1985 Volume 54 Issue 1 Pages 58-65
Effects of ratios of NO3/NH4 and temperature of the nutrient solution on growth of Japanese honewort (Cryptotaenia japonica Hassk.), garland chrysanthemum (Chrysanthemum coronarium L.) and welsh onion (Allium fistulosum L.) were studied on a practical scale. Ratios of NO3/NH4 in the nutrient solution were 12/0, 9/3, 6/6 and 3/9 in me/l for all vegetables. Temperature regimes of solution were 11, 18 and 25°C for Japanese honewortsand garland chrysanthemum and 14, 21 and 28°C for welsh onion.
In general, top growth of tested vegetables was increased with raising solution temperature and increasing ratio of NH4 to NO3 in the solution. However, too much high ratio of NH4 to NO3 in the solution under low solution temperature gave the possibility to cause NH4 toxicity on the early stage of growth of Japanese honewort. The combined application of NO3 and NH4 provided better condition for not only enhancing growth but also changing leaf color from light green to green or dark green and lowering NO3 content in Japanese honewort.