(1) Select suitable planting areas and select fine varieties. (2) Moderately close planting, the application of dwarfing rootstocks has high density and insufficient light, which affects fruit coloring. (3) Scientific fertilization and watering Scientific fertilization is the premise of high quality and high yield of apples. Increase soil organic matter, plant grass in orchard and apply more organic fertilizer to make the organic matter content reach 2% ~ 3%. Balanced fertilization, too much or too little of some elements will affect the quality of fruit. Too much nitrogen will affect fruit coloring and sugar accumulation; Insufficient nitrogen will affect the growth of fruits. Potassium can enhance the disease resistance of fruit and promote fruit coloring. When the N/K value is 1.2, the apple is best colored. Proper fertilization, nitrogen fertilizer is mainly topdressing before germination or flowering, and phosphorus and potassium fertilizer is mainly topdressing after fruit expansion period, which can obviously increase the weight and coloring of single fruit. Topdressing nitrogen fertilizer before harvest can increase the fruit size, but it seriously affects the coloring. Spraying fertilizer on leaves, starting from the end of June, spraying liquid potassium dihydrogen phosphate every 15 days, which is beneficial to coloring. In addition, spraying photosynthetic micro-fertilizer, rare earth micro-fertilizer and amino acid micro-fertilizer is beneficial to coloring.

It is necessary to control the moisture in the orchard reasonably. Soak in water before germination. During germination, drought will cause late germination, short buds and small leaves, which will affect the fruit expansion in the later stage. Drought or rainy flowering period, poor pollination and fertilization, easy to produce deformed fruit, crooked fruit. The young fruit period after flowering should not be dry, otherwise it will easily cause fruit drop and affect fruit growth. Adequate water supply during fruit expansion period is beneficial to fruit growth. During this period, the fruit is small and flat. After entering the coloring period, it is necessary to properly control moisture and pay attention to drainage. In the later period of heavy rain, the fruit showed color difference, low sugar content and serious fruit rot. Irrigation after a long drought in the later period is easy to cause fruit cracking, especially in sandy orchards. Moderate drought before harvest is beneficial to coloring, but excessive drought and low air humidity make fruits difficult to color. (4) Reasonable shaping and pruning illumination has great influence on the growth and development of fruits, especially the coloring of fruits and the content of internal sugar. Insufficient light, poor flower bud differentiation, small fruit, large color difference and low sugar content; If the light is too strong, the fruit is easy to get sunburned. Through reasonable shaping and pruning, the orchard and crown are ventilated and transparent. When pruning, choose the appropriate tree shape, control the height of the tree, remove dense auxiliary branches, and open the branch angle, so that the tree potential is moderate and robust, the leaf area coefficient is between 3 and 5, the number of branches per 667 meters is 80,000 ~ 654.38+million, and the crown light transmittance is above 30%.

The growth potential of trees is closely related to the size and color of fruits, and the annual growth of peripheral branches represents the growth potential of trees. The annual growth of new shoots of Fuji varieties should be kept at about 40 cm, and the tree potential is moderate. The weight of single fruit can reach more than 200 grams, and the coloring index can reach 80%.

The strength of fruiting branches and fruiting mother branches also affects the quality of fruits. Generally, when the mother branch bears fruit for three to four years, the fruit is larger. Through the alternate regeneration of branches and fruit branches, most of the mother branches are in the stage of three to four years, leaving solid fruit branches. Even if the apple is cut and opened for a long time when it is young, the branches will become thinner and longer, the buds will become thinner, and the fruit will become smaller and discolored. At this time, it is necessary to carefully prune, remove the weak and stay strong, remove the drooping and stay oblique, remove the old and stay new, and remove the far and stay close, so that the fruiting branches and fruiting branches can be rejuvenated.

