Abstract: Fifteen wild germplasm of Iris lactea Pall. var. chinensis(Fisch.) from the different habitats in the northern China under the water stress experiments in greenhouse were studied, and three different drought resistant classes were classified. Then the leaves tissue characteristic of four gremplasm were observed and analyzed in order to approve the relationship between the leaf tissue characteristic and drought resistance. The results showed that there were relationship of leaf thickness, upper and lower epidermis thickness, cutin thickness, stoma density, stockade tissue thickness, sponge tissue thickness, CTR, SR and ratio of stockade tissue thickness sponge tissue thickness among the germplasm. The stronger drought resistant germplasm with higher stoma density, thicker stockade tissue, higher CTR, lower SR, higher ratio of stockade tissue thickness sponge tissue thickness and smaller size of upper epidermis cells in leaves had stronger ability of drought resistance. The weaker drought resistant germpalsm with lower stoma density, thinner stockade tissue, lower CTR, higher SR , lower ratio of stockade tissue thickness sponge tissue thickness and bigger size of upper epidermis cells in leaves had weaker ability of drought resistance.

Key words: Iris lactea Pall. var. chinensis(Fisch.), leaf tissue structure, drought resistance