How to cultivate red Fuji apple

I. Cultivation of moderate tree vigor The content of chlorophyll, soluble solids, and fruit coloration index of the golden mean tree were higher than those of the imaginary tree and the weak tree. When the ratio of the thickness of the stem branches to the result branches was 25%, the fruits were large and colored well; when the ratio of the thickness of the two branches was greater than 30%, the heads of the fruits were large, but the color was poor. Both the backbone branches and the result branches are weak, not only small but also abnormally colored. Therefore, the maintenance of a moderate tree and strong tree vigor is crucial for the production of Red Fuji Red Fruit.
2. Ensure sufficient light in the tree crown Red Fuji apples are sensitive to the light. The fruit on each branch gets full red when it is more than 70% of full sunshine, and when it gets 40% to 70% of full sunshine, the fruit surface is red, and when the whole day shines below 30%, the fruit surface is not colored. In order to ensure that the tree has sufficient light conditions, in the trimming technique, it is necessary to change the winter cut to the heavy summer cut. When winter cuts, the slow-release flattening of the prosperous branches, more sparse not cut, the amount of mu branches maintained between 80,000 to 100,000. In the tree shape, the natural semicircle is changed into the five main double-layered happy shape, and the apple orchards are planted with more than 83 orchards, and the spindle shape should be adopted. No matter which kind of tree shape, it is necessary to achieve few main branches, low grades, large angles, and the following hanging-type branch groups are the main ones, so as to ensure that the canopies are airy and light-transmitting, and the fruits are brightly colored.
Third, the regulation of leaf mineral nutrient ratio Red Fuji apple tree leaf nitrogen content greater than 2.5%, the petiole was green, the fruit difficult to color; nitrogen content of less than 1.5%, petioles, veins are purple, pale fruit color; When the leaf nitrogen content was about 2%, the petiole was purple-red, the leaves were dark green, and the fruit was well-colored. From August onwards, it is not advisable to chase nitrogen fertilizer before fruit harvest. At this time, topdressing potassium fertilizer can promote coloration. The higher the soil potassium content, the better the fruit coloring.
Fourth, other technical measures
(1) Moderate irrigation. During the early stages of fruit development, a certain amount of fertilizer is maintained, and in the middle period, a certain amount of soil moisture must be maintained. In the later period, water must be controlled. Heavy rain or flood irrigation in the late period is not conducive to improving the sugar content and coloring of fruits. If the late climate is indeed dry, sprinkler irrigation can be used; (2) Tree trays cover grass during the early summer and late fall, which can protect the roots of fruit trees, enhance the absorption capacity of surface roots, and have obvious effects of increasing sugar and color, and improving fruit flavor; (3 ) Picking leaves, turning fruit, and hanging branches. Twenty days before fruit harvesting, the leaves that were shaded and attached to the fruit surface around the fruit were removed, and the coloring area was increased by about 15%. 4 to 5 days after picking the leaves, gently hold the fruit by hand to turn the dark side to the sun's surface so that it will see the light in the abdomen and back, which can increase the coloring index by about 20%; (4) Spray the rare earth elements on the leaves and apply 500 when the fruit is near to coloring. The mg/kg rare earth solution can make the coloring of Fuji color 12 to 17 days earlier.