The deficiency of pumpkin is very similar to the symptoms of viral diseases, resulting in misjudgment and increasing production costs and product quality. 1. Symptoms of nitrogen deficiency: The leaves of the plants are small, the new leaves are light green and slowly turn yellow from bottom to top. The first is yellowing between the veins; the fruit set after the flower falls is less and the fruit enlarges slowly. Causes: mainly due to the application of too little organic fertilizer during the previous operation, the decrease of soil nitrogen content or nitrogen was washed away by rain; another large harvest, resulting in reduced nitrogen fertilizer content in the soil, fertilizer is not timely, but also prone to nitrogen deficiency . Control methods: According to the pumpkin's requirements of nitrogen, phosphorus, potassium and trace elements, apply organic fertilizer to prevent nitrogen deficiency. Nitrate nitrogen may be applied under low temperature conditions; when symptoms of nitrogen deficiency occur in the field, nitrogen fertilizer should be applied immediately to the roots, and foliar sprays can also be applied. 2. Symptoms of iron deficiency: New leaves and axillary buds turn yellow and white at the beginning of the plant, especially the leaves of the upper leaves, growth points, and new leaf veins are yellowed first and then gradually chlorotic; the tips of the leaves are necrotic and develop until the entire leaf is light. Yellow or white, vein tip chlorosis, appear small brown spots, easy tissue necrosis, color is not bright. Reasons: In alkaline soils, excessive phosphorus application leads to iron deficiency; when copper, manganese and other elements in the soil are too much, it will affect the absorption and utilization of iron by pumpkin, and iron deficiency symptoms will also appear. Control methods: Soil pH should be maintained between 6 and 6.5. Lime can be applied but not excessive to prevent the soil from becoming alkaline; the soil should not be too dry or too wet; the leaves should be sprayed with a 0.3% aqueous solution of ferrous sulfate. 3. Symptoms of zinc deficiency: The leaves are small and clustered. The spots first appear on both sides of the main vein, the internodes of the main stems are shortened, the leaves are small and dense, the branches are excessive, the plants are dwarfed, and they begin to fade from the middle leaves, and the edges of the leaves are yellow. Gradually brown, leaves margin dead, leaves slightly eversion or curl. Cause: Zinc deficiency symptoms are likely to occur when there is too much light or if too much phosphorus is absorbed. If the pH of the soil is too high, even if there is enough zinc in the soil, it will not be easily dissolved or absorbed. Control methods: Do not overdosed with phosphorus in the soil, but have to selectively apply acidic fertilizers to reduce the pH of the soil. Apply about 1.5 kg of zinc sulfate per acre in the field, or spray 0.2% of zinc sulfite solution. Disclaimer: Some articles in this website have been transferred from the Internet. If you are involved in third party legal rights, please inform this website. phone Palm Recognition Time Attendance Palm Recognition Time Attendance,Biometric Time Attendance System,Biometric Face Recognirion Software,Palm Recognition Temperature Face Time Attendance Chongqing Huifan Technology Co., Ltd , https://www.hfsecuritytech.com