Effect Of Stress On The Growth And Metabolism Of Dendrobium Candidium And Its Related Genetic Expression And Gene Clone

The correlation between environmental factors and the growth and metobolism of plant has nowadays become one of the hot researches in plant biology, ecobiology and biophysics. However, in terms of finding out some researches on the respects in which how various enviromental stresses would affect the growth and metabolism of plant, how plant would receive and transport the tresses signals, what is the charateristics and mechanism of responding to environmental stress stimulation in plant and how plant would regulate and adapt to the change of environmental stress, we cann't achieve some satisfactory outcomes.Dendrobium candidium Wall. ex Lindl. is an Orchidaceae epiphyte and a facultative Crassulaeean Acid Metabolism (CAM) plant, which has an good economy value of pharmaceutical. Its growth and metabolism is liable to affection of environmental factors, but the affection and the regulative mechanism on the molecular level are not reported.For the purpose of further exploring the influence of environmental stress on the plant growth and its metabolism, of investigating the mechanism and charateristics on the molecular level on the plant gene expression induced by the stress, and of searching a new way in genetics and breeding of crop. In this dissertation, using the special sound wave as a stress source and the in vitro-cultured seedlings as the experimental materials, we studied the correlation between environmental stress stimulation and the growth and metabolism of plant on the aspects of anti-oxidase system related to plant growth and metabolism, of metabolite content change, of the related enzyme gene fragment amplification, and of differentially expressed gene screening and cloning, which provided some basic evidences for the theory of stress and plant growth. The main results of this research are as follows:Firstly, the influence of sound wave stimulation on D. candidium growth had been examined, and the results showed that the in vitro-cultured seedlings would get the most obvious promotion under appropriate sound wave stress (the frequance 1000Hz, the intensity 100dB) and over these values the promotion would reduce, that is the growth of the seedlings would be inhibited. The growth rate increased when the frequence and the intensity were suitable, then we used this sound wave model to process the other experiments. By determining the activities of anti-oxidases and the contents of soluble...