There is a significant difference between the auxiliary tip of fruit platform and the fruit weight of the same period. When the auxiliary tip of Fuji variety is 20 cm, the single fruit weight of the same stage is the largest. In the first ten days of June, the top secondary shoots of long single fruit were reserved for 20 cm coring, and one secondary shoot was selected for 20 cm coring, and the other was drained from the base, so the weight of single fruit could be increased by18.7 ~ 29.6438+0 g. After entering the fruit coloring stage, reasonable pruning or retraction of branches that are too vigorous, crowded, clustered and fruitless can significantly increase the crown light transmittance and improve the fruit coloring degree. (5) Improve the quality of pollination and fertilization, improve pollination and fertilization conditions, increase the fruit setting rate, ensure the number of seeds in the core, and reduce crooked fruits, flat fruits, small fruits and abnormal fruits through artificial pollination or release of wallbees. The more seeds in the fruit, the bigger the fruit and the higher the fruit pile. There are few seeds in the fruit, and the fruit is small and flat, which is easy to cause uneven distribution and produce crooked fruit and deformed fruit. According to the investigation, compared with natural pollination orchard, the fruit setting rate of inflorescence in orchard pollinated by wallbee increased by about 20%, the average number of seeds of fruit increased by 3.4, the weight of single fruit increased by 35 grams, and the partial fruit decreased by 70%. (6) Reasonable loading, precise fruit preservation and strict control of fruit preservation. Generally, the branch-fruit ratio of small fruit varieties is 4 ~ 5: 1, and 1 ~ 2 fruits are left on each fruit table; The proportion of big fruits such as Red Star and Fuji is 7-8: 1, and only 1 fruit is left on each fruit table. Keep the central fruit, the fruit on the strong branches, the lateral fruit, the drooping fruit, the straight fruit, the big fruit and the fruit without pests and diseases. (7) Take measures to promote fruit coloring, such as bagging, spreading reflective film, picking leaves, turning fruit, etc.

Fruit bagging is an important measure to promote fruit coloring and improve fruit surface smoothness. (2) Laying reflective film.

After the fruit is bagged, silver reflective films are laid inward along the outer edge of the crown, one on each side of each row of trees. Experiments show that the light intensity under the crown can be increased by 4 times, the calyx depression can be completely colored, the chlorophyll content in the crown cavity leaves can be increased by more than 60%, and the anthocyanin content in the peel can be increased by more than 2 times. 3 Pick leaves.

Picking leaves can prevent spots on the surface of fruits. Leaves should be picked after bagging. Shaded leaves and sticky leaves within 5 ~ 15 cm around the fruit should be removed, so that more than 60% of the fruit surface is irradiated by direct light. Leaves should not be picked too early, but in stages to prevent sunburn, discoloration of fruit surface and adverse effects on flower buds and tree storage nutrition. The total number of leaves picked should not exceed 30% of the total number of leaves. 4 turn over the fruit.

When the sunny side of the fruit is colored, it is necessary to rotate the fruit manually in order to brighten the negative side of the fruit. Make the original shade sunny and promote the full coloring of the fruit. The fruit close to the branch can be rotated by hand 180 degrees and then stuck to the branch; In the case of double fruit, turn in the same direction 180 degrees and lean together; For drooping fruits, they can be pulled and rotated by transparent plastic tape 180 degrees and fixed on nearby branches. After fruit transformation, the coloring index can be increased by about 20%.

(8) Strengthen plant protection to ensure that Yequan is free of pests and diseases. In autumn, leaves are intact and do not fall early, which can ensure the nutritional supply of fruit development and is beneficial to fruit coloring. Pay attention to the prevention and control of fruit diseases and insect pests, such as mildew and ring rot, as well as fruit eaters, leaf rollers, corn weevils, mealybugs and so on. Supplementing boron fertilizer during the growth period to reduce the occurrence of fruit shrinkage disease; Supplement calcium fertilizer to prevent physiological diseases such as bitter pox and water heart disease.

Before bagging, it is forbidden to spray Bordeaux mixture, organophosphorus and other chemicals that are irritating to the fruit and have residual spots to prevent the fruit from rusting. Don't spray bordeaux mixture after picking bags, so as not to affect the fruit coloring. (9) Rational application of plant growth regulator Red Fuji apple, spraying 6-BA at a dosage of 100 ~ 300mg/L 20 days after full bloom can increase the fruit size by 20 ~ 40g. Spraying Baiduoling or high-piling agent at full flowering stage and after flowering 1 week, using 500-fold solution for Red Fuji and 1000-fold solution for Starkrimson can obviously improve fruit shape index and fruit setting rate. Spraying 30 mg/L NAA about 20 days before harvest can prevent Marshal's fruit from falling before harvest. (10) should be harvested properly according to the variety characteristics and local climatic conditions. For example, the harvest of Marshal varieties should be carried out in the middle and late September, and the harvest of Fuji varieties should be carried out in the late June of 10, and fruit bagging should be postponed.