A Comparative Study on the Microstructure of the Leaves of Different Pyrus ussuriensis Maxim. Cultivars

Abstract Through scanning electron microscope and optical microscope, a comparative study on morphological features and anatomical characters of the leaves of some pear cultivars (strains) was carried out. The differences of leaf structures not only affect photosynthesis, but also are the vital organs for studying the relationship among plants, which have positive effects on studying the evolution and classification of xylophyta system. in China, there have been many scholars who have already studied leaf anatomical structures and stomas of Malus Mill., Prunus avium, Citrus reticulata Blanco, and Ananas comosus (Linn.) Merr., etc., based on the research on stomas, it was shown that there were correlations between stomas and plant growth potential, resistance of plants, ploidy of chromosomes, and so on. For the materials under electron microscopy observation, 0.1 cm2 mesophyll tissues from both sides of leaf vein were got and then put Into 2.5% glutaraldehyde solution for fixing, followed by rinse with phosphate buffer, gradient dehydration with ethyl alcohol, replacement with isoamyl acetate, drying with Hitachi HCP-2 critical point dryer, embedding with JB-4 plastics and slicing with microtome, then the samples were glued on the sample table with double faced adhesive tape, and after the conductive treatment by Elko IB-3 ion sputtering equipment, the materials were observed and taken photos under HITACHIS-520 scanning electron microscope, finally the voltage was accelerated to 15 KV. The leaves of different pear cultivars (strains) in the same conditons have been observed and compared for several years, it was concluded that the leaves had obvious differences under the scanning electron microscope and optical microscope, the leaves of each cultivar had their own characteristics, mature leaves had certain stability, all these can be the reference for identifying different cultivars.