微量营养素（也称为痕量元素或次要营养素）是植物需要量非常小的矿质元素，但对健康生长至关重要。主要的微量营养素包括铁 (Fe)、锰 (Mn)、锌 (Zn)、铜 (Cu)、硼 (B)、钼 (Mo)、氯 (Cl) 和镍 (Ni)。尽管百万分之几的含量就足够，但任何一种微量营养素的缺乏都可能导致明显的生长障碍和产量损失。
关键事实
- Iron (Fe) is the most commonly deficient micronutrient — causes yellowing of new growth (chlorosis)
- Iron must be in chelated form (EDTA, DTPA, EDDHA) to remain soluble at higher pH
- Manganese and Zinc are required for enzyme function and photosynthesis
- Boron is critical for cell wall formation and pollen viability
- Molybdenum is needed for nitrogen metabolism — deficiency causes cupped or twisted leaves
- Micronutrient deficiencies often appear when pH is outside the 5.5–6.5 optimal range