Compared responses of poplar cuttings and in vitro raised shoots to short-term chilling treatments
- 173 Downloads
In woody plants, chilling stress occurs during the early spring growth and can have important economic consequences. The aim of this study was to compare the reliability of two different experimental systems, 3-month-old softwood cuttings and in vitro-grown shoots, to study chilling effects in a poplar clone (Populus tremula×P. tremuloides cv. Muhs1). Different parameters were recorded: lignin content, sucrose concentration and protein and fresh weight variation, during a 2-week treatment at 10 °C. Two families of polypeptides of high molecular weight (110 and 116 kDa) were shown to accumulate in response to chilling in both cuttings and microshoots. For some of the parameters studied, i.e. appearance of some groups of polypeptides and reduction of fresh weight gain, both in vitro and ex vitro systems were suitable and produced similar results. In contrast, for some other observations, i.e. on sucrose concentration and lignin content, the systems led to different conclusions. While sucrose and lignin contents were shown to increase in cuttings submitted to chilling, no variation in lignin and only a small temporary peak of sucrose could be observed in microshoots kept under chilling. These parameters seem not to be suitable for studying the response of poplar in the in vitro system in such a short-term study.
Unable to display preview. Download preview PDF.