Fertilization techniques for increasing sweetness of citrus with declining quality and flavor

In recent years, citrus growers have extensive management, partial application of chemical fertilizer in fertilization, and do not pay attention to the application of organic fertilizer, which leads to the decline of citrus fruit quality and the deterioration of citrus flavor. In production management, the following technical measures for sweetening and fertilization should be taken:

Citrus fertilization

First, no partial application of nitrogen fertilizer. The application of a large amount of chemical nitrogen fertilizer can promote the vegetative growth, delay the coloring, lighten the color and thicken the pericarp, which is not conducive to the improvement of citrus sweetness. Potassium fertilizer can promote the growth of citrus, but if the leaf surface contains too much potassium, it will increase the acidity of citrus and weaken the flavor of citrus.

Second, increase the application of organic fertilizer. The application of organic fertilizer in citrus production, especially all kinds of cake fertilizer and multi-component organic-inorganic compound fertilizer, can not only meet the needs of nitrogen, phosphorus and potassium, but also supplement trace elements such as magnesium and zinc, improve soil fertility and increase the sweetness of citrus.

Third, apply base fertilizer early. Fruit growers are traditionally used to applying base fertilizer from winter to early spring, which is not conducive to the absorption and storage of tree nutrients, thus affecting flower bud differentiation, so base fertilizer should be applied in time after fruit harvest.

Fourth, increase the application of calcium fertilizer. The main results are as follows: 1. The soil contains low calcium and high acidity of citrus, so the soil of citrus orchard applies calcium fertilizer such as lime, superphosphate and so on. Lime is generally applied 60kg per mu, once every 3-4 years. 2. Spraying foliar fertilizer. For a long time, foliar fertilizer containing high potassium or amino acid was sprayed to promote the ripening of new leaves and store nutrients. 3. Foliar spraying 0.2% calcium dihydrogen phosphate plus 0.2% sodium dihydrogen phosphate is beneficial to increase the sugar content of citrus; in the mature period of high temperature, appropriate spraying of 100-200ppm 's "sweet treasure" solution; in the later stage of fruit growth, spraying 2% lime water and 0.4% salt is beneficial to improve tree photosynthesis, prevent high temperature fruit burning, promote coloring, improve citrus flavor quality, and mature 710 days earlier. 4. Apply sweetener, 700kg water + 200g pure boron + 2.4% sucrose; 0.7g calcium chloride + 99.57% ammonia thiosulfate + 0.43% sodium dodecyl sulfate + 2000 times clean water. When the citrus begins to color, spray the tree bag ground, spraying 0.5 liter per square meter, and spray again every 10 days.