摘要
用平板划线或稀释法从湛江的凡纳滨对虾、斑节对虾、翡翠贻贝、华贵类栉孔扇贝和褐蓝子鱼肠道中分离红酵母。根据形态和碳源利用特征进行分型,利用5.8S-ITS和26S rRNA基因测序分析鉴定代表菌株,通过间歇饥饿胁迫试验,比较代表菌株对凡纳滨对虾无节Ⅵ期到溞状Ⅱ期幼体存活影响,筛选出最优菌株,进而研究目标菌株从无节Ⅵ期开始以单次低剂量、单次高剂量、多次低剂量和多次高剂量,以及只在无节Ⅳ期(提前)以单次高剂量方式投菌对幼体存活和变态的影响。研究结果显示,分离得到19株海洋红酵母,根据形态和碳源谱分为6个类型(6株代表菌编号为RY1~RY6),其中RY2、RY3、RY4和RY5均为胶红酵母,RY1和RY6分别为双倒卵形红酵母和斯鲁菲亚囊担菌。间歇饥饿胁迫下,与对照组相比,菌株RY1~RY5均能显著提高溞状Ⅱ期幼体存活率,其中RY4又显著高于其他菌株(P<0.05)。不同投菌方式下RY4对溞状期幼体存活率无显著影响(P>0.05),但提前、单次和多次3个高剂量投菌组均能显著促进溞状幼体变态(P<0.05);且营养受限条件下,糠虾Ⅰ期幼体存活率和水体酵母菌含量呈正相关。综上可得,胶红酵母较普遍存在于湛江海产经济动物肠道;菌株RY4可显著提高凡纳滨对虾幼体饥饿胁迫下的存活;对虾育苗期间多次添加高剂量或在幼体早期如无节Ⅳ期单次添加高剂量RY4,可有效促进幼体变态与营养不足时的存活。
Red yeast was isolated from the intestines of Pacific white shrimp Litopenaeus vannamei,tiger shrimp Penaeus monodon,mussel Perna viridis,scallop Mimachlamys nobilis and doctor fish Siganus fuscescens in Zhanjiang,Guangdong province,by streak plate method or dilution method,and the representative strains were identified by the 5.8 S-ITS and 26 S rRNA gene sequencing analysis after typing with the morphology and carbon source utilization characteristics.Then,the intermittent starvation stress test was conducted to compare the effect of the representative strains on survival of naupliusⅥand ZoeaⅡof Pacific white shrimp to screen the optimal strains.Furthermore,the effects of the target strain on larval survival and metamorphosis were investigated with four administration modes including single low-dose,multiple low-dosage,single high-dosage,and multiple high-dosage inoculations from naupliusⅥ,as well as single high-dosage inoculation only at naupliusⅣ(early inoculation).The results showed that a total of 19 strains of red yeast were isolated and divided into six types according to the morphology and carbon source utilization characteristics,with six representative strains(designated as RY1—RY6).RY2,RY3,RY4 and RY5 were all identified as Rhodotorula mucilaginosa,while RY1 and RY6 were referred as R.diobovata and Cystobasidium slooffiae,respertively.Under intermittent starvation test,there was significantly higher survival rate of ZoeaⅡexposed to strains RY1—RY5 than that in the control group(P<0.05),especially,significantly higher in RY4 group than in other strain groups(P<0.05).Significantly higher metamorphosis was observed in the zoea exposed to RY4 strain in three high-dose groups including the early,single,and multiply inoculation groups compared with the control group(P<0.05),without significant impact on larval survival for any of the treatment groups(P>0.05).Notably,there was a positive correlation between the larval survival of mysisⅠand the yeast content in water under nutrient restriction condition.In conclusion,strain RY4 as R.mucilaginosa generally found in guts of marine economic animals from Zhanjiang can significantly improve the survival of Pacific white shrimp larvae under starvation stress.During shrimp larviculture,inoculating RY4 at multiple high-dose or at single high-dose at the early nursing stage such as naupliusⅣcan effectively promote larval metamorphosis,and larval survival under nutrient shortage.
作者
宁为民
温崇庆
黄雪敏
柳敬旺
陈杰世
吕杰伟
梁华芳
薛明
NING Weimin;WEN Chongqing;HUANG Xuemin;LIU Jingwang;CHEN Jieshi;LYU Jiewei;LIANG Huafang;XUE Ming(Fisheries College,Guangdong Ocean University,Zhanjiang 524088,China)
出处
《水产科学》
CAS
CSCD
北大核心
2021年第1期37-45,共9页
Fisheries Science
基金
国家自然科学基金资助项目(31502189)
广东省海洋渔业科技推广专项(A201008B03,A201208B05)
广东海洋大学2019年度创新强校专项资金(230419095).
关键词
海洋红酵母
胶红酵母
鉴定
凡纳滨对虾
幼体
存活
变态
marine red yeast
Rhodotorula mucilaginosa
identification
Litopenaeus vannamei
larva
survival
metamorphosis
作者简介
宁为民(1994-),男,硕士研究生,研究方向:水产微生物学.E-mail:1635360840@qq.com;通讯作者:薛明(1975-),女,副教授,博士,研究方向:海洋和水产微生物学.E-mail:xuemtc@163.com。
