关键词: 香根草, 圆果雀稗, 光合特性, 有效光合辐射

Abstract: The experiment of different photosynthetic active radiation (PAR) was conducted to study the photosynthetic physiological characters of Vetiveria zizanioides and Paspalum orbiculare, and the differences in photosynthesis rate (Pn), transpiration rate (Tr), water use efficiency (WUE) and stomatal conductance (Gs) were also evaluated. The results showed as follows:all the Pn, Tr and Gs increased with the enhanced PAR intensity, and the Pn, Tr and Gs of Paspalum orbiculare were significantly higher than those of Vetiveria zizanioides. But WUE of Vetiveria zizanioides was higher than WUE of Paspalum orbiculare,it indicating that Vetiveria zizanioides is dominant species and Paspalum orbiculare is merely auxiliary species.

Key words: Vetiveria zizanioides, Paspalum orbiculare, photosynthetic physiological character, photosynthetic active radiation