Research Of Resistance Ability And Mechanism Of Shade-tolerant Foliage Plant Under The Stress Of Indoor Benzene Pollution

Today mankind has entered the third period of pollution—indoor chemical pollution, benzene is one of "three invisible killer" of indoor air pollution, it has a strong carcinogenicity and teratogenicity and poses a serious threat on people’s lives and health. Indoor shade-tolerant foliage plants has a strong characteristic and ability to absorb, degrade, fixed and transfer pollutants, it has a security and stability, sustained and efficient purification effect of indoor benzene pollution. Houseplant ecological restoration technology has become an effective way and important means of controling indoor benzene pollution.The research selects eight kinds of common indoor shade-tolerant foliage plant which have a good purification effect of indoor chemical pollution, uses experimental design of three repeat times and randomized block, does stress test of different concentrations of benzene pollution on selected plants through the closed fumigation method, studies the resistance capability of shade-tolerant foliage plants under the stress of indoor benzene pollution through the analysis of variance, multiple comparisons and the comprehensive assessment method of membership function value of physiological and biochemical indicators of plant; Then screens six experimental plants which have the strongest resistance, reveals the reasons for its strong resistance ability through correlation and principal component analysis, studies the resistant mechanism of shade-tolerant foliage plant under the stress of indoor benzene pollution.The research result indicates:1. Research of resistance ability of shade-tolerant foliage plant under the stress of indoor benzene pollution(1) The influence differences of plant species, benzene concentration and the interaction of two factors on changes of chlorophyll and MDA content, O2·- producing rate, soluble sugar and soluble protein content, POD and APX activity and liquid pH of the experimental plants reach a highly significant level;(2) MDA and soluble protein content, O2·- producing rate, POD and APX activity of the experimental plants is on the rise, and chlorophyll and soluble sugar content, liquid pH is on the decline after the stress of different concentrations of benzene;(3) Based on the analysis of the changes of physiological and biochemical indexes and comprehensive assessment of membership function value, the results show that the shade-tolerant foliage plant which has the strongest resistance ability of the stress of benzene pollution is Sanseviera trifasciata var. laurentii, followed by Kalanchoe blossfeldiana, Chlorophytum capense var. variegatum is weakest.2. Research of resistance mechanism of shade-tolerant foliage plant under the stress of indoor benzene pollution(1) The highly negative correlation of chlorophyll content and O2·- producing rate of experiment plants weakens before unchanged, and the moderate negative correlation of chlorophyll content and soluble protein content strengthens before unchanged; The highly positive correlation of MDA content and O2·- producing rate continues to weaken; The highly positive correlation of O2·- producing rate and APX and POD activity weakens before unchanged; the moderate positive correlation of soluble protein content and APX activity remains unchanged before enhancement with the increase of benzene stress concentration.(2) MDA content, O2·- producing rate, APX activity of the first principal component of the art indicators of experimental plants are the main art indicators, and the loading constant of MDA content remains unchanged before reduction, that of O2·- producing rate remains unchanged before enhancement, that of APX activity increases before reduction with the increase of benzene stress concentration; POD activity of the second principal component is the main art indicators, and its loading constant reduces before unchanged with the increase of benzene stress concentration.(3) Based on the correlation analysis and principal component analysis of the art indicators of experimental plants, the results show that the stress of indoor benzene pollution causes direct damage of phase transition of plant biological membrane, and it also causes indirect damage to photosynthetic respiratory and indirect damage of metabolic disorders; Plant maintains resistance mainly through the scavenging effect of antioxidant enzyme system (APX, POD) on free radicals and the repair function of biological macromolecules (soluble protein) of biofilm system and the promotion of metabolism, and with the increase of the stress of benzene concentration, the former enhances before weakening, the latter enhances continuously, but the former is always plays a main role.