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Pyropia yezoensis(formerly Porphyra yezoensis)is an economically important red alga that is cultured extensively in China.The red rot disease occurs commonly during Pyropia cultivation,causing serious economic losses.An incidence of red rot disease was found in a P.yezoensis farm from mid-November to mid-December 2015 at Lianyungang,Jiangsu Province,China.Histopathological examination revealed that the naturally infected thalli were infected apparently by a pathogen,leading to red rot symptoms.The causative agent was isolated and identified as the oomycete Pythium chondricola by morphological analysis and sequence analysis of the internal transcribed spacer and cytochrome oxidase subunit 1(cox 1).In artifi cial infection experiments on the P.yezoensis blades,the P.chondricola isolate was able to cause the same characteristic histopathology seen in natural infections.P.chondricola grew well at a wide range of temperatures in the range 8-31℃,salinities at 0-45 and pH 5-9.In an orthogonal test used to determine the effects of environmental factors(temperature,salinity,and zoospore concentration)on infection,the data revealed that temperature was the most important factor to affect red rot disease development,with the optimal conditions for disease expansion being 20℃,35 salinity,and a zoospore concentration of 10^6 zoospores/mL.The results obtained from the present study prompted us to set up a comprehensive epidemiological study on Pyropia,which will provide support to maintain the healthy development of the Pyropia industry in China. 相似文献
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采用ISSR标记技术对来自不同产地的6个坛紫菜(Porphyra haitanensis)无性系和两个条斑紫菜(P.yezoensis)无性系进行了遗传差异的分析。结果表明,7条ISSR引物在8个紫菜系中共扩增出59条片段,全部表现出多态性。根据Nei等的相似性系数得出8个紫菜系间的遗传距离在0.274—0.746之间。用UPGMA方法作出的系统树中各紫菜基本上是按照产地进行聚类,从而推测紫菜的遗传差异可能与地域分布相关。本文结果也证明了ISSR与RAPD、AFLP等标记技术一样适用于紫菜的遗传多样性分析。 相似文献
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采用茚三酮试剂显色的薄层原位化学反应和抑藻活性检测方法,从龙须菜、条斑紫菜、鹿角藻和裙带菜中筛选环肽,发现龙须菜和条斑紫菜中存在具有抑藻活性的环肽。以龙须菜和条斑紫菜粉末为原料,采用硅胶柱层析和（或）硅胶薄层层析制备等方法,从龙须菜中分离到环（脯氨酸-甘氨酸）、环（丝氨酸-脯氨酸）和环（丙氨酸-色氨酸）,从条斑紫菜中纯化到环（亮氨酸-脯氨酸）和环（缬氨酸-酪氨酸）。除环（丝氨酸-脯氨酸）外,其余4种环二肽均是首次从相应大型海藻中获得。环（脯氨酸-甘氨酸）、环（亮氨酸-脯氨酸）和环（缬氨酸-酪氨酸）明显抑制了强壮前沟藻、赤潮异弯藻和球形棕囊藻的生长,对米氏凯伦藻和中肋骨条藻有选择性抑制作用。在50 μg/mL时,3种环二肽对强壮前沟藻、赤潮异弯藻和球形棕囊藻的生长抑制率≥50%（第4d）;环（脯氨酸-甘氨酸）对米氏凯伦藻以及环（亮氨酸-脯氨酸）对中肋骨条藻的生长抑制率超过或接近50%。随后,获得环二肽对赤潮微藻生长的半抑制效应浓度EC50-96h。结果表明,环（脯氨酸-甘氨酸）、环（亮氨酸-脯氨酸）和环（缬氨酸-酪氨酸）在抑制米氏凯伦藻、球形棕囊藻或赤潮异弯藻方面比重铬酸钾更有优势,有望开发为环境友好型赤潮微藻抑藻剂。 相似文献
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LIU Hongquan ) ) YU Wengong ) * DAI Jixun ) GONG Qianhong ) SHI Xiaochong ) YANG Kunfeng ) ) Institute of Marine Drugs Foods Ocean University of China Qingdao P..R.China ) College of Marine Life Sciences Ocean University of China Qingdao P..R.China 《中国海洋大学学报(英文版)》2004,3(1)
