| 释义 |
macronutrient Plant Physiol.|ˌmækrəʊˈnjuːtrɪənt|
[f. macro- + nutrient n.]
Any of the chemical elements (as potassium, nitrogen, calcium, sulphur, phosphorus, or magnesium) which are normally taken up by plants as inorganic salts and which are required for growth and development in relatively large amounts (rather than trace amounts).
1942Bot. Gaz. CIII. 651 An extensive experiment in plant nutrition was designed in order to examine the effects of varying concentrations of macro-nutrient elements in the nutrient medium on the ascorbic-acid content of tomato fruits. 1970Nature 25 July 376/1 The lack of macronutrients especially N, P and K, and sometimes micronutrients. |