How to prevent walnut rot? 10

It is caused by one of the more common diseases of walnuts, that is, anthrax, so everyone knows why walnuts rot fruit.

Dangers of anthrax to walnuts:

Walnut anthracnose generally begins to show symptoms of fruit damage after July 20 each year. After the walnut fruit is damaged, brown to black-brown, round or near-round lesions will appear on the peel, ** concave, and there are small black dots on the diseased part, sometimes arranged in a wheel-like arrangement. When the humidity is high, the small spots appear as pink protrusions, that is, the conidia disc and conidia of the pathogen.

When walnut is seriously ill, a diseased fruit often has multiple lesions, and the lesions expand and become patchy, resulting in the whole fruit turning black and rotting to the endocarp, and the kernel has no edible value.

When the onset of anthrax is mild, the outer skin of the nucleus shell or nucleol becomes black, which reduces the oil yield and kernel yield, or the lesion is confined to the exocarp when the fruit is ripe, which has little effect on walnut. After the leaf is susceptible, the lesions are irregular, some are yellow along the edge 1 cm, and some are long strips on both sides of the main vein. In severe cases, the whole leaf is yellow and falls off.

The buds and shoots of seedlings and young trees often wither from the top downwards after being susceptible to the disease, and the leaves fall off in a charred form.

Prevention and control methods of rotten fruit caused by walnut anthracnose:

Method. 1. Timely disease stiff fruits and diseased branches and leaves, concentrated burning, reduce the incidence of disease.

Method. 2. Strengthen management, reasonable fertilization, pay attention to increasing the application of organic water-soluble fertilizer, strengthen pruning, and improve the ventilation and light transmission conditions in the park, so as to facilitate the control of diseases.

Method. 3. Remove the diseased fruit in time when it is found, and spray 2-3 times 80% tebuconazole 4000 times, 10% difenoconazole 3000 times, and 80% mancozeb 800 times. Method.

4. If the walnut orchard is seriously ill, it can be sprayed with 500 times of 2% ningnanmycin, and alternately used with 3000 times of 10% difenoconazole. Generally, 600 times of copper acetate is sprayed before germination, and the above-mentioned agents are sprayed before the onset of flowering, and the control effect is better.

1. Remove diseased fruits and diseased branches and leaves in time, and burn them intensively to reduce the incidence of disease.

2. Strengthen management, reasonable fertilization, pay attention to increasing the application of organic fertilizer and bacterial fertilizer, strengthen pruning work, and improve the ventilation and light transmission conditions in the park, so as to help control the occurrence of diseases.

Hand fungicides for anthrax are sprayed with amino acid foliar fertilizers.

To prevent fruit drop, it is necessary to strengthen tree management, improve soil, strengthen cultivation and weeding, increase organic fertilizer, and maintain tree health. Prune reasonably, adjust the tree potential, pay attention to appropriately expand the row spacing, so that the garden and the canopy are ventilated and light-transmitting, and the disease is reduced.

Carefully remove diseased branches and leaves and diseased fruits at the time of onset. Concentrated deep burial or destruction. Reduce the stock of pathogens in the next year, after flowering, young fruit stage, spray 1:

1: 200 times Bordeaux liquid; Or spray Baumé 3 5 degree stone sulfur mixture before budding for prevention.

In order to reduce the occurrence of diseases in walnut tree fruits, it is necessary to adopt comprehensive control methods, apply more farm fertilizer and organic fertilizer, and improve the disease resistance of the tree. Improve the premise of tree ventilation and light transmission. Prevention is the priority, and the diseased branches are found to be treated in real time, and drugs are actively sprayed for prevention and control.

so as not to expand the area of infection. Minimize losses.

Precautions for walnut planting.

Walnut tree planting generally dig a pit in about 45 cm square, that is, the diameter of the pit is 45 cm, the depth is 45 cm, if the soil layer is thin or there are many stones, you can dig a big pit, more backfill more soil, soft soil is more conducive to seedlings to take root.

Walnuts love sunlight and need plenty of sunlight when they enter the fruiting period. During the growth period, it has a great influence on the growth of the tree, the differentiation of flower buds, and the fruiting of flowering.

The walnut is unripe and turns black and falls, which is walnut black rot.

The symptoms are mainly fruit damage. The fruit is infected in the early stage, and small brown spots appear on the green skin, which gradually expand into a black-brown color, and the flesh rots. The fungus can infect the kernel part, and finally the whole fruit will rot, shrink and fall off.

