Question

Criteria of essentiality of nutrients element were given by

Answer 1

Criteria of essentiality of nutrient element was given by

=> Arnon and Stout

Answer 2

The criteria of essentiality of nutrient were given by 'Arnon' and 'Stout' in 1939. They stated 16 elements as the essential part of plant nutrition.

Explanation:

A element is considered  as essential element if the plant cannot complete its 'life cycle' without it. Second, the function performed by that element cannot be performed by any other element. Third, the element should directly affect the metabolism of the plant. Essential elements should not be confused with beneficial elements.