الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
as a result of long periods at high solution temperature (35 °c for 14 hours per da~) did not automatically occur,
the dry weight of those of plants grown with the NFT. With tomatoes, crop yields were intially similar for plants grown with NFT and DWC, but there was evidence that eventually more fruit would be producedby NFT grown plants, because flowers on upper inflorescences of plants grown with DWC aborted, and rate of uptake of potassium by these plants slowed down. The supply of oxygen to the submerged roots of the plants grown in DWC may have been limiting.
Experiments we needed to :- (1) determine the most appropriate method of raising seedlings, (2) ensure adequate oxygen to the roots and (3) assess the effect of the smaller change from day maximum to night minimum solution temperature than occurs with NFT.
Although day time solution temperatures were maintained at desired values, the facilities and equipment used for the experiments resulted in night time solution temperatures that were higher than planned, therefore more information is needed for plants g~own.with NFT ~nd DWC, .in an environment where not only day maximum solution temperatures can be controlled but night minimum temperatures as well.