The Study On Anatomical Structure And Shade Tolerance Of Three Kinds Of Syringa Plants

Paraffin-section technique, free hand section, wood maceration, epidermis maceration and light microscopy photography were used to study on the comparative anatomical structures of three kinds of plants in Oleaceae Syringa, include Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara, Syringa oblata Lindl, and Syringa microphylla Diels, which were grew in the same environment in Changchun. Then discuss the ship of anatomical structure features and shade tolerance of these plants. The results showed that the three kinds of plants evolved different shade tolerance morphosis which proved environment effect the formation of the plant structures.From the experimental result we can find that the anticlinal wall of Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara is light sinuate. The size of stomatas are smaller and closely. The sinuate of anticlinal wall of Syringa microphylla Diels is the deepest. The size of stomatas are larger and sparse. The thickness of upper epidermis of Syringa microphylla Diels is larger than the others. The thickness of upper epidermis of Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara and Syringa oblata Lindl close to each other, but former is smaller. The thickness of lower epidermis of Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara is smaller than the others, the thickness of palisade tissue and the palisade/spongy ratio is the largest.In the petiole of Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara, there are thick cuticle on the epidermis, developed phloem fiber surround the phloem. In the petiole of Syringa oblata Lindl, more developed phloem fiber surround the phloem. There are lamellate mucus material in the epidermal cells and cortical cells. There are more developed phloem fiber and many albumin cells surround the phloem. In the petiole of Syringa microphylla Diels, thinner cuticle cover on the epidermis, there are no phloem fiber surround the phloem. There are a few of albumin cells and solitary crystal. The vessel elements arranged sparsely, and aperture sizes are variance. The xylem vessel diameter is the smallest.The data of wood anatomic structure display that, the springwood and summerwood's vessel diameter of Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara is the largest, and the Syringa microphylla Diels's is the smallest. In the wood macerations, all the vessels are simple perforation plate. Syringa oblata Lindl's vessles are the longest, there are no apparent difference on the width in the three kinds of plants. Compare these physiological index datas we could conclude that the shade tolerance of these plants are:Syringa oblata Lindl> Syringa microphylla Diels>Suringa reticulata (Blume) Hara var. mandshurica (Maxim.) Hara.