Effect of cytokinins on the growth of vegetative shoots and flowering performance in oncidium orchids

• Main Authors: Chun-Yen Chen, 陳俊諺
• Other Authors: Kuang- Liang Huang
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/75988236922331422738

碩士 === 國立嘉義大學 === 園藝學系研究所 === 104 === Oncidium, native to Central and Southern America, have become one of Taiwan’s most important flowers. Currently, the major products of oncidium are cut-flowers and potted flowers. Due to the diversity in colors, flower types and long flowering period of potted oncidium, their domestic and exporting market demand has been increasing year by year. The purposes of this study aimed to investigate the improvement of potted flower production and regulations of flowering. For the improvement of potted flower, the effect of vegetative shoot emergence with 6-benzylamino purine ( BAP ) and kinetin ( KT ) on shoot sprowting stage ( S1 ), unsheathing stage ( S2 ) and pseudobulb mature stage ( S3 ) were investigated in Oncidesa Sweet Sugar and Oncidumnia Tdares Prettiness ‘Taichung No. 2 Purple Elfin’. This study also investigated the effects of BAP sprayed at different times on vegetative shoot emergence and growth in Oncsa. Mayfair ‘Trinity’. For the regulations of flowering, though the flowering in cut flower oncidium is the whole year long, it has the problems of intensive production periods, from May to June and September to November. To regulate flowering in December to April, the study investigated the effects of BAP at different times on vegetative shoot emergence in Oncsa. Gower Ramsey ‘Honey Angel’ and Oncsa. Gower Ramsey ‘Baby Face’ in June and August. The results showed that spraying 0.2, 0.4, 0.6 or 0.8 mM BAP on the whole plants increased the numbers of vegetative shoot in Oncsa. Sweet Sugar and Ocd. Tdares Prettiness ‘Taichung No. 2 Purple Elfin’, but spraying KT did not. In addition, the days from end of treatment to 1st floret opened hastened when sprayed with BAP on S1. However, the days from end of treatment to 1st flower opened were delayed when sprayed with BAP on S2 and S3. Two cultivars responded differently to various BAP and KT concentrations. Spraying 0.4 mM BAP on S1 or 0.4 mM KT on S3 had better vegetative shoot and inflorescence quality compared to control group in Oncsa. Sweet Sugar. For Ocd. Tdares Prettiness ‘Taichung No. 2 Purple Elfin’, the better vegetative bud and inflorescence quality were found in treatments with 0.2 mM BAP on S2 or 0.8 mM KT on S2, which were significant higher than the control ones. Meanwhile, spraying twice and three time with BAP increased the numbers of vegetative shoot in Oncsa. Mayfair ‘Trinity’. Regardless of spraying time and different concentrations, early flowering was found in Oncsa. Mayfair ‘Trinity’. When sprayed twice with BAP at concentration of 0.4 and 0.6 mM or sprayed three time with 0.2, 0.4, 0.6 and 0.8 mM BAP, the vegetative shoot and inflorescence quality were significantly better than those of the control in Oncsa. Mayfair ‘Trinity’. When sprayed twice with 0.4 and 0.8 mM BAP, the vegetative shoot and inflorescence quality of Oncsa. Gower Ramsey ‘Honey Angel’ were significantly better than those of the control group in June. For Oncsa. Gower Ramsey ‘Baby Face’, the better vegetative shoot and inflorescence quality in June were found in those plants when sprayed three time with 0.4, 0.6 or 0.8 mM BAP. Two cultivars sprayed with BAP on flowering dates were from early-January to late-January. In August, when sprayed three time with 0.6 mM BAP and 0.8 mM BAP, the vegetative shoot and inflorescence quality were significantly better than those of the control group in Oncsa. Gower Ramsey ‘Honey Angel’ and Oncsa. Gower Ramsey ‘Baby Face’. Two cultivars sprayed with BAP on flowering dates were from early-May to late-June. In conclusion, spraying BAP on the whole plants in June could change the flowering period focusing in May to June only in Taiwan, but this might not be as promising as that in August.