Effects of photoperiod, light intensity and water temperature on the early development of Sargassum horneri (Phaeophyta).
1995
Yoshida G. | Arima S. | Uchida T.
The early development of Sargassum horneri was observed under laboratory culture, in relation to several environmental factors: photoperiod, light intensity and water temperature. Between the five photoperiod (8 hL - 16 hD to 16 hL - 8 hD in 2 hr steps), germling growth on the basis of total leaf length was promoted with increasing daylength from 8 hL to 14 hL, however no significant difference was observed between 14 hL and 16 hL. Stem differentiation and elongation was fastest in the 12 hL -12 hD regime and delayed under longer or shorter photoperiods. Transferring young thalli to other photoperiod regimes in the course of culture also indicated that 12 hL - 12 hD highly promoted stem elongation. Germling growth was proportional to light intensities from 700 lx to 4000 lx and heavily inhibited at 700 lx. All water temperatures tested in the present study (from 15 to 25 degrees C) appear favorable for germling growth of S. horneri. The favored conditions for germling development obtained in the present study agree with field observations reported so far; young thalli grow in the summer (long daylength), and rapid stem elongation occurs after the autumnal equinox. This suggests that photoperiod and light intensity are important factors for the growth of early life stages of s. horneri.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by Wolters Kluwer