分类: 生物学 >> 植物学 提交时间: 2018-01-13
摘要: To assess the water use of a clumped bamboo species, we investigated water use, physiological responses, and structural changes related to culm aging in the clumped bamboo species Bambusa chungii. Anisohydric behavior was characterized by the changed leaf water potential (ΨL), constant stomatal conductance (gs), and the low stomatal sensitivity (–m) in the young (0.52) and mature groups as well as the aged group (0.41). Intercellular CO2 (Ci) was negatively related to gs, especially during the dry season (R2 = 0.62). Hydraulic conductivity (ks) decreased by 57.9% and 58.8% in the mature and aged groups. This was accompanied by a leaf area (AL) that decreased by 55.7% and 63.7% and water transport path (h) that shortened by 8.5% and 23.3% to maintain the hydraulic safety. The photosynthetic rate (An) was similar among the three age groups even during the dry season when water deficits occurred. This might be due to compensation by increased chlorophyll content (5.3% greater for the mature group) and stomata density (7.4% and 8.1% greater for the mature and aged groups). Physiological and structural regulation contributes to reproductive success for B. chungii.