Artificial treatment of pests: Pruning chestnut trees in winter, removing branches and dead branches and centralized burning can effectively reduce the base of pests and diseases in winter and reduce the harm of pests and diseases in the coming year. In early spring, according to the overwintering characteristics of pests such as chestnut aphid and chestnut gall midge, the overwintering egg pieces and female scale insects were scraped manually in time. According to the characteristics of suspended animation of adult scarab, the adult on the tree was knocked down at night and killed artificially. For chestnut orchards with more gall caused by gall wasps, artificial gall removal can be adopted to reduce the occurrence of pests.
Light trapping and killing pests: Use some phototactic pests, black light (or incandescent lamp) trapping and killing, the effect will not stop. For example, in 1998, we hung four 40W black lights in Baiyanwan Village, Lutan Town, 13.3hm2 to trap and kill the third generation adults of peach moth, and the damage rate of the third generation larvae to chestnut was reduced by 70% compared with 1997. It is also very effective to trap and kill beetles and chestnut moths with black light. This method has low cost and no pollution to the environment, and is worth popularizing. The cause of chestnut blight doesn't need spraying liquid medicine or airing in the whole garden, just scraping off diseased branches or spraying. In chestnut orchard damaged by scale insects, there is no need to dry or spray chemicals in the whole orchard, as long as there are more than 1.5 branches of female scale insects in 10 cm, which not only reduces the dosage of pesticides, but also protects natural enemies. To control the adults of scarab, it is not necessary to spray chemicals on trees and grass during the day, but to spray chemicals on trees at night when scarab is harmful to trees, which can reduce the amount of pesticides.
Spraying with a sprayer requires a nozzle, which can reduce the dosage of pesticides and make the liquid medicine sprayed evenly without waste, while using a spray gun with a spray column will lead to a large amount of liquid medicine waste. When preparing the liquid medicine, measure the original medicine with a small measuring cylinder. Rough pouring is not allowed, which wastes the original medicine, especially the high-priced medicine. Should be prepared as needed. It is not allowed to dilute a large amount of liquid medicine after mixing with mother liquor, which will lead to excessive preparation at night and waste.
When the number of pests reaches the control index, reapplication can reduce the frequency of application. When the liquid medicine is prepared at a low concentration, it is not necessary to prepare at a high concentration. For example, when 50% parathion EC or 40% omethoate EC is 65,438+0,000 times, it can effectively control pests such as beetle adults, chestnut aphid eggs and nymphs, chestnut nymph, chestnut moth and moth larvae, and is not suitable for preparation. Prevention first: when pests and diseases are inactive and show symptoms, they should be used in the early stage in time, which can prevent the occurrence of pests and diseases and effectively control the development and spread of pests and diseases, such as chestnut blight, chestnut anthracnose, chestnut scale insect and chestnut aphid. Before germination in winter and early spring, the whole garden should be sprayed with 1 3-5 degrees stone sulfur mixture and 0.3% pentachlorophenol mixture. In addition, deep ploughing in winter can also eliminate overwintering pests.
Prevention and control should be fast: pest control in chestnut orchard should be unified in the shortest time and completed at one time, making it difficult for pests and diseases to breathe and escape. The rapid elimination of pests and diseases that have occurred can reduce the number of insect populations and the source of disease, making it difficult for pests and diseases to produce drug resistance. You must not control it every once in a while, so the effect will be poor. It is worth noting that the same concentration of pesticides should be used at the same time to avoid the spread of pests and diseases in non-spraying areas to spraying areas and the invasion of pests and diseases in low-concentration spraying areas to high-concentration prevention and control areas.
Prevention and control should be accurate: pests have incubation period, emergence period and peak period, and prevention and control at peak period can get twice the result with half the effort. The overwintering larvae of scarab were unearthed in late May. At this time, spraying 50% phoxim EC on the ground for 300 times can inhibit the number of emerging adults. Or in mid-June, spraying pesticides at the peak of scarab damage can also greatly reduce the number of pests. Mid-June is the peak of adult emergence in Chestnut Peak, and prevention and control at this time can reduce the number of galls in the coming year. The first ten days of June and the middle and late days of July are the peak periods of the fruit-eating pest Spodoptera exigua 1 generation and the second generation larvae. At this time, spraying 1000 times of 50% parathion EC can effectively kill eggs and larvae. The first half of September is the peak of the third generation larvae of peach fruit borer. Using dichlorvos with short duration or high efficiency and low toxicity has good control effect, which can prevent the fruits to be harvested from being affected by pesticide residues and endangering human health.
