What is the yellowing of potato leaves

Potatoes are potatoes, potatoes contain a lot of starch, starch is also the main energy intake we eat potatoes. And the protein content is also high, can promote the growth of the human body. Potato farming has become one of many people's poverty alleviation projects, but many friends do not have a correct planting method. There are many problems in the planting process, such as yellowing of leaves. So what causes the yellowing of the leaves? Let's take a look at it.

1. Late blight

Late blight is one of the common diseases of potato. The disease starts from the lower leaves after the plant is infected with late blight. Many water-like dark spots appear on the surface of the diseased leaves, and then gradually expand, and the spots merge together to form patches of different sizes. The leaf margins of the patch begin to turn yellow and develop towards the center, resulting in yellowing of the leaves. Late blight can be treated with cymoxanil, manganese and zinc, etc., with prevention as the main focus.

2. Verticillium wilt

Verticillium wilt is a soil-borne disease that attacks the roots of plants and then slowly begins to spread upward. When the roots are infected, the pathogen will destroy the vascular bundles in the plants, resulting in great obstacles to the absorption and transportation of nutrients. The plant lacks nutrients, and the leaves gradually turn yellow from the veins to yellow at last. After the disease, the growth of the plant became extremely yellow, and the whole plant showed the phenomenon of dispirited and weak, and died in the later stage.

3. Early blight

Early blight, like late blight, damages the leaves of plants, especially old leaves that are not removed in time. Infected leaves will appear in various dark spots, and then gradually expand into patches. Patchy leaves will begin to chlorinate and yellow, and eventually the whole leaf will completely chlorinate and die of dehydration. Early blight occurred at tuber swelling stage, and mancozeb was sprayed in advance to prevent it.

4. Potassium deficiency

Potatoes have a relatively high potassium requirement, and a lack of potassium during growth can cause leaf tips and margins to rot, gradually changing from green to yellow. In severe potassium deficiency, the leaves curl together as if dried by the sun and crumble with a pinch. And it will also increase the phenomenon of defoliation, which has a great impact on the growth of plants. We should timely use phosphorus and potassium power and other chemicals for spraying potassium supplement.

5. Lack of nutrition

Just said that potassium deficiency will lead to leaf yellowing, in fact, lack of various nutrients will cause this phenomenon, because potassium deficiency is more common, so I will talk about it separately. Many farmers do not control the proportion of nutrients in fertilizer reasonably when applying fertilizer, resulting in nutritional imbalance of plant growth, such as lack of nitrogen and sulfur enzymes, which will cause various abnormal conditions in leaves. If these elements are not supplemented in time, the whole plant will eventually show signs of deficiency.

The above causes several reasons for potato leaves yellowing, most of which are caused by diseases, and the threat of diseases to plants is far more than these. Yellowing leaves will reduce photosynthesis, unable to increase plant nutrient accumulation, so that tuber expansion blocked, affecting tuber quality, but also lead to their own economic interests threatened. Today's introduction is here, we must reasonably control the fertilizer nutrition ratio, in order to reduce or eliminate this phenomenon.