## Abstract The effects of hibernation and 1, 2, 4, 8, 12, 16, and 20 weeks of coldβexposure (5 Β± 1Β° C) were studied on the testes of 100 adult, male hamsters (__Mesocrietus auratus__, Waterhouse), having initial body weights of 80 to 100 gm. Half of these animals were maintained on an eightβhour p
Effect of temperature and photoperiod on the raffinose content of spruce roots
β Scribed by V. Wiemken; K. Ineichen
- Publisher
- Springer-Verlag
- Year
- 1993
- Tongue
- English
- Weight
- 538 KB
- Volume
- 190
- Category
- Article
- ISSN
- 0032-0935
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β¦ Synopsis
The influence of temperature and photoperiod on raffinose synthesis in spruce roots (Picea abies (L.) Karst.) was investigated under controlled environmental conditions in a phytotron. The raffinose content of the roots increased when the plants were subjected simultaneously to a change from long to short days and from summer-like day and night temperatures to a climate which was more than 10~ colder. Only a very slight raffinose accumulation resulted from a change of daylength or temperature alone, but a subsequent additional change of temperature or daylength, respectively, caused an increase in the raffinose content, yet only to half the amount found when both climate factors changed simultaneously. When the shoot was left under non-inducing conditions, but the root was cooled, the raffinose content increased in the root, but not in the shoot. The root was also capable of inducing raffinose if the shoot was cut off after a few days of cold adaptation of the whole plant. For all climate changes the sucrose content changed much less than the raffinose content. Induction of raffinose was comparable in mycorrhizal and in non-mycorrhizal roots.
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