Selection of drugs: the mouthparts of pests are different, such as chewing, pricking and licking. Stomach medicine is used to control chewing mouthparts pests, but it is ineffective for sucking mouthparts pests. For example, chewing mouthparts pests such as scarabs and grubs, chestnut beetles, etc. Stomach poison should be used for treatment; For sucking mouthparts pests such as chestnut aphid and chestnut gall midge, internal sucking conductive chemicals should be selected; Contact insecticides and fumigation insecticides have good control effects on adult chestnut gall midge and fruit-eating pests such as chestnut gall midge and peach fruit borer larvae.
According to the hydrophobic and lipophilic characteristics of wax secreted by some pests and scale insects, chemicals with strong adhesion, such as oil emulsion, pine alkali mixture or chemicals with washing powder and synergist, are selected for control, and the effect is remarkable. High temperature and low humidity have good effect on pest control, but low temperature and high humidity have poor effect. For chestnut aphid, chestnut aphid, chestnut red spider, chestnut blight, chestnut anthracnose and other diseases, in sunny days, when the temperature is high and low, pesticides can effectively penetrate into pests and be easily absorbed by trees, thus effectively achieving the purpose of prevention and control. From June to September, the temperature is particularly high, which is the fruit expansion period of chestnut. At this time, attention should be paid to the selection of concentration and medicament to avoid phytotoxicity and fruit drop. Pay attention to the weather changes in rainy season. If it rains heavily after application, it will not only waste money, but also fail to achieve the control effect.
If pests and diseases have broken out, they must be prevented and controlled in rainy days. Synergistic adhesive should be added to the medicine to improve the ability of resisting rain erosion, so that the efficacy of the medicine can be maintained even if it rains heavily half an hour after application. If the rain stops soon, or it rains in Mao Mao, the concentration of chemicals should be higher to reduce the dilution of chemicals by rain. If there is wind when applying pesticide, it is best to stop applying pesticide, so as to avoid the pesticide being blown away by the wind, the leaves can not be adhered by the pesticide, and it is easy to cause poisoning to the pesticide users. Like light, insufficient light can cause branches to die or bear no fruit. Not strict with the soil, like fertile, moist, well-drained sandy or callose loam, and have strong resistance to harmful gases. Avoid stagnant water and sticky soil. Deep roots, developed roots, strong germination, pruning resistance and many pests. In addition, its varieties are cold-resistant and drought-tolerant. Life span is as long as 300 years.
Castanea mollissima has a wide crown and large branches and leaves, so it is suitable for planting alone or in groups on lawns and slopes in parks. It can also be used as tree species for afforestation and soil and water conservation in mountainous areas. Mainly engaged in the production and cultivation of dried fruits. Chestnut has been cultivated in China for more than 2000 years, and there are many varieties in various places. Therefore, attention should be paid to the selection of local fine varieties in breeding. Chestnut has strong adaptability, convenient cultivation and management, stable yield and is deeply loved by the masses. People in North China call chestnut a "hardcore crop", which is a good tree species combining greening and production. Seedlings begin to blossom and bear fruit in about 6 years, which is late in flowering and low in yield. In production, 2-3-year-old seedlings are often used as rootstocks and grafted before and after leaf opening. Don't plant too deep, it is better to expose the root neck of the seedlings. Treat pests in time.
I. Selection of Chestnut Orchard
Chestnut orchard should choose sandy loam with low groundwater level and good drainage. Avoid planting in places with saline-alkali soil, low humidity and strong wind. In order to open up millet orchards in hilly areas, we should choose areas near mountains with gentle terrain and thick soil layers, and then gradually expand to areas with poor conditions.
Second, variety selection
The selection of varieties should be based on local excellent varieties, such as Paoche No.2, Chen Guo 1, etc., and Shi Feng, Jinfeng, Haifeng, Qingmaoruanci, Chushuhong and other varieties should be introduced appropriately. According to different edible requirements, fried chestnut varieties should be given priority to, and excellent chestnut varieties should be developed appropriately, taking into account foreign trade export and domestic market demand. At the same time, early, middle and late varieties should be reasonably matched.
