Study On The Resistance And Mechanism Of Three Indoor Plants To Combined Pollution Of Formaldehyde And Benzene

Combined pollution caused by formaldehyde and benzene,the main indoor air pollutants,severely threaten people’s life safety and health.The use of plant ecological remediation technology to treat indoor air pollution has become a hot spot and frontier of research today,and the study of resistance ability and resistance mechanism of indoor plants is an important way to solve indoor air pollution.The strength of plants’resistance to pollution is the basis and prerequisite for their long-term growth and development in polluted environments,and for their sustained and stable absorption and purification capacity,but the resistance mechanism of plants to combined pollution of formaldehyde and benzene is still unclear.Therefore,Spathiphyllum kochii,Anthurium andraeanum and Sansevieria trifasciata var.laurentii were selected to conduct three replicate randomized group fumigation experiments.And the resistance ability of three indoor plants were evaluated through symptomatological observation,ANOVA and multiple comparisons,as well as the affiliation function method.The resistance mechanism of plants,through correlation analysis and principal component analysis,is therefore revealed,laying a theoretical foundation for the future selection of indoor plants with stain-resistant good dirt-absorption ability.Research shows:1.The damage symptoms of the three plants under the combined pollution of formaldehyde and benzene were obvious with the increase of the combined pollution concentration.Sansevieria trifasciata var.laurentii still grows normally,and its resistance is the strongest;Anthurium andraeanum,whose leaves turn brown and fall off,is the second most resistant;and Spathiphyllum kochii,which gradually withers and dies at the end of the test,is the least resistant.2.Subordination function value method was used to comprehensively evaluate the resistance of three plants to formaldehyde and benzene combined pollution,and the results are:Sansevieria trifasciata var.laurentii>Anthurium andraeanum>Spathiphyllum kochii.MDA（Malondialdehyde）,SP（Soluble Protein）,SS（Soluble Sugar）,POD（Peroxidase）and O₂^-（superoxide anion）in the three plant species increase with the increase of pollution concentration,while Chl increases in the opposite direction.Chl,MDA,SS,SP,POD and O₂^-in the three plants are highly affected by the pollution concentration;MDA and POD are significantly affected by the plant species,and Chl,SS,SP and O₂^-are significantly affected by the plant species;The influence of pollution concentration on plant indexes was more significant than that of plant species.3.The coefficients of O₂^-are the largest among all the indicators of the three experimental plants and could be used as the main resistance indicators;The correlations among the indicators of the three experimental plants are different,with the Chl content showing negative correlations with the other indicators to different degrees,and the rest of the indicators showing positive correlations with each other to different degrees;O₂^-,SP and SS are the main resistance indicators of Spathiphyllum kochii and Anthurium andraeanum;O₂^-,POD and SS are the main resistance indicators of Sansevieria trifasciata var.laurentii.4.The resistance mechanism of the three plants to combined pollution is the result of the interaction between each indicator.When pollution stress is applied,the main indicator O₂^-production rate increases and oxidation is strengthened;Photosynthesis was blocked and chlorophyll content decreased;MDA content increases and plants begin to self-regulate;the content of osmoregulatory substances such as SS and SP increases and reduces cell membrane plasmalogenation;Chl content increases and plants photosynthesize to produce more oxygen;POD activity increased,reducing the toxicity in the cytoplasm,the synergistic effect of the indicators to resist the stress of adversity,ensure cell viability and purify indoor air pollution.