Comparison of leaf anatomical structures and epidermal features of apples grown in vitro and in field

LIANG Mei-xia; DAI Hong-yi; GE Hong-juan

Abstract：Two apple cultivars (Lujia No.5 and Ftdi) were used for the comparison of leaf anatomical structures and epider-mal features of apples grown in vitro and in field by means of conventional paraffin section and scanning electronic micro-scope.The results showed that the leaf tissues of two apple cultivars were not well developed under tissue culture conditions.There were only 1 or 2 layers of palisade tissue (s) and the ratio of P/S was less than 1.The ventral epidermal cells of leaves were irregular and their surface was smooth.The epidermal cells were combined very tightly each other and showed more sin-uous undulations.There was no trichome on dorsal surfaces of leaves.The stomata were circular and slightly protruding on dorsal epidermal cells of leaves.The leaf tissues of two apple eultivars grown in field were well developed.There were 3 pal-isade tissue layers and the ratio of P/S was more than 1.The ventral epidermal cells of leaves were roughly round and their surface was wrinkle.The cells were distributed separately.There were many trichomes in dorsal epidermal cells of leaves.The stomata were elliptical and recessed deeply in dorsal epidermal cells.The average stomata density of apple leaves grown in field was 225.42· mm~(-2)and significantly lower than that of apple grown in vitro (460.41. mm~(-2)). In different ecological circumstances,the anatomical structures and epidermal features of apple cultivars were obviously different, such as at the rate of P/S, stomata form,trichome distribution and stomatic density.