Comparison Of Morphological Structure Of Root And Leaf Of Three Garden Plants Under Various Soil Water Conditions

With the development of society and the improvement of living standards,people have put forward higher requirements for the living environment.The application of garden plants is inseparable to create a superior,comfortable and beautiful living environment.The selection of beautiful and adaptable garden plants has been mentioned as an urgent position.In this study,three species of plants that have been widely used in southern garden construction in recent years,such as Ruellia simplex,Alpinia zerumbet ’Variegata’,Neomarica gracilis,are selected as the research objects.Samples were sampled from typical arid and wet environments in Guangxi college campus.The morphological and structural characteristics of the leaves and roots of the three plants in different soil conditions were analyzed by Naclo maceration and peroxyacetic acid maceration,paraffin section and root scanning methods.It is expected to provide theoretical guidance for similar research and the selection and application of garden plants.The main results are as follows:1.In general,the morphological characteristics of the leaves and roots of the three plants are as follows: In an arid environment,the leaf cuticle is thicker in relative to wet environment,the stomata are mainly distributed in the lower epidermis,the leaf surface has appendages,the palisade tissue is developed,the sponge mesophyll is weak or undeveloped,the mechanical tissue is developed,and the root system is developed.In the wet environment,the evolution of the above characteristics is opposite.2.The self-regulation ability of the same plant growing in different environments showed some differences.Among the indexes of the leaf epidermis,the order of the number of indexes with extremely significant differences is Neomarica gracilis> Ruellia simplex>Alpinia zerumbet ’Variegata’.Among the indexes of the leaf blade cross-cutting structure,the order of the number is Alpinia zerumbet ’Variegata’ > Ruellia simplex> Neomarica gracilis.In the root morphology index,only two indexes of Neomarica gracilis had significant differences.3.The indicating effect of stomatal density and stomatal index is not clear.The values of stomatal density and stomatal index of Ruellia simplex and Neomarica gracilis in arid environment are higher than those in wet environment,while Alpinia zerumbet ’Variegata’show the opposite trend.It is necessary to be cautious to use stomata density as an index to measure the stress resistance of plants.4.Upper leaf epidermal cuticle,palisade tissue,total root length,and root tip number are commonly used indexes to measure plant stress resistance.In this study,the values of all plant parameters in the arid environment are greater than those in the wet environment.This is in line with most plants’ strategies to deal with environmental change.However,the change rule of other indicators is not obvious,indicating the local differences in the evolution of plants.5.Correlation analysis showed that the correlation between most indexes is extremely significant.Principal component analysis showed that the most important factor is the stomatal factor.6.The adaptability of the three plants to the environment is strong.The differences in research indexes between species and within species indicate that each plant has its adaptation mechanism to the environment.In the two environments,the order of the number of significant indexes is Ruellia simplex> Neomarica gracilis> Alpinia zerumbet ’Variegata’.It reflects that Ruellia simplex can respond to environmental changes by adjusting its own structure,but it is vulnerable to sudden and extreme environmental changes.While the stable structural characteristics of Alpinia zerumbet ’Variegata’ indicate that it has a wider ecological range and stronger adaptability.The adaptability of Neomarica gracilis to the environment is somewhere in between.