Mineral Nutrition In Plants of Class 11
Plants also utilize gaseous elements (C, H and O) taken directly from the atmosphere.
- Woodward (1699) : Plants obtain minerals from soil through root system.
- Liebig (1840) : Source of carbon in the plant is CO2 obtained from the atmosphere.
- Arnon and Stout (1939) : Criteria for essentiality of elements
- The plant is unable to grow normally and complete its life cycle, in the absence of the elements.
- The element is specific and cannot be replaced by another element.
- The element plays a direct role in the metabolism of the plant.
- Plant ash (obtained heating the dry plant part at 600°C) contains oxides and carbonates of elements.
- About 92 mineral elements present in different plants; 30 in each and every plant.
- Of these 30 elements, 16 elements are necessary for plant growth and are called essential elements, rest nonessential elements.