No abstract

No abstract

No abstract

We investigated the effects of a soilless culture system for use on sloping land and root-zone heating in the early morning (MH; 3:00 ～ 9:00), daytime (DH; 9:00 ～ 15:00), and 24 h constant heating (CH) on celery growth in winter. When normal drip tubes were used, solution in the tubes leaked from the lower emitters. The growth of celery plants differed with differences in the amount of fertigation. In the soilless culture system for use on sloping land, there were no leaking lines. The growth of celery plants was almost the same among all lines. Therefore, the soilless culture system is available for celery cultivation. The weight of the marketable portion grown under MH was almost the same as that of plants grown under CH and higher than that of plants grown under DH, even though the average root-zone temperature was lower than that in CH and almost the same as that in DH. The root-zone temperature in MH was lower at night than that in CH and in the morning, it was higher than that in DH. Thus, root-zone heating from morning to evening may improve celery growth. The heating cost for MH was lower than other treatments. Therefore, MH was energy efficient because the increase in the weight of marketable portion per energy consumption and per cost was the largest for MH.

No abstract