大型海藻龙须菜对锥状斯氏藻的光合生物控制机制  

Photosynthetic biological control mechanism of macroalgae Gracilaria lemaneiformis on Scrippsiella trochoidea

作　　者：张波[1] 唐灿 郑莉莉 胡琼[1] 蔡嘉骏 左娅 赵建刚[1] 叶长鹏[1] ZHANG Bo;TANG Can;ZHENG Lili;HU Qiong;CAI Jiajun;ZUO Ya;ZHAO Jiangang;YE Changpeng(Research Center of Hydrobiology,Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes,Jinan University,Guangzhou 510632;Aquatic Animal Epidemic Prevention Station in Huidong County,Guangdong Province,Huizhou 516399)

机构地区：[1]暨南大学水生生物研究中心,广东省教育厅富营养化和赤潮防治重点实验室,广州510632 [2]广东省惠东县水生动物防疫站,惠州516399

出　　处：《环境科学学报》2023年第7期363-372,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金重点项目(No.42030713);2019年度广东省农村科技特派员下乡发现问题凝炼科技助农项目(No.32419078);广东省自然科学基金(No.2020A1515011073);广州市科技计划项目2023年度农业和社会发展科技专题重点研发计划(No.2023B03J1395);广州市科技计划项目2023年度农村科技特派员专题(No.2023E04J1036)。

摘　　要：为了探究大型海藻龙须菜(Gracilaria lemaneiformis)对锥状斯氏藻(Scrippsiella trochoidea)的光合生物控制机理,在锥状斯氏藻的培养体中加入不同浓度的龙须菜海水浸提液,通过生物量、表观放氧速率和呼吸速率、光系统Ⅱ(PSⅡ)反应中心能量变化,以及反应中心、放氧侧和电子传递链活性变化,来揭示大型海藻龙须菜对锥状斯氏藻的光合抑藻机理.结果表明:共培养3 d的实验中,添加0.6 g·L^(-1)龙须菜海水提取液对锥状斯氏藻的生长有显著促进作用,与对照组相比,藻体密度提高了15.5%;添加1.2、2.4和4.8 g·L^(-1)龙须菜海水提取液对锥状斯氏藻生长则有显著抑制作用,藻体密度分别下降了26.8%、95.1%和91.4%,化感物质对锥状斯氏藻的生长有低促高抑的效果;添加龙须菜海水浸提液能显著抑制锥状斯氏藻最大光合放氧速率和显著增加其暗呼吸作用,呈现出剂量效应,抑制效果随培养时间而减弱.龙须菜中的化感物质能破坏锥状斯氏藻PSⅡ反应中心,使得反应中心数量减少,造成反应中心潜在活力(F_(v)/F_(o))下降,放氧复合体被破坏,电子传递被抑制,进而造成了赤潮藻的消亡,表明了大型海藻龙须菜的海水浸提液在生物控制赤潮藻方面的潜力.In the present study,different concentrations of Gracilaria lemaneiformis’s seawater extractions were added to the Scrippsiella trochoidea cultures,and then physiological responses of S.trochoidea,such as biomass,photosynthetic oxygen evolution rate,respiration rate,photosynthetic efficiency of photosystem Ⅱ were determined to explore the biological control mechanisms of Gracilaria lemaneiformis on Scrippsiella trochoidea.Here,we show that while a concentration of 0.6 g·L^(-1) of G.lemaneiformis’s seawater extraction significantly enhance the growth of S.trochoidea,the concentration of 1.2,2.4 and 4.8 g·L^(-1) of seawater extractions significantly inhibit their growth after 3 days incubation.The results also showed that the seawater extraction of G.lemaneiformis significantly decrease the photosynthetic oxygen evolution rate and respiration rate of S.trochoidea,with higher inhibition rates at higher extraction concentrations.However,such an inhibitory effect was weakened within the increase of incubation time.Furthermore,our results demonstrate that the seawater extraction of G.lemaneiformis can damage the photosystem Ⅱ rection center of S.trochoidea,and then decrease the number of reaction centers,leading to a decline of photosynthetic efficiency of photosystem Ⅱ and a decrease of electron transport rate.Such a deleterious effect of G.lemaneiformis on S.trochoidea can lead to a dissipation phases of red tide induced by on S.trochoidea,suggesting a high potential of biological control of G.lemaneiformis on red tide.

关 键 词：大型海藻 龙须菜 锥状斯氏藻 光合放氧 叶绿素荧光 光系统Ⅱ(photosystemⅡ PSⅡ) 

分 类 号：X171.5[环境科学与工程—环境科学] X52