Abstract
In usual method of petty-tomato cultivating in NFT, the young plants were put directly on NFT bed surface, and settled at the planting panel after 10-14 days.
In this paper, a new planting method was reported and compared with the usual method. In the new method, a young plant was planted several centimeters above the surface of nutrient solution, using a piece of cloth which could absorb much nutrient solution and water the plant easily by capillary action. The effectiveness of the new planting method was evaluated early and quantitatively by plant physiological measurements.
It was cleared by plant physiological measurements with laser beam sensors that microscopic dynamics of stem diameter depended on the state of growth. That is, the young plant stem of favorable growth in new method swelled slightly during daytime on a fine day, and on the other hand, the stem of undesirable growth in usual method showed small shrinking. It was considered that these dynamics were caused by quantity of translocation and transpiration. Furthermore, it was observed that the stem diameter changed very accurately re-sponding to the fluctuations of solar radiation intensity.
Through the measuring the stem diameter physiologically and using spectrum analysis method, differences of the state of growth were explained quantitatively by sensitivity to the fluctuations of solar radiation intensity. Namely, the cross-correlation function between stem diameter and solar radiation intensity showed that stem diameter of favorable growth swelled or shrinked exactly responding to the fluctuations of solar radiation intensity with only a few minutes time lag.