Third, rational allocation of pollination trees.
Chestnut mainly spreads pollen by wind. However, due to cross-pollination and self-pollination of chestnut, a single variety often produces empty bracts due to poor pollination. Therefore, new chestnut orchards must be equipped with 10% pollination trees. Practice has proved that it is better to use Chushuhong as pollination tree in Xinyang City.
Fourth, reasonable close planting.
Reasonable close planting is the basic measure to improve the yield per unit area. It is advisable to use 30-40 plants per mu in plain chestnut orchards and 40-60 plants per mu in mountain chestnut orchards. It is planned to plant 60-11plant per mu in close planting chestnut orchard, and then gradually carry out alternate thinning.
Verb (abbreviation for verb) Fertilize reasonably.
Rational fertilization is an important basis for high yield of chestnut orchard. The base fertilizer should be mainly soil mixed fertilizer, so as to improve the soil, improve the soil's ability to retain fertilizer and water, and provide more comprehensive nutrient elements. The best application time is autumn after fruit picking, during which the temperature is high and the fertilizer is easy to decompose; At the same time, it is in the new root stage, which is beneficial to absorption, thus promoting the accumulation of nutrients in the tree and playing a good role in the differentiation of female flowers in the coming year. Topdressing is mainly available nitrogen fertilizer, combined with phosphorus and potassium fertilizer, and the topdressing time is early spring and summer. Generally, topdressing is 0.3-0.5 kg urea per plant of newly planted fruit trees in spring, and 2 kg urea per plant in full fruit stage. After topdressing, water should be combined to give full play to fertilizer efficiency. Topdressing in summer is carried out from late July to mid-August. At this time, the application of available nitrogen fertilizer and phosphorus fertilizer can promote the increase of fruit grain number, full pulp and improve fruit quality. Top dressing outside the roots can be carried out many times a year, and the key points should be done twice. Spraying 0.3%-0.5% urea and 0.3%-0.5% borax for the first time in early spring when the basal leaves of branches turn from yellow to green, promotes the function of basal leaves, improves photosynthesis and promotes the formation of potted flowers. The second time, spraying 0. 1% potassium dihydrogen phosphate twice at intervals of1month and half a month before harvest, the main function is to improve photosynthetic efficiency, promote the transfer of nutrients such as leaves to fruits, and obviously increase the weight of single grain.
Irrigation with intransitive verbs
Chestnuts like water. Generally, watering once before germination and once during the rapid growth period of fruit is beneficial to the normal growth and development of fruit trees and the improvement of fruit quality.
Seven, plastic pruning
Pruning of chestnut trees can be divided into winter pruning and summer pruning. Winter pruning from defoliation to germination in the following spring can promote the growth of millet trees and the formation of female flowers. The main methods are cutting short, thinning branches, retracting, slow releasing, pulling branches and carving. Summer pruning mainly refers to germination, pit removal, emasculation and branch thinning in the growing season, and its function is to promote branching, increase female flowers, and improve seed setting rate and single grain weight. 1, shortcut: cut off part of annual branches. Short cutting can promote branching, enhance tree vigor, compact crown, reduce male flowers and adjust nutrient distribution. The leafy trees can be pruned in a delayed way, and they can be cut short after germination. 2. Retraction: it is a short cut of perennial branches. It is mostly used for perennial branches with weak growth, outward displacement of fruit and serious exposure in holes. 3. Drainage: that is, the raw branches, light blocking branches and slender branches in the cavity are drained from the base. 4, wearing a hat scissors: cut short near the new sharp wheel mark in winter, and the coring time is different. Leave 2-4 small buds on the ring mark of the new tip, which is called movable cap pruning. If handled properly, only the small buds on the cap and the big buds under the ring mark can produce fruiting branches. Leaving no short buds on the ring mark of the new tip is called wearing a dead hat to prune, so that the big buds under the ring mark produce fruiting branches. Under normal circumstances, the weak branches wear dead hat scissors, and the strong branches wear live hat scissors. 5, slow release: slow release is not cut. Its main function is to disperse nutrition and relieve tree vigor. Slow-release pruning is often used for lush trees. 6. Branching and scribing: For the strong and vigorous auxiliary branches whose crown is not pitted, flatten them when the juice flows to the bud in spring, and scribble above the bud that needs to germinate, so as to make them grow strong and vigorous branches. When pruning in winter, the slowly released and leveled branches are retracted to the part where the strong branches are drawn. 7. Nucleation: When the new bud grows to 30 cm, remove the top of the new bud. Mainly used for flourishing branches, the purpose is to promote early fruiting of branches. Pick your heart 2-3 times a year. The new buds of the first fruit-bearing trees are long and lush. When the front branches of the fruit grow out, 3-5 buds are left for picking. After the top of the fruit is pitted, about three thick branches can be formed, which increases the proportion of fruiting branches and slows down the outward migration of fruiting parts. 8. castration: only a few male inflorescences are left on the branches, and the rest are gone. Its main function is to control nutrition, promote the formation of female flowers and improve the strength of fruiting.