1 Introduction PorphyraisthemainobjectforalgafarmingandplaysaveryimportantroleinChinesemarineindus tries.Recently ,therehasbeenagreatlossinPor phyracultivationduetothedegenerationoftheculti var,sothereisanincreasingdemandforgoodPor phyracultivars .Theprerequisiteofthetraditionalbreed ingandbioengineeringresearchofPorphyraistheconstructionofpurelines .Traditionally ,theclassifi cationofPorphyrawasaccordingtotheirmorphologi calcharacteristics .However ,mostmorphologicalfea turesofPorphyraar… 相似文献
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ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｉｎｇｌｅｃｅｌｌｓａｎｄｐｒｏｔｏｐｌａｓｔｓｏｆＰｏｒｐｈｙｒａｇａｍｅｔｏｐｈｙｔｅｂｌａｄｅｓｃｏｕｌｄｄｅｖｅｌｏｐｉｎｔｏｐｌａｎｔｌｅｔｓｄｉ ｒｅｃｔｌｙｏｒｉｎｔｏｃａｌｌｕｓ ｌｉｋｅｃｅｌｌｓ (ＺｈａｏａｎｄＺｈａｎｇ ,1 981 ;Ｐｏｌｎｅ Ｆｕｌｌｅｒｅｔａｌ.,1 984 ;Ｃｈｅｎ ,1 989;ＷａｎｇａｎｄＹａｎ ,1 990 ;Ｇａｌｌｅｔａｌ.,1 993;Ｃｈｅｎ ,1 997;ＭｅｉａｎｄＦｅｉ,2 0 0 1 ) ,ａｎｄｔｈｅｉｒｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｕｎｄｅｒ… 相似文献
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ZHOU Wenjun LI Yun DAI Jixun 《中国海洋大学学报(英文版)》2007,6(3):299-302
Cryopreservation of Porphyra yezoensis conchocelis was conducted with cryoprotectants and a proposed pretreatment procedure and thawing methods explored. Six cryoprotectants combined by DMSO with ethylene glycol （EG）, propylene glycol （PEG）, sorbitol and sucrose were developed. The effect of prefreezing at -40℃ or -20℃ for different time durations was compared and the thawing methods were screened. It was shown that the cryoprotectant including 10% DMSO with 0.5 molL^-1 sorbitol exhibited the optimal effect. The ideal pretreatment was that conchocelis segments were stayed for 20min at -40℃ before stored in liquid nitrogen, and 40℃ water bath was proper for quick thawing. The highest recovery rate of cryopreserved P. yezoensis conchocelis reached 89.41%. 相似文献
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Pyropia yezoensis,an intertidal seaweed,experiences regular dehydration and rehydration with the tides.In this study,the responses of P.yezoensis to dehydration and rehydration under high and low CO 2 concentrations((600–700)×10-6 and(40–80)×10-6,named Group I and Group II respectively)were investigated.The thalli of Group I had a signifi cantly higher effective photosystem II quantum yield than the thalli of Group II at 71% absolute water content(AWC).There was little difference between thalli morphology,total Rubisco activity and total protein content at 100% and 71% AWC,which might be the basis for the normal performance of photosynthesis during moderate dehydration.A higher effective photosystem I quantum yield was observed in the thalli subjected to a low CO 2 concentration during moderate dehydration,which might be caused by the enhancement of cyclic electron fl ow.These results suggested that P.yezoensis can directly utilize CO 2 in ambient air during moderate dehydration. 相似文献
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条斑紫菜(Porphyra yezoensis)dbEST中筛选微卫星位点及引物种间转移扩增 总被引：9，自引：0，他引：9
采用电子查询的方法，借助Blast软件从条斑紫菜表达序列标签数据库的20979条序列中筛选微卫星位点，共发现非冗余微卫星位点211个，占整个条斑紫菜EST数据库的1．01％。其中双碱基重复微卫星位点共有35个，占查找微卫星序列总数的16．6％；三碱基微卫星有176个，占83．4％。双碱基重复微卫星中AG／CT形式最多，而三碱基中GGC／GCC最多。从筛选出的微卫星位点中选取序列设计合成引物，用在坛紫菜上进行引物种间转移扩增研究。在总共15对引物中有13对引物在两个种间都有扩增产物。结果表明，微卫星位点在这两种紫菜之间具有很高的同源性。获得的微卫星引物可用来进行种群遗传多样性研究、谱系鉴定和遗传图谱的构建。而微卫星标记的共显性可用来进行紫菜二倍体丝状体纯合性检验，为纯系紫菜品系的鉴定提供分子生物学鉴定方法。 相似文献