Sublethal effects of Tibetan hulless barley on physiological and morphologic parameters in Microcystis aeruginosa
The current trend of global warming is expected to stimulate the expansion of harmful cyanobacteria blooms. Previously, the occidental type of barley straw has been used to control blooms in Europe and America, but very little is known about the antialgal abilities of its oriental relative. We tested the use of Tibetan hulless barley straw - the progenitor of oriental barley - to inhibit the growth of cyanobacterium Microcystis aeruginosa. Flow cytometry allowed assessment at single-cell level, with morphologic parameters (cell volume, cell membrane integrity) and physiological parameters (in vivo Chlorophyll a fluorescence, metabolic activity) used as endpoints. The reduction of cell densities together with integrated cell membranes suggests that Tibetan barley may act as an algistatic agent. Doses from 2.0 to 8.0 g L-1 of Tibetan barley straw efficiently inhibited the alga, but these doses were much higher than those of occidental barley. Such a large dosage introduced additional nutrients, which stimulated the intracellular metabolic activity and induced two physiological subpopulations in the acute term. After mid and long-term exposure, the growth inhibition effect exceeded the stimulation effect, so that the cells’ metabolic activity and Chlorophyll a fluorescence decayed, simultaneously with shrinkage in the algal cell volume.
Xiao Xi Chen Ying-xu Liang Xin-qiang Tang Xian-jin Peng Cheng Zhang Min Fu Zhenghao
Acadamy of Water Science and Environmental Engineering, Zhejiang University,Hangzhou 310029, P.R.China
国际会议
武汉
英文
30
2011-04-05（万方平台首次上网日期，不代表论文的发表时间）