Eight, thinning flowers and fruits and pollination
When thinning flowers, you can directly remove young flowers and inferior flowers by hand, and try to keep big flowers and good flowers. Generally, it is advisable to leave 1-3 female flowers per fruiting branch. It is best to use fruit thinning scissors and leave 1 single bract on each node. When thinning flowers and fruits, we should master the principle of leaving more outside the crown and less inside. Artificial pollination should choose varieties with good quality, large grain, early heating period and easy peeling as pollination trees. When the anthers of the male inflorescence on a branch or most flower clusters in the male inflorescence just change from green to yellow, spread the collected male inflorescence on glass or clean white paper before 5 am, put it in a dry and windless place, turn it twice a day, and put the fallen pollen and anthers into a clean brown bottle for later use. When the polymorphic stigma of three female flowers in an involucre completely extends to the inverted yellow stone, dip the pollen on the inverted stigma with a brush or pencil with a rubber head. If the height of the tree is not convenient for dipping, it can be made by shaking gauze bags or spraying powder according to the ratio of pollen 1 serving and sweet potato powder filler of 5 parts.
IX. Harvest and storage
1. Harvest: There are two ways to harvest chestnuts, namely picking chestnuts and beating chestnuts. The method of picking chestnuts is to pick chestnuts manually after the chestnuts are fully heated and naturally fall to the ground. In order to pick chestnuts easily, weeds on the ground should be removed before chestnut buds break out. When harvesting, shake the tree first, and then pick up all the fallen chestnuts. Be sure to pick it up every morning and evening. The advantages of chestnut picking method are full chestnut, high yield, good quality and strong storage resistance. The chestnut beating method is to knock down the mature chestnut bracts in batches with bamboo poles, and then pick up the chestnut bracts and chestnuts. Harvesting in this way is usually carried out every 2-3 days.
When the buds are opened, tap the twigs inward from the periphery of the crown to shake off the chestnut buds so as not to damage the branches and leaves. It is forbidden to lay all chestnut buds with different maturity at one time. The harvested chestnuts should be treated as soon as possible, because the temperature is high, the water content of chestnuts is high, the breathing intensity is high, and a lot of heat is generated. Chestnuts are easily moldy if they are not treated in time. The treatment method is to choose a cool and ventilated place, spread a thin layer of chestnut bracts with a thickness of 20-30 cm, water them every day, cool down and sweat for 2-3 days, and then thresh them manually.
2. Storage: Chestnut has three fears: one is afraid of heat, the other is afraid of dryness, and the third is afraid of freezing. Storage mainly includes the following methods:
① Sand storage method: outdoor trench (pit) storage. Choose a well-drained site and dig a ditch with a width of 1m, a depth of 60cm and an unlimited length. After leveling, lay a layer of wet sand (water content 30-35%) on the bottom of the ditch, put a layer of chestnuts, and layer by layer in turn. Each layer of sand chestnut is about 5-6 cm thick. Top sand distance from pit surface 10 cm. You can insert straw into the pit for ventilation, and finally seal the soil into a ridge to prevent rainwater from infiltrating.
② Storage with bracts: Choose a well-drained site, lay sand with a thickness of 10 cm on the ground, and pile bracts in the open air. The size of the pile can be changed, but the maximum is not more than 1 m, and it is easy to heat up if it is too high. Cover the pile with stalks. Pay attention to check. If the pile is hot or dry, it can be properly splashed with water to cool and moisturize. This storage method is simple and labor-saving, and the storage period is long, and it can be stored until March-April of the following year, but chestnuts stored with bracts are easy to germinate. If the bracts are damaged by weevils, it is not easy to use this method, because the storage humidity is high, which is conducive to weevil activities.
