Abstract: Atriplex is a kind of typical plant species which grows in drought and semi-drought areas around the world.In order to provide a theoretical basis of reference for its photosynthetic characteristics,a series of leaf anatomical structure,stable carbon isotope ratio(¹³ C/¹² C) and photosynthetic characteristics of seven 3-year-old Atriplex species introduced from North America were studied.The results showed that:All of the 7 Atriplex species have got Kranz anatomy and fences-like Mesophyll cell which contains bundle sheath cell inside;They can grow in both drought desert environment(Minqin in Gansu Province) and relatively humid condition(Yuanyang in Henan Province) with average δ¹³ C value from-13‰ to-16‰;The light saturation points of the 7 species were from 1 603 to 2 185 μmol·m^-2 s^-1 and the apparent quantum yields were from 0.049 5 to 0.071 8 mol CO^-2·mol^-1 photons during the growing seasons.It was concluded that the 7 Atriplex plant species belonged to C₄ plant group and their photosynthetic pathway did not change with place changing during the growing period.

Key words: Atriplex, anatomical structure, C₄ plant, photosynthetic characteristics