Study On Anatomical Structure Of Stems And Leaves Of Male And Female Plants In Three Podocarpus Plants

In this study,male and female plants of Podocarpus macrophyllus,P.macrophyllus var.maki and P.annamiensis were used as subjects.Through investigating the sections,isolation,surface microstructure,spectrum analysis and ultrastructure of their stems and leaves,gender differences in the male and female plants of different Podocarpus plants were elucidated in microstructure,and the ecological adaptation of Podocarpus plants was explored based on the variability of anatomical structure,providing a theoretical basis for the selection,promotion and further research of Podocarpus plants.The main conclusions are as follows:1.Leaf shape indexes showed significant differences among the 3 Podocarpus plants.P.annamiensis presented the maximum leaf length,leaf width,petiole length,leaf area,leaf volume and leaf mass,while P.macrophyllus var.maki showed the minimum.All leaf shape indexes of the male and female plants of P.annamiensis showed significant differences.Significant differences were also found in most leaf shape indexes in Podocarpus macrophyllus and P.macrophyllus var.maki.2.Among the structure characteristics of the 3 Podocarpus plants,the shape of the transverse section,major veins and dorsal-ventral boundary of leaves showed differences among species and between male and female plants,with reciprocal crosses different.The shape of phloem showed no differences between Podocarpus macrophyllus and P.macrophyllus var.maki,presenting an arc.Phloem of P.annamiensis in"V" shape showed significant differences with the other two species,but no obvious differences between male and female plants.3.Most anatomical indexes of leaves and all anatomical indexes of stems showed significant differences among the 3 Podocarpus plants.P.annamiensis presented the maximum palisade tissue thickness,transfusion tissue length and width,leaf thickness,P/S,CTR and stem diameter,while P.macrophyllus var.maki showed the minimum.Most anatomical indexes of stems and leaves revealed significant differences between the male and female plants of P.annamiensis and Podocarpus macrophyllus.Extremely signifcant differences were detected in medullary diameter and medullary ratio among the male and female plants of the 3 Podocarps plants.4.Most indexes of separable structure of leaves and stems showed quite significant differences among the 3 Podocarpus plants.P.annamiensis presented the maximum stomatal length,stomatal apparatus length,long cell length of upper and lower epidermis,short cell width of upper epidermis,short cell length and width of lower epidermis and pit length and width,while P.macrophyllus var.maki showed the minimum.Most indexes between the male and female plants of Podocarpus macrophyllus showed significant differences.5.Under a scanning electron microscope,stomatal apparatus of the 3 Podocarpus plants was smooth and entire with Florin ring.Wax patterns,leaf veins,leaf margins,the shape of ridges in upper epidermis,and the micromorphological structure of lower epidermis and stem epidermis showed significant differences between the male and female plants.6.Cell structure of leaves and stems showed significant differences among the 3 Podocarpus plants except for mitochondria and chloroplast length.P.annamiensis presented the maximum thickness of leaf cell wall,length and width of leaf cells,width of mitochondrion and chloroplasts,length and width of stem cells and number of stem mitochondrion,while P.macrophyllus var.maki showed the minimum.The number of chloroplasts in male leaves was all larger than that in female leaves of the 3 Podocarpus plants.7.The principal component analysis for the anatomical variability of stems and leaves revealed higher ecological adaptation in Podocarpus macrophyllus,and higher ecological adaptation in male plants than female plants of P.annamiensis and P.macrophyllus var.maki.