Ageratum, begonia, marigold, and salvia seedlings in plug cells were stored in coolers to determine the effects of temperature, light, and storage time on growth and forcing time of seedlings after transplanting, and to determine the optimum storage temperatures for each crop. Photosynthetic photon flux densities of 0, 1, and 5 μmol·m-2.s-1 were combined with temperatures of 0.0, 2.5, 5.0, 7.5, 10.0, and 12.5C to create 18 storage environments. Sample plants were removed from each treatment at 1-week intervals for 6 weeks, and were forced into flower. In all four species, temperatures of 0.0 and 2.5C caused chilling injury and then death as plants were stored for progressively longer periods. Storage at 0.0 and 2.5C also delayed flowering when chilling injury was not severe enough to cause death. In general, plants stored better in the light than in darkness. Darkness tended to limit the time seedlings could be stored, but for each crop, the addition of just 1 μmol·m-2.s-1 extended the storage durations to 6 weeks at one or more temperatures. Storage of all four species was possible for 6 weeks, but there were significant variations between the temperatures and storage durations each species could tolerate. Optimal temperatures were 5-7.5C for begonia, 5C for marigold, and 7.5C for salvia and ageratum.
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