Effects of nutrients and light pretreatment on phytochrome-mediated fern-spore germination |
| |
Authors: | Wolfgang Haupt |
| |
Institution: | (1) Institut für Botanik und Pharmazeutische Biologie, Universität Erlangen-Nürnberg, Schloßgarten 4, D-8520 Erlangen, Federal Republic of Germany |
| |
Abstract: | Spores of the ferns, Dryopteris filix-mas, D. paleacea and Polystichum minutum, sown on plain agar in quartz-distilled water, required several hours of red light in order to germinate. When, however, water agar was replaced by agar made up with a mineral nutrition medium, a single pulse of red light (about 1 min) was able fully to induce germination. Under these conditions spores became light-sensitive a few minutes after sowing. Thus, zero germination in dark controls was obtained only when all light was excluded immediately after sowing or when saturating far-red was given thereafter. The effect of the mineral medium was also obtained using low ion concentrations with an osmolality of less than 100 mol l–1. Thus, a specific ion effect appears more probable than an unspecific osmotic effect. Species differences in light sensitivity and in dark-germination levels, as reported in the literature, might partly be the consequence of different culture media and of light acting at a very early stage after sowing, which hitherto was assumed to be still insensitive to light. On water agar as well as on mineral agar, the inducing effect of a single red pulse could be increased by the appropriate pretreatment, i.e. by preirradiation with red light for several hours, followed by a saturating pulse of far-red, the latter abolishing the direct inducing effect of the red preirradiation. The nature of both the ion-phytochrome interaction and the phytochrome-phytochrome interaction has not yet been analysed.Abbreviations FR
saturating far-red light
- Pfr
far-red absorbin form of phytochrome
- R
broad-band red light, acting continuously during several hours
This work was performed at the Department of Plant Physiology, University of Lund, Sweden, during a sabbatical leave |
| |
Keywords: | Dryopteris Germination (fern spore phytochrome) Phytochrome (spore germination) Polystichum Pteridophyta Spore germination |
本文献已被 SpringerLink 等数据库收录! |
|