Guava belongs to the genus Psidium of Myrtaceae, which is scattered in tree shape, with long branches, round to oval fruit, large fruit, crisp pulp, not easy to soften, soluble solids between 8%- 14%, and excellent quality. At present, the price of pearl guava in autumn and winter fruit market in Zhuhai is around 4 yuan/kg, and the benefit is good. The main management points of the result tree are as follows:

Pruning, reshaping and dwarfing the crown.

In order to prevent the harm of fruit borers and improve fruit yield and quality, pearl guava should be thinned and bagged. In order to operate conveniently, it is necessary to control the annual crown height at about 2 meters. After harvesting the fruits in spring, cut off dead branches, pests and diseases, too dense branches and too drooping branches. Re-cut the thick branches to reduce the height of the crown. In summer, the terminal buds and adventitious buds should be properly erased to prevent the branches from being too dense and too long, and to keep the branches evenly distributed in the crown. After the bud of the new bud blooms, the main branch is pulled horizontally, the tree body is dwarfed and the crown is open.

Timely fertilization promotes high yield

Pearl guava can blossom and bear fruit all year round, with a large amount of flowers and fruits. It needs enough fertilizer and water. What is the weight of fertilization? Guava with red heart

The emphasis is on the sprouting of branches and the fruit expansion period. Fertilization is generally applied once in February to promote bud germination, and urea is mainly used in conjunction with phosphorus and potassium fertilizers. Fertilize in May and June to strengthen the fruit and promote the secondary branch germination, mainly using compound fertilizer. In July and August, the second flower-making and flower-promoting fertilizer was applied, mainly compound fertilizer. From September to June, 65438+ 10, the second fruit-making and fruit-strengthening fertilizer was applied, mainly phosphorus and potassium fertilizer. Basic fertilizer, mainly organic fertilizer, was applied in February. Fertilize more than 5 times a year. In addition, combined with pest control, foliar topdressing is carried out to supplement trace elements such as zinc, boron and molybdenum.

Thinning flowers and fruits, bagging in time.

Pearl guava has many flowers and many fruits. In order to improve the quality of fruits, it is necessary to thin flowers and fruits during the flowering and fruiting period, remove heavy flowers, three flowers and stunted flowers in time, keep strong single flowers, and properly thin fruits, generally leaving 1-3 fruits per branch. When the fruit grows to a diameter of about 3 cm, it is sprayed with pesticides and fungicides once and bagged. The inner layer of the fruit protection bag is a white foam net bag and the outer layer is a transparent plastic film bag. Put the fruit in the bag, leave the leaves outside, tie the bag mouth tightly, and leave two small holes at the bottom of the bag, which is beneficial to ventilation and drainage. Bagging can reduce pests and diseases, reduce pesticide residues in fruits and improve fruit quality and appearance.

Adjust delivery time to improve efficiency

In Zhuhai, the fruits harvested from June to August in Pearl Guava are light in flavor and poor in quality. The price is lower, less than half that of autumn and winter fruits (10- March next year). In order to improve fruit quality and increase economic income, it is necessary to adjust the production cycle. The flowers of pearl guava mostly appear between the axils of 2-4 pairs of leaves of new branches, and buds appear when the new branches grow to 6-8 pairs of leaves after cutting. Therefore, we can adjust the production cycle by pruning, fertilizer and water regulation and other measures. The specific method is (taking autumn and winter fruits as an example): thinning flowers and fruits in time around May, and controlling the yield of this secondary fruit to adjust the tree potential. After fruiting, pick the core of the top 3-4 nodes of the fruit to make the top sprout new buds again, so as to prepare for flowering and fruiting again. Pruning is carried out around June, and dense branches, thin branches and aging branches are cut off, leaving well-developed and full-grown branches. At the same time, supplement fertilizer, water and control pests and diseases. To promote buds and flowers. After this treatment, a batch of flowers can usually bloom in Zhuhai from August to September, and fruits can be received after 10 months.

Edit the section of greenhouse cultivation

1. Variety selection. At present, the variety "Pearl" with large planting area and good yield and quality in greenhouse in the north grows rapidly, can blossom and bear fruit in the same year of planting, has high yield, easy cultivation management, strong disease resistance and good fruit flavor, and is deeply loved by the public.

2. Planting conditions. It is suitable for planting in sandy soil with deep soil layer, medium fertility and good drainage, and the height of most solar greenhouses in the north can meet the requirements of guava planting.

3. Cultivation techniques.

(1) The planting density before transplanting is 2m between plants and 3m between rows. Dig a planting pit with a depth of 60 cm and a diameter of 80- 100 cm, mix the dug soil with the decomposed organic fertilizer at a ratio of 9: 1, and then backfill it into the pit, and the backfill soil is 20 cm higher than the ground. (2) The suitable time for seedling transplanting is from mid-late April to mid-June. Before transplanting, the transplanted seedlings should be soaked in 800- 1000 times of thiophanate methyl 10 minute, and the seedlings with excessive water loss should be soaked in clear water for 6-8 hours before planting. When transplanting, put the seedlings into the planting holes, compact them with fillers, and bury the seedlings to a certain depth to keep the original soil seal. After planting, make a tree tray around it according to the size of the crown and shower it with root water.

