Causes and control methods of tangerine leaf curling with sugar

Sugar orange roll leaf is a common phenomenon in winter and spring, many fruit farmers will encounter this situation, some farmers do not know where to start, miss the best prevention and control period, so caused bad losses. The following editor brings you the causes of sugar orange leaf rolls and control countermeasures, along with the editor to understand it.

1. Environmental factors

It is rainy in spring, the orchard is low-lying, there is more stagnant water on the ground, and the soil water content is too much, resulting in poor breathing of sugar orange roots, thus affecting the root system to absorb water. With a long time, the leaves will curl and turn yellow because of water loss.

Prevention and control methods: dig the drainage ditch deeply, make the drainage ditch more than 80 cm from the surface, reduce the soil water content, loosen the soil, increase the oxygen content, and cover the root surface with straw or straw. reduce Rain Water's scouring of the soil on the root surface and reduce the root damage. Finally, the leaves were sprayed with brassica lipid to improve stress resistance.

2. Insect pests

Aphids cause harm to new shoots, resulting in insufficient supply of nutrients, thus affecting leaves and making them yellow and rolling leaves. In addition, summer and autumn is the peak period of red spiders, which will harm leaves, shoots and fruits, resulting in leaves yellowing and shedding.

Prevention and control methods: the harm of aphids can be sprayed with acetamiprid or other spraying to protect new shoots. Red spiders can be sprayed with sweeping mites or propargite to control red spiders.

3. Element deficiency

The biggest reason for sugar orange leaves yellowing, thinning and rolling leaves is due to nitrogen deficiency, nitrogen deficiency mainly occurs on the old leaves, the new leaves are better, the leaves as a whole yellowing, the initial nitrogen deficiency, the leaves will become light green, and then turn yellow. In addition, the lack of nitrogen fertilizer will further lead to iron deficiency in sugar orange.

Control methods: strengthen management, increase the application of organic fertilizer, if the element deficiency is serious, it can be combined with external fertilization, spray low concentration urea and potassium dihydrogen phosphate every 10 days, and add borax to fertilizer water at the same time. If there are symptoms of iron deficiency, other elements should be added to it. if it is caused by root damage, foliar fertilizer should be replenished and care should be paid to the roots of sugar tangerines.

4. Improper management

In the first year, spraying too high concentration of foliar fertilizer, plant growth regulators and pesticides on the leaves will cause some damage to the leaves, and will also cause the phenomenon of leaf curling in the second year.

Control methods: straw can be used to cover the roots to prevent sunlight damage to the roots, suspend root fertilization, wait until the new shoots are mature, adopt the principle of frequently applying thin fertilizer to promote the growth of the roots. After the new leaves unfold, but do not turn to thick green, foliar fertilizer is sprayed to absorb nutrients by roots and leaves, and promote the recovery of tree potential.

The above is the introduction of sugar orange leaf roll causes and control methods, hope to help you, want to know more related knowledge, please pay attention to us.