光週期和光強度對油菜品種「鳳試1001」種子發芽與植株生長之影響

Abstract

本研究以油菜品種‘鳳試1001 ’為試驗材料，探討光週期和光強度對其種子發芽與植株生長之影響，當光週期為12h（Light / Dark = 12 L / 12 D）下，在不同的光強度條件中，以125 μmol photons m^(-2) s^(-1_處理72h後，可達91%之發芽率，且其種子發芽速度較快；而在光強度設定為125 μmol photons m^(-2) s^(-1)下，於不同的光週期條件中，以Light / Dark = 6L/ 18D的處理經18h後，即可達82%之發芽率，而在36h後每一光週期之處理，其發芽率都約可達99%。恆溫25℃下，以16L / 8D的光週期處理之油菜品種‘鳳試1001 ’植株將會開花。在系列的光週期試驗中，以10 L /14 D光週期處理100d下，植株的生物量最高。本研究證實，當外在環境之時間賦予者（或時間暗示）如光週期，若能符合油菜品種‘鳳試1001 ’的內生韻律之概日週期（circadian period）約為24h，顯示可增加其生長優勢。 Rapeseed (Brassica napus L.) of Fengshan Tropical Horticultural Experiment Branch (FTHEB) of Taiwan Agricultural Research Institute, cultivar 'FTHEB 1001', was adopted for this study to investigate the effects of photoperiod and light intensity on seed germination and plant growth. In Light / Dark = 12L / 12D condition (12h cycle), germination percentage of 'FTHEB 1001' seeds reached 91% at light intensity 125 μmol photos m^(-2) s^(-1) for 72h and had a faster rate than other treatments of light intensities. At light intensity of 125 μmol photos m^(-2) s^(-1), germination percentage of 'FTHEB 1001' seeds reached to 82% in Light / Dark = 6L / 18D for 18h, the treatment better than other photoperiod settings. After 36h germination period, every treated photoperiod can reach to nearly 99% of germination percentage. In constant to 25℃, 'FTHEB 1001' will bloom under the photoperiod of 16L / 8D. The highest biomass of 'FTHEB 1001' was obtained under 10L/ 14D cycle for 100 d in this series of photoperiod experiments. Results of this study demonstrated the fact that rapeseed 'FTHEB 1001' would acquire growth advantage when the environmental Zeitgeber (or time cue; e.g. photoperiod) closely matches the circadian period (ca. 24h) of its endogenous rhythm.