梨树营养失调，一般可通过目视作为判断营养障碍的依据。各类缺乏营养症状的表现是：一、缺氮时叶色变黄，叶片小而硬，黄化现象普及全株，下叶位有较严重发展趋势。二、缺磷时叶片变小，叶片暗绿，有时叶柄与叶面呈紫红色。三、缺钾时老叶叶缘及尖端变黄而枯焦，并渐向内扩展 Pear tree malnutrition, generally through visual judgments as a basis for nutritional disorders. The performance of various types of lack of nutritional symptoms are: First, the nitrogen-yellow leaves turn yellow, small and hard leaves, yellow phenomenon popular throughout the plant, lower leaves bit more serious development trend. Second, the lack of phosphorus leaves smaller, dark green leaves, sometimes petioles and leaves were purple. Third, potassium deficiency when the old leaves edge and the tip yellowing and Kujiao, and gradually expanded inward