OPTIMIZATION OF SOME PARAMETERS FOR ORNAMENTAL PLANTS PRODUCTION IN OFF-SEASON

The present study evaluated the behaviour of three ornamental species through flowers, in off-season cultivation conditions, in order to optimize production parameters. The total time of flowering (Ttf) was described, for each species, by mathematical models, in relation to the temperature and plants height. The biological material was represented by the species: Lathyrus odoratus L.; Antirrhinum majus L., and Matthiola incana (L.) W.T. Aiton., respectively. The variation of the plant height, in the studied ornamental species, in relation to the temperature (T), was described by polynomial equations of degree 3, in safety statistical conditions (R-2 =0.975 for Lathyrus; R-2 =0.987 for Antirrhinum, and R-2 =0.971 for Matthiola, respectively). In relation to the biological specificity and the behavior in the off-season, the three species had different values for the total time of flowering (Ttf); Ttf = 19 days for Lathyrus; Ttf=166 days for Antirrhinum, and Ttf=210 days for Matthiola. Multiple regression analysis led to the obtaining of Ttf estimation models, depending on the temperature (T, degrees C) and the height of the plants (H, cm), in statistical safety conditions. The Wolfram Alpha software facilitated the obtaining of 3D and isoquant graphic distribution models of Ttf according to T (degrees C) and H (cm), for each species studied. The optimal values for H and T were determined, in order to obtain the best total flowering time, in off-season conditions, values that can be ensured by the cultivation technology of the studied species.