When plants lack calcium, newly sprouted leaves and branches die easily. When they lack magnesium, they have a hard time synthesizing chlorophyll and carrying out photosynthesis to produce the nutrients they need to grow, and become much less resistant to blight.
例如植物缺鈣時，新長出的嫩葉、嫩芽容易壞死；缺鎂時則難以合成葉綠素，也沒辦法進行光合作用來取得成長所需的養分，抵抗病蟲害的能力自然跟著大幅降低。