Yellow leaf disease may be caused by the following factors.
1. Peanuts lack nitrogen
(1) Generally, in the case of insufficient soil water content, peanut leaves will not lack of nitrogen fertilizer, because peanut seedlings grow very slowly at this time. However, when the water supply is sufficient, the growth of peanut seedlings will be accelerated. At this time, there will be insufficient nitrogen supply, and the leaves will turn yellow.
(2) Applying more non decomposed farmyard manure to peanut will also lead to yellowing of leaves, which will produce harmful substances in the process of maturity of farmyard manure, hinder the extension of peanut root system, and lead to insufficient nutrient absorption and yellow leaves.
2. Iron deficiency in Peanut
(1) Iron is one of the elements that can’t be lacked in chlorophyll. If peanut is lack of iron, the upper leaves will turn yellow, and even white, but the lower leaves will keep normal green.
(2) In poor soil, the content of organic matter is relatively poor, in which nutrients are most easily lost, leading to yellowing of leaves.
3. Lack of magnesium
(1) Magnesium is also one of the elements that can’t be lacked in the composition of chlorophylls. There must be magnesium in the chlorophyll of green plants. According to some studies, magnesium can strengthen the catalysis of enzymes and is a variety of enzymes and activators.
(2) Peanuts like potassium and calcium fertilizer. If they are given enough potassium and calcium fertilizer, they will get less disease, high yield and good quality. But if they are used too much potassium and calcium fertilizer, it will also hinder the absorption of magnesium.
(3) Generally, there are more hydrogen and ammonium ions in the soil, and these ions also have antagonistic effect with magnesium, resulting in insufficient absorption of magnesium by peanut and yellow leaves.
2、 The solution to the problem of yellow leaves of peanut
1. For the yellow leaves of peanut caused by lack of nitrogen element, spraying 0.1% ferrous sulfate foliar fertilizer on the leaves after 4 p.m., spraying once every 5-7 days can quickly recover. For the yellow leaves of peanut caused by lack of iron element, ferrous sulfate can be used for seed dressing before sowing, which can effectively prevent the symptoms of iron deficiency in peanut seedling stage. When ploughing the land, about 3kg of ferrous sulfate fertilizer can be added per mu.
2. The supplement of magnesium in peanut can be sprayed with foliar fertilizer containing multiple trace elements, because magnesium is one of trace elements, and its dosage is very small, which can not be replaced by other elements. At the same time, the amount of lime should be reduced to prevent antagonistic effect on magnesium and affect the absorption and utilization of magnesium by peanut.
3. Potash fertilizer also plays a very important role in peanut production. Generally, about 20 kg per mu of land can be used, which can be used together with compound fertilizer, and the effect is better when the farm manure is sufficient.
Beijing Ronbo Sunrise Plastic Co., Ltd. – Gallon Nursery Pots/Glazed Planter/Plastic Planter/Plastic Hanging Basket/Whiskey Barrel Planter (alibaba.com)