CO_2浓度和温度升高对噬藻体PP增殖的联合作用  

The combined effects of elevated CO_2 and elevated temperature on proliferation of cyanophage PP

作　　者：牛晓莹[1] 程凯[1] 荣茜茜[1] 许敏[1] 赵以军[1] 赵进[1] 

机构地区：[1]华中师范大学城市水环境生态学湖北省重点实验室,武汉430079

出　　处：《生态学报》2012年第22期6917-6924,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金(30670088;31200385);湖北省科技攻关项目(2006AA305A04);国家科技重大专项(2009ZX07105-001)

摘　　要：在4个条件下培养了鲍氏织线藻:(1)25℃+400μmol/mol(CK组),(2)29℃+400μmol/mol(温度升高组),(3)25℃+800μmol/mol(CO2升高组),(4)29℃+800μmol/mol(温室效应组),测定了藻的生物量及细胞大小,同时用离心法测定了噬藻体PP对相应条件下宿主藻的吸附率,用一步生长曲线法测定噬藻体PP的裂解周期和释放量。结果表明,不同培养条件对藻细胞的大小均没有影响;CO2升高提高了宿主藻的生物量;温度和CO2浓度的升高不仅使噬藻体PP的裂解周期提前,而且对吸附率和释放量存在交互作用,使其发生了明显改变:其中,温度和CO2升高对噬藻体PP吸附率的影响属于协同作用,而对其释放量的影响则能够互相抵消。上述结果说明温室效应将能够导致噬藻体PP增殖能力大幅度增加。Atmospheric CO2 has increased by 25% in the past 200 years and its concentration is predicted to double by 2100.Much of the research effort into the impacts of elevated atmospheric CO2 concentrations on algae has focused on marine algae and very little work has been conducted using freshwater algae or freshwater algal viruses.Furthermore,little is known about the combined impacts of future CO2 and temperature increases on the infectivity of algal viruses,although the two impacts are closely connected.In this study,Plectonema boryanum IU597 was grown under four different conditions：（1） 25°C＋400μmol/mol CO2（control）;（2） 29°C＋400μmol/mol CO2（elevated temperature）;（3） 25°C＋800μmol/mol CO2（elevated CO2）;（4） 29°C＋800μmol/mol CO2（greenhouse effect）.The cultures were incubated for one week,one month or three months before analysis.After incubation,the biomass of each culture was measured by the Chl a labeling method and by direct counting of cell numbers.The cell size was determined by microscopy measuring,the adsorption rate of cyanophage PP was determined using the centrifugation method,and the burst size and lytic cycle were affirmed by measuring the one-step growth curve.Results indicated that different culture conditions had no significant influence on the cell size of P.boryanum.However both the elevated CO2 and the greenhouse effect conditions could significantly promote the cell number and total Chl a concentration of P.boryanum.The elevated CO2 condition also decreased the Chl a content per cell by 31.35%—42.42% compared with the control condition.The latent period of cyanophage PP was about 260 minutes under control condition,while under the elevated CO2,elevated temperature,and greenhouse effect conditions,the time was brought forward to 200,170—200,and 140 minutes,respectively.The lytic cycle of cyanophage PP was about 380 minutes under the control condition,while in the elevated CO2,elevated temperature,and greenhouse effect conditions,the time was brough

关 键 词：温室效应 噬藻体 吸附 裂解周期 释放量 

分 类 号：X173[环境科学与工程—环境科学]