Guava yellowing harvest is worrying, what to do?

Everyone should have experienced the anxious scene of seeing guava yellowing. In recent years, with the development of guava cultivation towards large-scale and intensive, while bringing higher economic benefits to growers, we have also received many farmers' help, and the fruit trees have grown morbidly yellow, the fruit is thin and the taste is bitter. What is the cause of guava yellowing? How to cure guava yellowing?

Guava yellowing is mainly related to three aspects: fertilizer damage, lack of nutrients and damage to the root system.

Fertilizer damage

The use of a large number of insufficiently decomposed organic fertilizers as the base fertilizer, or improper application of fertilizer, resulting in seedlings or cultivation encounters growth obstacles, the phenomenon of burning roots, yellowing, weak growth and even dead plants. Therefore, when farmers choose base fertilizer and flush fertilize, they can apply fully decomposed organic fertilizer to increase the organic matter content in the soil.

Deficiency of hormones

Guava flowers and bears fruit many times a year, with a long fruit hanging period, high yield, large nutrient consumption, and the need to absorb many trace elements. If there is a lack of trace elements such as iron and magnesium, it is easy to cause yellowing of leaves. Therefore, farmers can appropriately add an appropriate amount of medium and trace element fertilizer when applying fertilizer.

The root system is damaged

Damage to the root system of guava may be caused by too much watering and too much fertilization. In this case, the concentration of the soil solution will increase, resulting in the phenomenon of root burning, which in turn will reduce the capillary and cause guava yellowing. Another condition is caused by pests and diseases, such as guava root knot nematodes. Guava root knot nematode mainly harms the roots, stimulates the root enlargement and deformity by secreting saliva, and the ability to absorb water and fertilizer is reduced. At the same time, the wound formed by the root knot nematode hazard will cause other germs to invade, causing common infection hazards. As a result, the aboveground parts of guava infested with root-knot nematodes appear yellowing and the plants are dwarf.

To prevent guava yellowing, to do a good job in the prevention and control of guava root knot nematodes, it is recommended to use comprehensive control methods.

First, select disease-free soil seedlings, strengthen field management, and remove disease residues in a timely manner.

Second, increase the application of organic fertilizer to promote the growth of new roots and enhance the disease resistance of plants.

Third, before planting, ploughing the soil and re-infected fields can be rotated in water and drought.

Fourth, before the guava transplanting, use Yinghui nemeticide granule groove application, hole application or whole field application, the effect on nematodes for 2-3 months. If the guava is seriously damaged during growth, it is irrigated with Yinghui blue root sand mixed with water and washed.