关键词: 周丛生物, 吲哚乙酸, 微生物碳代谢, 平均颜色变化率

Abstract: Periphytic biofilms are important primary producers and decomposers and play an important role in the ecosystem. This study investigated the effect of indole-3-acetic acid (IAA) on the metabolic characteristics of the periphyton microbial community from the perspective of carbon source utilization. After periphytons were cultured in greenhouse for 20 d, different concentrations of IAA  were applied. Biology ecoplates were used for the quantitative analysis of microbial carbon source utilization characteristics at the community level, the average well color development (AWCD) and multifunctional indexes were determined. The results showed that, with the increase of incubation time, AWCD of the treatments with 25, 50, 100 mg·L^-1 IAA were significantly increased, the utilization abilities to specific carbon source (e.g., carbohydrate) were changed and microbial functional diversity indexes (Shannon index, McIntosh index) were significantly increased. These results suggested that high concentration of IAA could promote the carbon metabolism activity of periphyton, and provide a foundation for intermediate culture of periphyic biofilms.

Key words: periphytic biofilms, indole-3-acetic acid (IAA), microbial carbon metabolism, average well color development (AWCD)