Abstract
Effects of solution temperature and oxygen supply into the solution on seedling growth in solution culture were studied, aiming to raising suitable seedlings used for solution culture in high planting density of tomatoes with two trusses.
At low air temperature (6°C), the growth of seedlings grown at high solution temperature (min, 17°C), as represented with stem, leaf and root length, was promoted, compaired to that at low solution temperature (min, 8°C) . There was no difference in number of leaves to the first inflorescence and days to anthesis from sowing. Low solution temperature, however, enhanced the occurrence of abnormal flowers and caused almost fruits to be malformed. Then it is desirable that air temperature should be raised at 10°C andsolution temperature at 12°C.
Aeration into the solution during the period of raising seedlings resulted in increasing top fresh weight, root dry weight and root length. The development of inflorescence, number of leaves to the first inflorescence, days to anthesis and number of flowers in the inflorescence, were hardly affected by aeration. The excess oxygen supply to the solution caused over-growth and malformed fruits such as catf aced and chucked fruits, etc. These indicate that for supplying oxygen into cultural solution in raising seedlings by solution culture in autumn to spring, mechanical aeration is not necessary and diffusing oxygen through the surface of the solution without covering the solution is recommendable.
It is expected that thus raised seedlings develop to plants producing high yield of fruits with high quality over 10 tons, when tomato plants with two trusses are cultured in the planting density of approximately 7, 000 plants per 10 a.
