Production of chrysanthemum transplants as affected by hydroponic systems, electrical conductivity in nutrient solution, and photosynthetic photon flux.

摘要

Single node cuttings of chrysanthemum (Dendranthema grandiflorum [Chrysanthemum morifolium] cv. Cheonsu) propagated in bioreactors were transferred ex vitro and acclimatized for 30 days under hydroponic systems (sand, mixed substrate consisting of peatmoss and perlite at 1:1 v/v, and deep flow technique or DFT), electrical conductivity (EC) of nutrient solution (0.8, 1.6 or 3.0 dS m-1), and photosynthetic photon flux (PPF; 50, 100 or 250 micro mol m-2 s-1). DFT and mixed substrate cultures resulted in a greater plantlet growth than sand (control), and the optimum growth was obtained with DFT. PPF and EC level had significant effects on growth enhancement. Plantlet growth increased with increasing PPF and EC level; thus, growth was most pronounced at a PPF of 250 micro mol m-2 s-1 and an EC of 3.0 dS m-1. A similar pattern was also observed in CO2 uptake rate, which started to increase after 5 days of acclimatization and became significant with a linear increase at 250 micro mol m-2 s-1 PPF combined with 3.0 dS m-1 EC until the end of acclimatization..