Anatomical structure of vegetative organs of Phalaris arundinacea L. in relation to drought resistance, waterlogging resistance and use value.

Abstract

Paraffin wax section technique was applied for microscopic observation of vegetative organs(root, stem and leaf),to study the drought and waterlogging resistance and use value of Phalaris arundinacea L.The results showed that the structure of the root,from outside to inside,was as follows:epidermis,cortex,bundle sheath,primary phloem and primary xylem.Stem was composed of epidermis,ground tissues and vascular bundles.Leaf was composed of epidermis,mesophyll cells and veins.Good ventilation organization visible in root cortex cell gaps and air cavity,primary xylem epigenetic catheter and medullary cavity were the main microscopic characteristics of waterlogging resistance.The hornificated epidermis of stem and leaves and its abundant bulliform cell groups were the main anatomical structure reasons for drought resistance.Tightly arranged mesophyll cells which contained large amounts of chloroplasts reduced transpiration and enhanced photosynthesis to ensure plant's photosynthesis even under drought conditions.A large numbers of wood fibers in vascular bundles of stem and leaves which support the plant,were major microscopic characteristics of trampling resistance.There were large areas of sclerenchyma cells in root epidermis and vascular tissues.Stem ground tissues and vascular bundles and leaves veins which were abundant in lignin and cellulose are the necessary characteristics of a new bioenergy plant.