What causes root rot in apple trees?

Everyone must eat apples often. The area where apples are grown in our country is relatively large, and there are also very many apple varieties. However, as the area for growing apples grows larger and larger, more and more problems appear, and one of them is root rot and yellow leaves. Root rot in fruit trees reduces the tree vigor of the fruit trees, and can even kill the trees, and many pathogens 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 a nutrient ratio in fertilizers that is completely unsuitable for apple growth, for example, using chemical fertilizers such as urea and potassium sulfate for a long time. This causes the soil to become dry and hard, reduces soil permeability, affects the breathing 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, producing only flowers and no fruit, and worsening root rot in the apple trees. Attention should be paid to the combination of elements, and fertilization should not be one-sided, especially with trace elements. 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, causing 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 fertilizer 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 support growth. Actually, in the planting process, there are requirements for the timing of topdressing, especially during the period after harvest. Harvest usually takes place in autumn. After harvest, sufficient base fertilizer should be applied, 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 supplemented for the fruit tree in time, the fruit tree is prone to frost 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 causes the roots of the fruit trees to gradually extend only toward the upper part of the soil, so that a slight lack of water or excess water will damage the roots. The tree roots cannot breathe, the fruit trees lack nutrient supply, the tree vigor gradually weakens, and a large number of leaves fall and roots rot.

The above four points are the main causes of root rot in apple trees. Root rot in apple trees not only affects the breathing of the roots and nutrient absorption. It also threatens the growth of the fruit trees, as well as the final yield and quality. As can be seen above, the main causes are mostly related to various aspects of fertilization, so everyone should master the correct fertilization techniques and try to reduce adverse situations to a minimum. This article is for reference only, and I hope it is helpful to everyone.