, and poplar leaf rust, also known as powdery mildew, mainly damages leaves, petioles, shoots and winter buds. Orange-yellow powdery spots appeared on the affected leaves in the early stage, and the yellow powder (summer spores) increased day by day, becoming the pathogenic center of reinfection. Summer spores are spread by wind, and then infect new leaves The most serious is in the month, and the leaf lesions are connected into patches, often causing scorched leaves and defoliation.

After the winter buds are damaged, they cannot spread their leaves or shrink and thicken, and they roll up to the back of the leaves. Petioles and young shoots are damaged to form strip-like lesions. The onset of the disease is mild in the rainy season, and the second peak of the disease enters in August and September.

Nurseries are susceptible to the disease. Prevention and control methods of poplar rust 25% powder rust is preferred to be sprayed with wettable powder 1000 to 15000 times; 65% zebsen 500 times solution; Spray 200 times dilugent sodium and spray once every 15 days; At the onset of the disease, spray 1 1 125 170 Bordeaux solution once, and then use Baumé stone sulfur mixture to prevent and control.

What's the deal with the poplar leaves with a lot of yellow powder spots on them? Hello! Poplar rust is one of the main diseases that affect young spike trees and seedlings of poplar trees, and poplar leaf rust, also known as powdery mildew, mainly damages leaves, petioles, shoots and winter buds.

Orange-yellow powdery spots appeared on the affected leaves in the early stage, and the yellow powder (summer spores) increased day by day, becoming the pathogenic center of reinfection. Summer spores are spread by wind, and the new leaves are most seriously infected, and the leaf lesions are connected into patches, often causing scorched leaves and defoliation. After the winter buds are damaged, they cannot spread their leaves or shrink and thicken, and they roll up to the back of the leaves.

The petioles and young shoots are damaged to form strip-shaped sedan spots. The onset of the disease is mild in the rainy season, and the second peak of the disease enters in August and September. Nurseries are susceptible to the disease.

Prevention and control methods of poplar rust 25% powder rust is preferred to be sprayed with wettable powder 1000 to 15000 times; 65% zebsen 500 times solution; Spray 200 times dilugent sodium and spray once every 15 days; At the onset of the disease, spray 1 1 125 170 Bordeaux solution once, and then use Baumé stone sulfur mixture to prevent and control.

Will it recover naturally in the coming year?

Hello, dear, after the end of the fallen leaves, you can recover when you give birth to new leaves in the next year, dear, it is recommended to pro, it is best to do a good job of prevention and control methods, dear.

1. Pathogen. The pathogenic bacteria were Basidiomycetes subphylum Pyromycetes, Horse Grating Rust and Poplar Rust of the genus Schizomycetes. Summer spores are yellow and scattered or clustered.

Summer spores are round or oval, can be orange-yellow, with spiny protrusions on the surface, 21 30 m in diameter. Winter spore spindle cylindrical, brown, size 37 50 10 15 m. The transfective host of the bacterium is not known in China.

2. Pathogenesis.

The pathogen overwinters with hyphae in canker spots on winter buds and shoots. When poplar trees sprout, the hyphae develop to form summer spore piles, which become the primary source of infection of the year. After the germination of the spores of the fungus, they can directly penetrate the stratum corneum and invade by wind.

The optimal temperature for summer spore germination is 15 20. The planting density is too large, the temperature is high, the rainfall is more than one trillion acres, the humidity is high, the ventilation and light transmission are poor, and the seedlings and young trees are susceptible to diseases.

3. Prevention and control methods.

1) Remove diseased buds in early spring. Care must be taken to avoid scattering the spores during operation, otherwise the desired effect will not be achieved.

2) Breeding strains with strong disease resistance, breeding imitation seedlings or afforestation.

3) pesticide prevention and control: spraying 600-800 times the liquid in the early stage of leaf disease, spraying powder rustazole for prevention and control, using 2-3 times in a row, with an interval of 15 days, the dosage can be appropriately increased during the high incidence period of the disease, and the compound use of broken bacteria in the severe period is more significant.