为了比较C₄荒漠植物猪毛菜(Salsola collina)和木本猪毛菜(S. arbuscula)的抗旱结构和适应环境的光合作用特征, 在二者混生的群落中, 选择代表性植株, 采集叶片进行叶片解剖结构分析, 在自然条件下测定了二者叶片的气体交换参数。研究结果表明：猪毛菜叶片具表皮毛, 具有更发达的薄壁贮水组织;木本猪毛菜叶片具有更厚的角质层, 表皮下有1层下皮细胞, 其栅栏组织细胞较长, 排列更紧密。猪毛菜的净光合速率明显高于木本猪毛菜, 日平均值分别为21.5和15.7 μmol CO₂·m^-2·s^-1。猪毛菜的蒸腾速率也明显高于木本猪毛菜, 日平均值分别为14.9和10.2 mmol·m^-2·s^-1。猪毛菜和木本猪毛菜的水分利用效率的日平均值分别为1.39和1.53 μmol CO₂·mmol^-1H₂O, 特别是在14:00时分别为1.61和2.30 μmol CO₂·mmol^-1H₂O, 木本猪毛菜高出猪毛菜约42%。猪毛菜的光补偿点低于木本猪毛菜, 而光饱和点和光量子效率较高, 具有更低的CO₂补偿点。这表明：二者的旱生结构不同, 木本猪毛菜具有更显著的荒漠植物特征;在适于二者混生的环境下, 猪毛菜比木本猪毛菜的光合能力更强, 而木本猪毛菜的水分利用效率更高。

Aims We studied the physiological and ecological characteristics of Salsola collina and S. arbuscula in order to provide a theoretical basis for understanding their physiological and ecological mechanisms of adaptation to their habitats.

Methods We chose representative plants and collected mature leaves for anatomical structure analysis, measured leaf gas exchange parameters under natural conditions in their mixed community and compared drought structures and photosynthetic characteristics of the two species.

Important findings Salsola collina leaves had epidermal hairs and more developed water storage parenchyma. Salsola arbuscula leaves had thicker cuticles with a layer of hypodermal cells under them, and the palisade cells were longer and arranged more densely. The net photosynthetic rate of S. collina was significantly higher than that of S. arbuscula, with daily mean values of 21.5 and 15.7 μmol CO₂·m^-2·s^-1, respectively. The transpiration rate of S. collina was also higher than S. arbuscula, with daily mean values of 14.9 and 10.2 mmol·m^-2·s^-1, respectively. The daily mean values of water use efficiency of S. collina and S. arbuscula were 1.39 and 1.53 μmol CO₂·mmol^-1H₂O, respectively; especially at 14:00, they were 1.61 and 2.30 μmol CO₂·mmol^-1H₂O, respectively,S. arbuscula was 42% higher than S. collina approximately. The light compensation point and CO₂ compensation point of S. collina were lower and its light saturation point and photo-quantum efficiency were higher than S. arbuscula. These findings indicate that the drought structures of the two species are different, and S. arbuscula has more desert plant features. In the community suitable for the growth of both species, the photosynthetic capacity of S. collina was stronger than S. arbuscula, and the water use efficiency of S. arbuscula was higher.