(3) Water and fertilizer management: after pruning every year 1-2 years old, apply 3 kilograms of organic fertilizer, and apply NPK fertilizer after each pruning. The annual net NPK amount is100-150g/plant respectively; 3-4-year-old trees are applied with 5 kg of organic fertilizer, and the annual pure amount of nitrogen, phosphorus and potassium is 200-300 g/plant respectively; 7.5 kg of organic fertilizer for trees over 5 years old, and the annual pure amount of nitrogen, phosphorus and potassium is 400-500 g/plant. At the same time, we should pay attention to the application of trace elements such as iron and zinc. Irrigation should be based on keeping the soil moist, and it should be done every 10- 15 days in autumn and winter. (4) After shaping, pruning and planting, when the height of the seedlings is 50-60 cm, the seedlings are cut off to promote the development of new shoots, and 3-4 oblique branches with uniform distribution and appropriate branching angles are selected as the main branches. When the main branch is 30 ~ 40 cm long, pruning will promote branching, 2-3 branches will be selected as auxiliary branches, and then fruiting branches will be cultivated on the main branch and auxiliary branches. The pruning of young trees is generally based on light cutting, core picking and top pulling. After entering the full fruit stage, increase pruning efforts to promote the development of new shoots, and cut the big branches and main branches in time. With the increase and outward migration of fruit-bearing parts, the tree potential decreases, so it is necessary to prune and update the plants that have been bearing fruit for many years in time.

(5) The management of flower thinning in the flower and fruit period is generally carried out in the full flowering period from late May to late June, and a single inflorescence with new branches is reserved, with two flowers heading 1 floret, three flowers heading around, and the central sessile flower is reserved; The young fruit should be thinned in about 35 days, and the robust branches should be thinned by 2 per branch, and the branchlets should be thinned by 1 branch to remove abnormal fruits and diseases and pests. When the fruit grows to 2-3 cm in diameter, bag it, and spray 1-2 times of disease prevention chemicals before bagging.

(6) In greenhouse management, the optimum growth temperature of guava is 23-35℃, the low temperature tolerance of tree is 0℃, and the lowest temperature of fruit ripening is 65438 05℃. If the fruits are kept fresh in winter and spring, it needs to be heated to ensure that the minimum temperature is above 15℃, and the humidity in the shed can be reduced by the size of the tuyere.

(7) Pests and diseases control There are few guava diseases in greenhouses in the north, and the main pests are nematodes, which can be diluted with pesticides such as dichloroisopropyl ether, thiophanate or benzalkonium chloride before irrigation.

Edit the management points of this paragraph.

Guava can blossom and bear fruit many times a year. According to the amount of flowers, it can be divided into two types: forward flower making and reverse flower making. In Hainan, as far as the same orchard is concerned, there are fruits all year round, and most of them have turned over after August. When fruit hangs, it is often autumn and winter. At this time, the climate is changeable, hot and cold are impermanent, and there are typhoons, which is very unfavorable to guava production.

In this regard, the following methods can be adopted:

Appropriate growth inhibition, drugs to promote guava flowering after high temperature and high humidity in summer, and fruits are being harvested, most branches are lush and thick. It was observed that the flowering festival of guava increased obviously after entering August. Judging from the fruiting nodes of guava, 2.4.8 nodes are the most, and 8 nodes or 12 nodes have flowers. In addition, there are many branches, all of which are long branches, and the fruit setting rate is not high. After spraying B9 (Bijiu) 1 000-2000 ppm in late August, the flowering amount increased sharply. In addition, combined with coring, if the upper branches and leaves are picked at 5 or 9 nodes, they will often become flowers at 4 or 8 nodes. After taking measures, the amount of flowers is often 1-2 times of the allowable growth, and these flowers are very easy to bear fruit. However, when using drugs to promote flowers, the use of drugs will be different due to different seasons and climates. After entering 1 1, the weather turns cold, and the use of chlormequat can effectively prevent frostbite of florets. When using chlormequat chloride, borax should be used in combination. Chlormequat chloride can easily increase the bitterness of young fruits, but it can reduce the bitterness and increase the sweetness when mixed with borax.

2. Timely control of pests and diseases Guava pests and diseases are quite rampant in autumn and winter. Nematodes, mealybugs and rust are the main pests. Because of the lush leaves, mealybug pests are induced to thrive and hurt the buds. Shoots tend to turn black and shrink, and it is difficult to blossom. In addition, this pest has overlapping generations and needs continuous medication. Ruff and Kuailing have quick insecticidal effect. As for root-knot nematodes, it is particularly serious in autumn and winter drought, and it mostly occurs in sandy orchards, which often leads to the barren guava orchards. The diseased plants should be found as soon as possible, and the symptoms are as follows: the old leaves turn purple, gradually turn red, then wither, from bottom to top, the stems are bare and the branches are bare. If it is not controlled in time, the surrounding plants will have similar symptoms. Therefore, as soon as sporadic strains are found in autumn and winter, they must be used in time. Fine sand mixed with ground wormwood can be used for paving. When paving, the topsoil of the tree tray should be planed to make the soil mix evenly. This can generally control the spread. Rust mainly harms small fruits. Spraying mancozeb and bagging can greatly reduce the harm of small fruit peduncle facing down.

3. The practice of rational use of foliar fertilizer shows that it is effective to use foliar fertilizer in autumn and winter. 3% urea mixed with 1% calcium superphosphate can increase the yield. Mixing 0.2% borax and 0.5% potassium dihydrogen phosphate can promote fruit setting and increase sweetness. Due to the lack of light in autumn and winter, photosynthesis decreases, fruit is repeatedly hung, and guava flavor is easy to fade, so farm manure should be added and foliar fertilizer should be used at the same time.