The reason for this is the following：
1. What are the disadvantages of bagging apples?
1. Bagging affects the content of fruit contents and the flavor is not ideal. Apple bagging overemphasizes the appearance quality of the fruit, which seriously hinders the entry of sunlight, thus making the bagged apple taste worse and the pulp hardness and sugar content lower.
2. The process of bagging and picking bags needs to increase labor cost and cost input of fruit farmers. According to the statistics of Yantai Agricultural Technology Center, there are 20-25 billion bags in the city every year, which is equivalent to the paper bag fee and the labor cost of bagging and picking, with a total amount of 4 billion yuan, accounting for 1/3 of the total production cost.
3. Bagged fruits are prone to calcium deficiency. Bagged fruit can't absorb calcium well, so the fruit hardness is reduced and the disease resistance is relatively weakened, which is easy to cause some specific diseases.
4. The skin of bagged fruit is easy to crack and the fruit surface is easy to burn. Apple bags are easy to block some leaves, affect the light path, increase the crown area with low light efficiency, and are prone to cracks.
5. Bagged fruits are not easy to be colored and easy to turn green and fade. Most fruits are unhealthy red, not natural red. Bagging affects the normal coloring process of fruits and the formation of anthocyanins to a certain extent, making the coloring worse than normal fruits.
6. Bagging fruit is easy to shrink in the later stage, and the apple becomes smaller; At the same time, it also affects apple production. After calculation, experts come to the conclusion that each set of fruit bags will cover at least 5 leaves on average, and 20,000 fruit bags per mu will cover a total of 654.38+10,000 leaves. Every 40 leaves can supply one apple, which will reduce the output of 2,500 apples per mu. A large number of leaves are blocked, so it is difficult to carry out normal photosynthesis, and the nutrient accumulation of fruit trees is reduced, which is bound to cause the tree to weaken.
Second, the specific introduction:
1, the function of apple bagging
Apple bagging [2]? Improving the appearance quality of goods is a supporting technology, and only by comprehensively strengthening the comprehensive management of orchards can the effects and benefits be reflected. Once the fruit is bagged, it can first make the peel delicate and bright, and the fruit points are thin and small, which significantly improves the appearance quality. Secondly, it can promote the rapid increase of anthocyanins in red varieties of fruits, expand the coloring area by about 30%, and make the colors uniform, bright and beautiful. Third, it can effectively reduce the residue and pollution caused by pesticides and dust to fruits. Fourth, it can prevent diseases, insects, birds, rats and bees from harming fruits and reduce fruit rust. Fifth, it can avoid the friction between branches and leaves, prevent sunburn and reduce mechanical injuries such as hail. Therefore, the wide application of fruit bagging is still the most direct and effective technology to produce pollution-free green fruits.
2. "Five choices" is the foundation.
Bagging fruit should choose excellent varieties with high added value Second, we should choose an orchard with clean appearance and high management level. Third, we should choose plants with light age, strong growth and good structure. Fourth, we should choose the fruits on the lateral branches and the middle and long branches, especially the central fruit, which is straight in shape, flat in shoulder, flat in top, closed in sepals, moderate in stalk and easy to droop. Fifth, we should choose high-quality fruit bags and apple fruit-cultivating paper bags that meet the local standards in Shaanxi. Such as Japanese Kobayashi, Taiwan Province Jiatian, Shandong Aimin, Hebei Shunda, Shaanxi Seiko, Sanqin, Linqin and other brands of paper bags, and resolutely ban plastic-coated fruit bags and inferior paper bags.
3. The standard paper bag should have:
(1) The outer bag is 180mm in length and 145mm in width, which is highly hydrophobic, wind-proof, sun-proof and rain-proof; Good shading and air permeability; The fruit has a high degree of chlorosis and rapid coloring; Soft paper, strong resistance to pests and diseases, strong tensile strength.
(2) The inner bag is 150 mm long and 140 mm wide, and the wax layer is uniform; Do not melt at high temperature; Good water resistance, separation of inner and outer bags.
(3) The process requires close adhesion and no cracking for a long time; One side of the outer bag mouth is clamped with a binding wire with a length of about 3-4 cm; One side of the bag mouth is a semi-crescent notch, and the center of the bag mouth is provided with a longitudinal cut of 2-2.5 cm; There is a longitudinal cut in the middle and two corners of the bottom of the outer bag and an air hole with a length of about 65438±0cm.