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缺氮植株浅绿、基部叶片变黄,干燥时呈褐色,茎短而细,分枝少,出现早衰现象,若果树缺氮则会出现果小、果少、果皮硬等现象。缺钾茎易倒伏,叶片边缘黄化、焦枯、碎裂,脉间出现坏死斑点,整个叶片有时呈杯卷状或皱缩,褐根多。粮食类作物及其它含糖量高的作物生长后期需钾量较大,比如禾谷类和马铃薯、甘薯、西瓜、葡萄等。缺镁叶片变黄,叶脉仍绿但叶脉间变黄,有时呈紫色,并出现坏死斑点。
Nitrogen-deficient plants light green, base leaves turn yellow, brown when dry, stem short and thin, less branching, premature aging phenomenon, if the fruit tree nitrogen will appear small fruit, fruit less, hard skin and other phenomena. Potassium deficiency stem prone to lodging, leaf edge yellowing, scorch, fragmentation, necrosis spots appear between the pulse, the entire leaf sometimes cup-shaped or wrinkled, brown roots and more. Crops and other crops with high sugar content require a large amount of potassium later in life, such as cereals and potatoes, sweet potatoes, watermelons and grapes. Magnesium deficiency leaves turn yellow, veins are still green, but yellow veins, sometimes purple, and necrotic spots.