The Realationship Between Seasonal Changes On Physiology Biochemistry And Cold Resistance In Ruta Graveolens Linn Leaves

This thesis studies on protective enzyme system,photosynthetic characteristics and osmotic adjustment function of some methods of Ruta Graveolens Linn in relation to the cold resistance during seasonal change. the result showed:With the changing seasons, the membrane permeability and the MDA content variation trends are similar in exercise group and control group of Ruta Graveolens Linn, there is no significant changes in growth period(6-8 months), but by cold hardening in September and freeze-up in November, the membrane permeability and the MDA content had a increase tendency; the content of hydrogen peroxide(H₂O₂) which variation trends are similar with the former two indexes increased. It indicated that temperature changes with seasons, hydrogen peroxide(H₂O₂) accumulation caused cell membrane injurious offense and the MDA content accretion.With the changing seasons, the activity of Catlase and Peroxidase in exercise group and control group of Ruta Graveolens Linn displayed a fluctuating. At growth period(6-8 months), there is no obvious changes. With the coming of Autumn, the acitivity of Peroxidase in exercise group and control group increased first and later decreased, but the activity of Catlase had a ascend trend. Indicated that with the extend of cold stress, two kinds of of enzymes in Ruta Graveolens Linn showed an response. With the changing seasons, by cold hardening in September, the content of soluble sugar and proline in exercise group and control group increased, compared with exercise group, the variation scope in control group was higher. The variation of soluble sugar and proline had positive significance on cold resistance.With the changing seasons, Chlorophyll (Chl) content decreased. the net photosynthetic rate(Pn) and stomatal conductance(Gs) and intercellular CO₂ concentration had different variations. At growth period(6-7 months), with the temperature increasing the net photosynthetic rate(Pn) and stomatal conductance(Gs) and intercellular CO₂ concentration had the same trend with temperature variations. It meaned the stomatal factors limited the net photosynthetic rate. At high temperature(8-9 mmonths) Pn and Gs and Ci had the opposite trend, it meaned the non-stomated factors limited net photosynthetic rate. At freeze-up(10-11 months) ,there was the same trend with high temperature(8-9 months).Our study showed that Ruta Graveolens Linn resisted the seasonal variation temperature change by means of changing membrane permeability, creasing of osmotic regulatory substance and changing the Photosynihesis. These results provide the basic data for studing the seasonal change of the physiological mechanism of Ruta Graveolens Linn in antiadversity.