The fruit is infected in the later stage, and the lesion expands slowly, and due to the hardening of the endocarp, although the flesh is rotten, it is not rotten to the kernel, and it is not easy to fall off, and the loss is small. It can also infect young branches, young leaves and flowers, and the disease is in full bloom during the rainy season.

Prevention and prevention plan: Before the onset of the disease, dilute and spray according to 800 times the solution, and use the drug once every 15 days.

**Scheme: When the disease is mild, it is diluted and sprayed according to 800 times, and the drug is used once every 10-15 days; When the condition is severe, dilute it with 500 times of the liquid and spray it once every 7-10 days.

1. Breeding resistant varieties. One of the important ways to prevent and control the disease, walnut selection should take disease resistance as one of the important indicators.

2. Pharmaceutical prevention and control. The use of fungicides before or at the beginning of the disease is a relatively effective measure to prevent and treat the disease.

3. Strengthen cultivation management. Reasonable pruning when cultivating strong seedlings and trees to reduce microclimate humidity; Remove diseased leaves, fruits, and branches in time to reduce pathogens in the field.

There are two reasons for the black rot of walnut fruit: one is the harm of walnut lifting moth, which is only found in old walnut producing areas, especially in mountainous areas. This situation requires 2 sprays of pyrethroid insecticides in 6-7 months.

The second is caused by the disease, and the disease is also divided into two kinds, if it is black before mid-July, most of it is walnut black spot, if it starts in late July, especially after early August, it is walnut anthracnose. To prevent and control the above two diseases, one is to strengthen management, prevent orchard canopy, and improve the ventilation and light transmission capacity of the orchard.

the second is to spray 5 Baumé stone sulfur mixture on the whole tree before budding in spring to disinfect the whole tree; If the disease is severe, spray agricultural streptomycin + carbendazim or methyl tobuzin (for walnut black spot) in early May, and spray twice in late July to mid-August with lime multiplier Bordeaux solution, or fungicides such as methyl tobuzin (for anthracnose).

In fact, there are many reasons for walnut tree rotten fruit, but an important reason is walnut anthracnose, which mainly harms the fruit of the walnut and the leaves of the walnut, and the susceptibility rate of the fruit is 20%-40%, and it can reach more than 90% in severe cases. The infected fruit can produce 1 to 10 lesions, and the lesions may enlarge or several lesions fuse, resulting in the black rot of the whole fruit, or the shriveled kernels.

1. Exposure to the sun and high temperatures. If new walnuts and old walnuts are exposed to direct sunlight for a long time, they are very likely to crack.

Precautionary measures to minimize playing in the sun, especially new walnuts. When you're not playing, don't leave walnuts outdoors, on windowsills with sunlight, heating (in winter), balconies, etc.

2. New walnuts attract wind. The new walnuts have just peeled off the green skin, and before they are dry, they start to play with them when they are wet, and if they are outdoors, they encounter wind or indoor fans blowing the walnuts directly, and the walnuts will generally have the possibility of cracking. As a precaution, it is best not to rush to get started with the newly planted walnuts, and wait at least about a week for the walnuts to be dispersed and dry before getting started.

3. Do not dry in the shade after cleaning. New walnuts and old walnuts that I didn't get my hands on. If it needs to be cleaned, it must be dried in the shade for at least three days after cleaning, otherwise if the walnuts are not completely dried by the moisture inside and outside the walnuts, the walnuts will crack when the wind blows.

Precautionary measures, after washing, directly or first in the envelope (not sealed) in the drawer, wait for at least one round of dry for a week before starting.

4. Smash and squeeze. Sometimes walnuts inadvertently fall to the ground, and it happens to crack, walnuts are squeezed in the trouser pocket, and there are heavy objects on the walnuts when they are stored, which will cause walnuts to crack. Only by properly keeping Yu Tongbo and playing with it carefully will your beloved things not be damaged.

5.Over-ripening. There are some varieties of walnuts that have passed the picking season and have not been planted in time.

Let the walnuts continue to hang on the tree. When a walnut grows too ripe and too full, the tip of the walnut will naturally open its mouth. Such walnuts are easy to crack in the future during play.

6.Walnuts washed with acid bites are prone to cracking. Because the joints of walnuts become loose and not tight after being soaked in strong chemicals.

When playing, most walnuts will crack or the sound is wrong, walnuts after washing or acid biting, the cortex of walnuts will be damaged, and this damage is irreversible.