The Acid Degradation Of Plant Cell Coats System And Biological Effects

Induced the callus of Tobacco and studied the mechanism of plant cell dedifferentiation and further verified the theory of. plant cell coats system acid degradation. The morphologic varieties of Cell Coats System during the course of the inducing callus tissue were observed through the light microscope, transmission electron microscope, atomic force microscope and fluorescence microscope. The leaf explants were measured the endogenous hormones with ELISA and analyzed monosaccharide and disaccharide and polysaccharides with HPLC. This study investigated the extracellular environment conditions and the intracellular biology effects in the procession of cell dedifferentiation. The result of analyzing acid degradation of Cell Coats System of plant explants cultured in acid medium were the key factors to genesis of plant cell dedifferentiation.The two kinds of tobacco leaf blade growed in soil and culture medium respectively were cultured to induced callus. Laser scanning confocal microscope (LSCM) was adopted to detect the intracellular pH of two kinds of leaf explants and culture medium was detected by pH detection during the course of inducing callus. In this study the both pH value of culture medium was lower than normal leaf intracellular, indicating leaf explants callus tissue was induced under the acid condition. To observe the morphologic varieties of cell wall, plasma membrane and microtubule through the light microscope, transmission electron microscope, atomic force microscope and fluorescence microscope. Finding the period of time was in unison between the time when intracellular pH took place violent diversification and the genesis of acid degradation and embryo callus. To reveal a great number of intracellular H⁺ gathered in some region of cell wall and result in cell wall acid degradation to further cause acid growth.Measured the endogenous hormones content of ABA, GA₃, ZR, IAA and the rate of ABA/GA₃, and analyzed the content of monosaccharide and disaccharide and polysaccharides. Analyzed the endogenous hormones content in two kinds of leaf explants callus from different growth environment, the content and mixture ratio of endogenous hormones were one of the key factors that can affect the genesis of callus and embryo cell. As a result, the time that endogenous GA₃ involved a large increase at the beginning of induced culture was conformed to that a great decrese of intracellular pH, which showed the intracellular pH was directly affected by endogenous GA₃. The endogenous ABA also was so closely identified with intracellular pH at the end of inducing. In different callus, the content of endogenous ABA, GA₃ and the rate of endogenous ABA/GA₃ showed great positive relativity to the embryo genesis. The intense synthesis of endogenous ZR was beneficial for induced callus. But thedemand quantity to endogenous ZR would reduce when it has been induced the callus. The content of endogenous IAA in the leaf explants growed in culture medium showed positive relativity to the callus genesis. But the content of endogenous IAA in the leaf explants growed in soil was always fall. The differentiation of expression of endogenous hormone may because different growing conditions of plant leaf. The results that the increasing content of glucose and sucrose and fructose when plant cell coats system was easy to acid degradation indicated the degradation made polysaccharides separate into the monosaccharide to be absorbed easily by cell wall. Therefore cell coats system needed to be filled with glucose and sucrose in time of acid degradation.