Effects of some growth stimulants on flowering and physiological reactions of Freesia (Freesia hybrida ‘Royal’)

Improving the quality and increasing flowering is one of the goals of growing bulbous flowers. It seems that plant growth stimulants depending on the type and concentration used can be effective in achieving this goal. This experiment was performed to investigate the effects of type and concentration of three growth stimuli on flowering and corm production of freesia based on a completely randomized design with three replications. Experimental treatments included three types of growth stimulants (bioradicant, Ecormon and Futop) at three levels of 0.5/1000, 1/1000 and 1.5/1000. No foliar application was considered as control treatment. The results showed that with foliar application of 1/1000 Futop, leaf length increased by 8.9% and 14.5% and leaf width by 9.8% and 5.2%, respectively, compared to the control (no foliar application). Also, in plants treated with bioradicant growth stimulant at the concentration of 1.5/1000, leaf area was higher than other treatments. The use of growth stimulants reduced flowering time. In all three growth stimuli used, an increase in flowering stem length was observed compared to the control. The use of growth stimulants in all 9 treatments was effective in increasing the number of peduncles. Using the highest concentration of growth stimulants used in this experiment, ie concentration of 1.5/1000, the diameter of the peduncle in bioradicant, ecormon and futop treatments reached 21.7, 20.6 and 23.5 mm, respectively. Bioradicant treatment at the concentration of 1.5 /1000 resulted in 2.3-fold increase in the weight of the peduncle. Total chlorophyll increased from 23.22 μg/fw in no foliar application to 31.89, 29.80 and 31.47 μg/fw at the concentration of 1.5/1000 growth stimulants of bioradicant, ecormon and futop. According to the results, different concentrations of growth stimulants caused a change in the percentage of nitrogen and phosphorus in freesia leaves. Accumulation of phosphorus in leaves treated with ecormon was more than the other growth stimulants used. In general, among the three growth stimulants used, bioradicant at the concentrations of 1 and 1.5/1000 had greater effect on the vegetative and reproductive quality of freesia.