The Research On The Effect Of Light Stress On Three Pyrrosia

In the paper, Pyrrosia martinii (Christ) Ching.、Pyrrosia petiolosa and Pyrrosia porosa were chosen as the experimental materials,then using the artifical climate box to set up five different light levels. Under the light stress,the plant morphological,leaf water content, relative chlorophyll content, relative permeability of plasma membrane and chlorophyll fluorescence parameters of three Pyrrosia were determinated and analysied.The main conclusions are as follows:(1)Morphological characteristics:With increasing the degree of strong light, three kinds of Pyrrosia plants from strong to weak is in following order:Pyrrosia petiolosa、Pyrrosia martinii (Christ) Ching、Pyrrosia porosa;With increasing the degree of shade light, three kinds of Pyrrosia plants from strong to weak is in following order:Pyrrosia porosa、Pyrrosia martinii (Christ) Ching、Pyrrosia petiolosa.(2) The leaf relative water content:With increasing the degree of shade light, three kinds of Pyrrosia plants’leaf relative water content were increased. With increasing the degree of strong light, the leaf relative water content of Pyrrosia porosa leaves was decreased significantly,other two Pyrrosia leaves was increased slightly.(3) The relative chlorophyll content:With increasing the degree of shade,the relative chlorophyll content of Pyrrosia martinii (Christ) Ching. and Pyrrosia petiolosa was decreased gradually,the relative chlorophyll content of Pyrrosia porosa was firstly increased and then decreased. With increasing the degree of strong light,the relative chlorophyll content of Pyrrosia petiolosa was no significant difference, the relative chlorophyll content of Pyrrosia martinii (Christ) Ching. and Pyrrosia porosa was decreased.(4) The relative membrane permeability:With increasing the degree of shade, the relative membrane permeability of four kinds of Sedum was increased overall. With increasing the degree of strong light.the relative permeability of Pyrrosia martinii (Christ) Ching. and Pyrrosia porosa was decreased gradually, the relative permeability of Pyrrosia petiolosa was increased gradually, the relative permeability of Pyrrosia martinii (Christ) Ching.and Pyrrosiapetiolosa was increased slightly in mild strong light, and the three kinds of Pyrrosia plants’ relative membrane permeability were increased in several stronglight.(5) The chlorophyll fluorescence parameters:With increasing the degree of strong light,the Fv/Fm of Pyrrosia martinii (Christ) Ching. and Pyrrosia porosa were smaller, the Fv/Fm of Pyrrosia petiolosa did not change significantly; the Fv’/Fm’ of Pyrrosia petiolosa was increased overall, the Fv’/Fm’ of Pyrrosia martinii (Christ) Ching. and Pyrrosia porosa was decreased; the qP and ETR of Pyrrosia martinii (Christ) Ching. and Pyrrosia porosa was decreased,and the qP and ETR of Pyrrosia petiolosa was only increased in mild strong light. With increasing the degree of shade light, the Fv/Fm of three kinds of Pyrrosia did not change significantly; the Fv’/Fm’of Pyrrosia martinii (Christ) Ching. was increased, the Fv’/Fm’of Pyrrosia petiolosa was decreased,the Fv’/Fm’ of Pyrrosia porosa did not change significant;the qP and ETR of Pyrrosia petiolosa and Pyrrosia porosa was increased, the qP of Pyrrosia martinii (Christ) Ching.was decreased, the ETR of Pyrrosia martinii (Christ) Ching was increased.The research shows that The most adaptable of light is Pyrrosia petiolosa,Within the range of light intensities 600-320001ux can be normal grovth;Pyrrosia porosa are appreantly shade-tolerance,and can not normal growth in strong light;Pyrrosia martinii (Christ) Ching. can grownth in the range of light intensities 600-150001ux,but the light intensities in 320001ux,the plant can not normal growth.