2019 ASHS Annual Conference

Snapdragon (Antirrhinum majus) is one of top ten fresh cut flowers in the United States; however, its short vase life limits its marketability. The purposes of this study were to test the effects of LED light, exogenous melatonin and AVG during the pre-harvest stage of snapdragon and investigate its possible role in improving flowers quality as well as extending their vase life. Our results showed that the treatment of 10 h white light followed by a 6 h blue light (WB) inhibited stem elongation, lengths of the inflorescences, and reduced the number of florets and vase life. On the contrary, the treatment of 10 h white light, 3 h blue light and 3 h red light (WRB) significantly promoted stem elongation and lengths of the inflorescences, increased flowers size and number of florets. The growth of stem heights and lengths of the inflorescences increased significantly in all melatonin treatments. However, quantity and size of florets were significantly increased with 200 µmol·L^-1 of melatonin treatment, and the vase life was significantly extended as well. In contrast to melatonin, all AVG treatments resulted in decreases of the floret size; and changes in stem elongation and inflorescence length were only observed in the treatment with 100 µmol·L^-1AVG. These results showed that the pre-harvest treatment with WRB light or 200 µmol·L^-1 melatonin can effectively improve the post-harvest quality of cut flowers and melatonin treatment may also extend vase life.