Articles
THE ROOT ACTIVITY OF FRUITING TOMATO PLANT
Root activity was determined by respiratory rate and carbohydrate status and by following the rates of salt and water uptake.
The rate of root extension growth declined considerably during the fruiting stage, reaching a minimal value at the time the first fruit ripened.
Root respiration of whole plants was determined at intervals using a respirometer devised for this purpose.
Oxygen consumption and the total non-structural carbohydrate status of the root were highest during the vegetative phase and then declined to their lowest value at the same time as the minimum rate of root extension.
The uptake of N and K increased with time over most of the experimental period, whereas the uptake of Ca and Mg and to a lesser extent Fe and P did not increase during the period with maximum fruit load.
The rate of water uptake by the roots, which increased with light intensity, was also less efficient per unit of radiation during the early fruiting stage.
Changes in water and salt uptake with time were not large and, with the exception of calcium, no serious deficiency symptoms were observed.