Abstract: | Abstract Using yields of plants obtained at various times of the year and from probable assumptions relative to sugar production, solute sorption, and solute distributions between roots and tops it has been deduced that both deficiencies and toxicities in mineral nutrition would be expected to be revealed earlier or more prominently in a summer season. Light is the primary determining environmental factor. The locus of nutrient deficiency revelation depends on the remobility of the element in the plant; toxic disorder is usually revealed in the oldest foliar parts. |