There are four key water demand periods for apple trees in a year, namely, the budding period, the long-term growth of new shoots, the fruit expansion period and the deciduous dormancy period. Among them, the shoot growth and the fruit expansion period require the largest amount of water, which is called the critical period of water requirement. (1) In the bud stage: The better sensation, it is beneficial to sprouting shoots, and the soil moisture content should reach 70%-80% of the field water holding capacity. (2) Flowering period: The soil water requirement is sufficient, it is conducive to flowering and fruit setting, the flowering period is long, and the falling fruit is light. The soil moisture content should be 60%~70% of the field water holding capacity. (3) Critical period of flower bud differentiation: In order to control water in this period, new shoots can be stopped in time, flower bud differentiation is ideal, and soil water content should be 50% to 60% of field water capacity. (4) Fruit enlargement: In this period, there is sufficient water, and the fruit develops quickly. The soil moisture content should reach 80% of the field water capacity. (5) Mature period: Excessive water content in the coloring period will cause greediness and prosperous growth, which will be detrimental to coloring. Water in the mature period should be stable, water fluctuations are large, and fruit cracking can easily occur. The soil content should reach 80% of the field water capacity. (6) Dormant period: The soil moisture is sufficient to facilitate winter dormancy, and the soil moisture content should be more than 80% of the field water capacity. Disclaimer: Some articles in this website have been transferred from the Internet. If you are involved in third party legal rights, please inform this website. phone Vitamins are a type of trace organic substances that humans and animals must obtain from food in order to maintain normal physiological functions. In terms of physiological functions, vitamins are neither a raw material for tissues nor a substance for supplying energy, but they are an indispensable substance for the body. It has many types and different chemical structures. Most of them are the components of the coenzyme (or prosthetic group) of certain enzymes. They are the indispensable compounds for maintaining the normal growth (growth, health, reproduction and production function) of the body. It plays a catalytic role in the body to promote the synthesis and degradation of major nutrients (proteins, fats, carbohydrates, etc.), thereby controlling metabolism. Vitamins are essentially low-molecular organic compounds. They cannot be synthesized in the body, or the amount synthesized is difficult to meet the needs of the body, so they must be supplied from the outside. The daily requirement of vitamins is very small (usually measured in milligrams or micrograms). They are neither a raw material for body tissues nor a substance for energy supply in the body. However, they do not regulate material metabolism, promote growth and development, and maintain physiological functions. Vitamin K2 MK-7, Vitamin C, Vitamin E, Vitamin K2, Vitamin H, Vitamin D3 Xi'an Gawen Biotechnology Co., Ltd , https://www.ahualyn-bios.com