First, the management of soil, fertilizer and water.
(1) Soil fertilizer and water management of young and newly planted persimmons
Most young persimmon trees are 1-5-year-old trees after long-term low-temperature freezing injury from last winter to the beginning of this year. Trunk appears, especially in the root and neck, and the cortex splits longitudinally, which affects the growth of the year. Therefore, fertilizer and water management should be strengthened, especially for frozen trees. That is, after thawing in early spring, topdressing the soil in time and watering it once to promote its vegetative growth, promote the healing of its frozen parts and prevent other diseases such as persimmon witches' broom caused by freezing injury. If there is no fertilizer and water management in early spring, fertilization and irrigation should be supplemented in the middle and late May. That is, 1-3-year-old persimmon trees, each 0.25-0.5 kg; Apply 0.5- 1.0 kg special fertilizer for 4-5-year-old persimmon trees. This fertilizer can be mixed with soil and applied in pits or ditches. After application, it can be watered with enough water.
The seedlings of the newly planted saplings used for the newly planted saplings in the spring of 2003 were more or less frozen. In order to improve the survival rate of newly planted young trees and ensure the survival of frostbitten seedlings, the key is to strengthen soil moisture management, keep the soil moist for a long time, and replenish water in time until new shoots and leaves grow normally. When the new shoots grow to more than 15 cm, apply 0.20kg/ plant special fertilizer for common persimmons at the end of June to promote their full growth, and remove the plastic film covered by spring trees at the beginning of June.
(2) Fertilizer and water management of early-maturing persimmon with whole fruit
For persimmon trees with medium or strong tree potential, it is not necessary to emphasize fertilizer and water management in spring, but to carry out heavy fertilizer and water management in the middle and late July (when the fruit begins to grow rapidly). The main measures are combined with soil improvement, mainly pressing green manure (fresh weeds, etc. ), supplemented by mixed persimmon special fertilizer (high-iron or ordinary). That is, ditch on the projected edge of the crown, with a depth of about 50 cm, a width of about 50 cm and a length of 1.2- 1.5 m. Each ditch is pressed with about 50 kg of green manure and 2-3 kg of persimmon fertilizer (depending on the size of the tree). Green manure, special fertilizer and soil are fully mixed and pressed into the ditch, and the ditch surface is sealed tightly with soil. Do it once a year, and it is not advisable to ditch and fertilize too much to avoid excessive root damage. If there is no condition to apply green manure, only 2.5-3 kilograms of persimmon fertilizer can be applied per plant, and hole application can be used (no more than 5 kilograms per plant).
(3) Fertilizer and water management of old tree structural transformation
The structural transformation of tall old persimmon trees is mainly to reduce the height and adjust the skeleton. After the soil thawed in the spring of that year, the high-nitrogen persimmon special fertilizer should be applied in time (the method and dosage are the same as above), and enough water should be poured. If it is not managed in spring, it should be carried out in late May, in order to cooperate with winter cutting, promote the vigorous growth of its new branches and create conditions for the formation of COVID-19 as soon as possible.
Depending on the flower amount of the whole tree after structural adjustment, the flower amount is large, which can be carried out with reference to the fertilizer and water management measures of persimmon trees in the middle and late July of the full fruit period.
Second, summer pruning
(1) Summer Pruning of Young Persimmon Trees
Pruning persimmon trees at this age in summer is mainly to cooperate with pruning and shaping in winter, cultivate branch groups and adjust branch density and branch structure. First, adjust the direction of the main branch in May to balance the growth potential of the main branch. Young persimmon trees are prone to appear strong on the top and weak on the bottom. By adjusting the growth potential and quantity of annual branches of each backbone branch, the relationship between the upper and lower layers is balanced, and the dominant position of the first layer of main branches is guaranteed. The second is to gradually enlarge the base angle of the main branch when the base angle is too small to prevent the skin from being caught and enhance the firmness of the main branch. The bottom angle should be gradually expanded to prevent splitting caused by operation; Third, take measures such as bracing to increase the angle of the main branch from August to September, which is generally about 45 degrees (the angle can be expanded by itself after the results are produced); Fourth, before the end of May (before the flower bud differentiation in that year), the auxiliary branches (or branches or branches of the same year) of the same age as the main branches will be opened at a certain angle to promote their development into fruiting mother branches, and the back branches will be strictly controlled or loosened; Fifth, thinning out long branches, over-dense branches and buds, and erasing sprouting branches at the trunk and root neck.
