Why do apple trees get root rot? An analysis of the latest causes
Everyone must eat apples often, and the apple-growing areas in our country are relatively large, with a great many apple varieties. But as the apple-growing areas get larger and larger, more and more problems appear, and root rot and yellow leaves are one of them. Fruit tree root rot reduces the tree vigor of the fruit trees, and can even kill the trees, and many pathogens will remain in the orchard, which is extremely unfavorable to the growth of new trees later on. So what causes root rot and yellow leaves in apple trees? Let's take a look below.
1. Uneven fertilization
Some fruit growers use nutrient ratios in fertilizers that are completely unsuitable for apple growth, for example, long-term use of chemical fertilizers such as urea and potassium sulfate. This causes the soil to become dry and hard, reduces soil permeability, affects the respiration of the tree roots, weakens the ability to absorb nutrients, and leads to various problems. Moreover, in order to increase yield and promote early ripening, large amounts of nitrogen fertilizer are applied, causing the apple trees to grow excessively, to flower without setting fruit, and worsening the root rot of the apple trees. Attention should be paid to the combination of elements, and fertilization should not be single; this is especially true of trace elements, because a lack of trace elements makes fruit trees prone to physiological diseases.
2. Improper use of farmyard manure
What fruit growers like to use most is farmyard manure. Farmyard manure has a low cost and good effects, but many people do not have the correct method of applying it. Farmyard manure must be fully decomposed before it can be applied to the orchard. Undecomposed farmyard manure produces a large amount of heat, and the tree roots cannot withstand the high temperature, which causes root burn and the phenomenon of root rot. In addition, the heat produced during the decomposition of farmyard manure kills the pathogens lurking within it, so if it is not decomposed, it will cause a large number of pathogens and other harmful substances to breed in the soil. This has a relatively serious impact on the growth and development of the roots.
3. Fertilization time
Many fruit growers fertilize whenever they feel like it, applying it whenever they want. In fact, this seriously hinders the growth of the fruit trees: the tree roots lack nutrients and cannot provide enough nutrients to supply growth. In fact, in the planting process there are requirements for the timing of topdressing, especially during the period after harvest. Harvest is generally in autumn, and after harvest the base fertilizer should be applied in sufficient quantity, because all the nutrients of the fruit tree have been concentrated in the fruit, and at this time the fruit tree is in an extremely weak state. If nutrients are not replenished for the fruit trees in time, the fruit trees are prone to freezing damage when overwintering.
4. Unsuitable soil
When planting, fruit growers usually neglect the management of the orchard soil, do not carry out intertillage work on the soil, and also use chemicals for weeding. They do not loosen the soil or strengthen the permeability of the soil, and the soil remains in a closed, dry and hard state for a long time. This forces the roots of the fruit trees to gradually extend toward the upper part of the soil, so that even a slight lack of water or excess water will damage the roots. The tree roots cannot breathe, the fruit trees lack nutrient supply, and the tree vigor gradually weakens, with a large amount of leaf drop and root rot.
The above four points are the main causes of root rot in apple trees. Root rot in apple trees not only affects the respiration of the tree roots and nutrient absorption, but also threatens the growth of the fruit trees and the final yield and quality. As can be seen above, the main causes are almost all brought about by various aspects of fertilization, so everyone should master the correct fertilization techniques and minimize the adverse situations as much as possible. This article is for reference only, and we hope it is helpful to everyone.