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THE DEMANDS SET BY PROGRAMMED WATERING AND FEEDING ON THE GROWING MEDIUM
The programme is based on the assumption that the rate of growth is a function of radiation up to a certain level of radiation.
From this follows that the nutrient requirement of plants is also a function of radiation.
The water requirement of plants is also considered as a function of radiation.
If the amount of radiation is 100 cal/sq. cm/day, the water requirement is estimated to be 1 1/sq.m./day in full leaf cover.
In uncomplete leaf cover the water requirement is calculated in per cent from full leaf cover according to the length of the stem.
The length of the stem is considered to indicate the extent of leaf cover.
The programmed watering and feeding are based on the assumption that water and nutrients are consumed by the plants themselves.
The leaching of water and nutrients as well as the chemical and biological fixation of nutrients are supposed to be insignificant or known.
Leaching is prevented by using basin culture as culture techniques.
The growing medium in basin culture is placed on an impermeable base.