Which of the following elements are classified as macronutrients __________________?
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Answer: C. Ca,Mg,S
Explanation
Calcium, magnesium, and sulfur are classified as secondary macronutrients essential for healthy plant growth. Plants require these three chemical elements in moderate quantities compared to primary macronutrients like nitrogen. Each element fulfills critical structural and enzymatic roles within plant cells during vegetative development. Plant nutrients are divided into macronutrients and micronutrients based on the relative concentrations required by crops. Secondary macronutrients serve as vital components of cell walls, chlorophyll molecules, and various amino acids. Soil amendments such as agricultural lime and gypsum supply calcium and magnesium to deficient agricultural soils.
Fertilizer management programs must monitor secondary macronutrient levels to prevent hidden hunger symptoms in crops. Agronomic soil testing helps farmers apply balanced nutrient ratios to maximize agricultural yields and produce quality. Nutrient deficiencies in calcium, magnesium, or sulfur can severely impair plant development and harvest output. N, P, K represents the primary macronutrients required in the largest quantities for crop fertilization. C, H, O are structural non-mineral macronutrients derived primarily from air and water during photosynthesis. All the above is incorrect because only calcium, magnesium, and sulfur form the secondary macronutrient group.
- Subject
- Agriculture
- Category
- Agriculture
- Topic
- —
- Difficulty
- medium
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