Numerous small rounded dark brown or black necrotic patches in green leaves; patches often in groups or rows close to midrib or major lateral veins, towards centre or basal areas of leaflects; petioles green and healthy.
Numerous small rounded dark brown or black necrotic patches in green leaves; patches often in groups or rows close to midrib or major lateral veins, towards centre or basal areas of leaflects; petioles green and healthy.
缺锰的马铃薯叶片：叶片上有大量深褐色或黑色坏死小圆斑，叶的主脉或大部分侧脉附近有条状斑纹，向叶中部和基部扩散，叶柄正常并保持绿色。