ISHS Acta Horticulturae 81: Symposium on Winterhardiness in Woody Perennials
PHOSPHOLIPID CHANGES DURING HARDENING OF WINTER RAPE PLANTS |
| Authors: | E. Sikorska, A. Kacperska-Palacz |
| Abstract:
The changes in the frost tolerance and phospholipid content in the winter rape /Brassica napus L. var. o lei fera L. cv. Górczanski/ plants grown either under natural environmental conditions or in the light control rooms were studied. The effect of freezing on the phospholipid content in the leaves was also checked. The frost hardening of the winter rape plants was found to be a three stage process. During the first stage, occuring at low but positive environmental temperature, phospholipid changes do not seem to be directly related to the leaf frost tolerance. That stage of hardening is possibly related to the metabolic shifts caused by the cessation of growth. The achievement of the second level of frost tolerance /in the fully turgid leaves/ depends on the occurrence of the subfreezing temperature and is related to the phospholipid content increase. The presented results indicate that there is some "treshold" value for the phospholipid content which enables cells to tolerate the frost evoked strain. It was shown that freezing brought about the phospholipid degradation which was reversible in the slightly injuried leaves only with the relatively high phospholipid content. The third stage of hardening may overlap the second one, since it is related to the frost-induced dehydration of the cells. Transient phospholipid decrease occurring at freezing may be an important factor for the efficient migration of water from protoplast to the intercellular spaces. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