(2) Pruning early-bearing persimmons in summer
Persimmon trees of this age are pruned mainly in May in summer, and pruned in winter, adjusting nutrient distribution, treating flourishing branches, removing buds and shoots, thinning out over-dense branches and cultivating branches. According to the size of the space, select, cultivate and utilize the sprouted branches near the kerf, that is, keep the crown ventilated and transparent, and not just bald. Generally, dense branches are required, and long branches are required in vain; Leave room for the branches that stopped in that year, and they can develop into fruiting branches in that year; For large and clustered branches, you can cut off 30-40 cm. If overgrowth continues, they can be cut off or continuously cored and cultured into branches.
(3) Structural transformation and pruning of old trees in summer
On the basis of pruning in winter to transform the tree structure, tall old trees adjust the nutrient distribution of trees and promote the adjustment of tree structure with pruning in summer. Among them, it mainly deals with the annual branches developed near the saw mouth of winter shears.
1. Select and keep new trunk branches: select stout long branches with strong growth potential and suitable orientation as trunk branches for cultivation, adjust the bottom angle in May to prevent splitting caused by too small bottom angle, promote elongation and thickening growth in the current year in combination with the above fertilizer and water management, and properly open the angle in August-September; This work is an important work to supplement or build a new skeleton. Generally, it is advisable to transform the structure of modest trees with tall persimmon trees. Therefore, we can choose and keep long branches according to the needs of open-minded backbone branches, and cultivate future backbone branches.
2. After re-cutting, there is still no branch growth in the part that needs to be branched, so skin grafting can be carried out in this part to cultivate the backbone branches in a targeted manner. Grafting time should be as early as possible during cambium activity.
3. Treatment of other branches in that year: For the parts with large space, after cutting off the clustered branches by 30-40 cm in May to promote their branching, the cut 1-2 buds can continue to sprout vigorous branches, and they can be thinned or cut off from the base to leave attached buds, forcing several branches with large angles to appear in that year and cultivate into a branch group. For the branches with relatively weak growth potential and not stopped growing, measures such as bending branches, pulling branches or lightly removing cores should be taken before the end of May to promote their slow growth and cultivate them into fruiting branches. For the spatial length of 15-40 cm, the stopped long branches generally do not move, but they can form fruiting mother branches in the same year.
4. Except for the above branches, all branches and buds that are too dense in the crown are erased.
5. Remove the useless branches from the root and neck of the trunk.
Three. Integrated control of main pests and diseases
From May to August, the main pests and diseases were persimmon stem borer, persimmon scale insect, persimmon caterpillar, persimmon orchard spot and angular spot.
(1) Integrated control of persimmon leaf worm:
1, spraying chemicals on the trees-spraying 25% diflubenzuron No.3 for 2,500 times 7-8 days after the early flowering period of persimmon trees (the peak emergence period of overwintering adults); Or 2500 times the sweep; Or more than 1000 times; Or 2000-2500 times of beta-cypermethrin.
2. From mid-July to early August, the drugs used to control the first generation of adults (peak eclosion) were the same as above. The key part of pesticide application is the fruit pedicle.
3. From mid-June to mid-July, manually remove and pick up dead fruits and bury them deeply.
4. At the same time, chemical control of persimmon pests was carried out on black dates.
(2) Integrated control of persimmon scale insects:
1, in early May, persimmon scales came out, and chlorpyrifos 1500-2000 times or fast scales 800- 1000 times were sprayed on the trees, which was meticulous and thoughtful.