③ Plastic film tent or film bag storage: Normal and mature chestnut fruits can be stored in film tent or perforated film bag after sweating and heat dissipation 1 month. Film bags can be placed in bamboo cages, wastebaskets or wooden cases. In order to prevent mildew, the fruit should be washed before bagging, soaked in 500 times of Tobezin solution for a few minutes, dried and bagged. The suitable capacity of the film bag is 25 kg, the film thickness is 0.05 mm, and holes with a diameter of 2 cm are punched on both sides of the bag, and the hole spacing is 5 cm. If non-porous bags are used, they should be inspected at any time to facilitate ventilation and moisture dissipation. When the temperature is high and the humidity in the bag is too high, the Qin Ying should be checked to reduce rot, germination and weightlessness. When chestnut blossoms, bears fruit and shoots grow, it consumes a lot of nutrients. At this time, if sufficient nutrients are not supplied, especially the required boron fertilizer is lacking, the normal growth of chestnut trees will be affected, resulting in an increase in the number of empty buds, low yield and poor quality of chestnut in that year. Two fertilization methods of chestnut were introduced:
1. Soil fertilization method
This method is effective in chestnut orchard with thin soil and serious lack of fertilizer. The method is as follows: digging 1 circular groove at the crown drip line of chestnut tree, with the groove width of 25cm and the groove depth of 20cm, and applying 1 kg of calcium superphosphate, 0.3kg of urea and 0.25-0.5kg of borax per plant. When applying, urea and borax should be dissolved in water before applying to the border, and water should be splashed when applying fertilizer. The fertilizer and soil should be mixed evenly with a hoe to make the fertilizer water penetrate into the root system as soon as possible and be absorbed and utilized by the root system. After applying fertilizer, it should be returned to the border in time to prevent nutrient volatilization. If a proper amount of soil miscellaneous fertilizer is added to fertilize the soil, it will have a good effect on chestnut bearing more fruits in the coming year and reducing the rate of empty bracts.
2. In vitro fertilization
This fertilization method is suitable for chestnut trees in various soils in summer. The method is as follows: 0.3%-0.4% urea solution, 0.3%-0.5% potassium dihydrogen phosphate solution and 0.3%-0.4% borax solution are mixed, and the tree crown is sprayed at 9: 00 am or at night on sunny days, once every 10 day and twice continuously. After spraying fertilizer, in case of heavy rain within 10 hour, it must be sprayed again to ensure the fertilization effect.
In summer, if soil fertilization method is combined with external fertilization method, the yield increase effect of chestnut will be better.
3. Boron application reduced the rate of empty bracts.
The problem of chestnut "empty bud" has a great influence on chestnut yield. In addition to artificial pollination, there is an effective method for chestnut flowering, that is, applying boron fertilizer.
① Types of boron fertilizer and boron application methods
The commonly used boron fertilizer is borax, which contains boron 10.8% and is soluble in warm water. Boric acid, containing 16.8% boron, white crystal, soluble in water. Boron application in soil adopts annular ditch or radial ditch with a depth of 20 ~ 80cm. When it is rainy or combined with boron irrigation, it is not necessary to dig a fertilization ditch, and shallow fertilization can be used in blocks. Because the validity period of boron application in soil is as long as 2 ~ 3 years, the effect in that year was not very significant. Therefore, it is necessary to combine foliar spraying. The concentration of borax sprayed on the leaves is 0. 1%-0.3%, and that of boric acid is 0. 1%-0.5%.
(2) Period, climate and application amount of boron. In mid-April, about 0. 1 kg should be applied to each mature tree soil, and the application amount per mu should not exceed 12 kg, otherwise it will cause chestnut poisoning. Deep application in sunny days, shallow application in rainy days. Foliar spraying should be done once in the early flowering period and once in the full flowering period in June. It is best to spray it on cloudy days in hot weather, and it should be sprayed on the back of leaves before 10 in the morning or after 4 pm in sunny days, but it is not suitable for spraying in rainy days. If 0.3% urea and 0.3%~0.5% calcium superphosphate are used together, the effect will be better.