What are the characteristics of the rooting system of fruit trees?

Rooting system: The original root system produced by seed propagation is called rooting system. A single fruit tree directly produced by seed propagation is called a seedling from the root system. Because the seeds are mostly produced by cross pollination and hybridization, and the genotypes between grains are different, the fruit trees that are directly propagated have great differences in fruit and other characters, and the fruit-bearing years are generally longer. Therefore, the production does not meet the needs of modern commercial fruit production, so this method is not suitable.

In a typical root system structure, the taproot grows rapidly and develops downwards, while the growth of the horizontal root system is inhibited. Developed taproots can effectively absorb water and nutrients in deep soil, with good soil consolidation and strong wind and lodging resistance. However, because most of the activated nutrients in the soil are in the 0 ~ 60 cm soil layer, they are absorbed by the horizontal root system and supplied to all parts of the ground, so this primitive root system must be transformed and utilized. In production, the seeds of some wild materials are used as rootstocks and the fruit trees formed by grafting fruit tree varieties have certain production significance.

Wild resources have strong adaptability to the environment and outstanding resistance. Some excellent characters of natural domestication have created favorable conditions for the development of fruit trees in places with poor site conditions. For example, if apple varieties are weak in salt and alkali resistance, using Xifu Begonia with strong salt and alkali resistance and drought resistance as rootstock can increase the absorption intensity of iron, zinc, boron and other elements in the soil and reduce the cork degree of yellow leaves, leaflets and fruit epidermis of apple trees. In the utilization of seedling roots, we should pay attention to cutting off the main roots by 20 ~ 30 cm in the first or second year of seedling raising, so as to increase the number and development degree of horizontal roots and lay the foundation for better absorbing soil nutrients and realizing early fruit in the future.