2. In the first half of June, the first generation of eggs hatched at the peak, and the pesticide chlorpyrifos 1500-2000 times; Or 2,000-2,500 times of high-efficiency cyanogen chloride, can be used for preventing and treating key parts, branches, leaves, fruits and persimmon stems, and can also be used for treating apple leaf roller, stinkbug with tea wings, leafhoppers and the like.
(3) Integrated control of persimmon caterpillar:
1, trunk spraying at the end of March and the beginning of April; Spray the closed medicine ring on the trunk, with the height 1.2- 1.5 m and the width 15-20 cm. One dose (pyrethroid) plus 50 doses of water (or diesel oil) has a high population density. /kloc-spray again after 0/0 days.
2. In the middle and late May, the above pesticides were jointly used to control persimmon caterpillar and persimmon caterpillar.
(4) Integrated control of persimmon leaf disease and angular leaf spot.
The infection period of persimmon leaf spot is June-July, and the incubation period is 60-90 days. The infection period of persimmon angular leaf spot is from July to August, and the incubation period is 25-3 1 day. Both diseases will lead to defoliation, fruit reddening, softening and premature shedding.
Chemical control: according to the infection law of pathogenic bacteria, spray it once at the end of May, June and July, focusing on the back of leaves, with 70% mancozeb wettable powder 500 times; 80% Sheng Da wettable powder is 800 times; 75% chlorothalonil wettable powder 1000 times; Or 1: 5-6: 500-600 times lime multi-volume Bordeaux solution.
Four, persimmon management should pay attention to the problem:
(1) intercropping crops and its management:
Intercropping young trees should leave enough room for young trees to grow; Intercropping crops and persimmon have the same physiological rhythm; There are no common pests and diseases. Generally, newly planted trees have a space of 1 m (that is, the border width of persimmon trees). With the growth of tree age, the crown expands and the width of the border increases accordingly. The high growth of intercropping crops cannot affect the opening and extension of the first layer of persimmon trees, and it is not suitable to intercrop vegetables and other crops that need too much water and fertilizer in autumn.
In addition to the above requirements, persimmon trees should not be intercropped with crops that require too much potassium fertilizer, such as sweet potatoes.
(2) The transformation of ancient and famous trees should adopt the comprehensive management technology of soil, trees and diseases and pests. Special emphasis is placed on the effective management of soil, and the problem cannot be solved by single pruning. Otherwise, it is difficult to achieve the expected results.
(3) Last winter and early this year, persimmon trees were frozen for a long time, which was rare for many years, especially young trees. Emphasizing the comprehensive management in the early stage, strengthening the management of fertilizer and water, and paying attention to the application of special fertilizer are important measures to cultivate the vitality of strong trees after callus and freezing injury, and are the basis to improve the wintering ability.
(4) The heavy rainfall this spring is twice that of the same period last year, which is easy to cause large-scale infection of persimmon orchard spot and angular spot; If the control is not in place, it is easy to cause fruit shortage or no harvest in frequent areas. Therefore, the prevention and control of the above two diseases should be regarded as the focus of integrated pest control this year, and the prevention area should be expanded and the prevention and control efforts should be strengthened. While prevent persimmon diseases, it can also prevent black jujube disease.
(5) Scientific use of pesticides: 1. Choose pesticides with high efficiency, low toxicity, low residue and no pollution to protect the ecological environment and produce safe fruits; 2. Promote the staggered use of different kinds of pesticides, prevent the repeated use of a single pesticide, and prevent pests and diseases from producing drug resistance; In particular, pyrethroid pesticides should be used alternately with other types of pesticides, such as bionic preparation (chlormequat No.3). ) or ether preparation (Dolebao, etc. ); 3. To prevent the use of pesticides with high concentration and prevent environmental pollution.