Acrochaete leptochaete （Huber） Nielsen （Chaetophoraceae, Chlorophyta） was isolated from the macroalgae Chaetomorpha collected from intertidal pools in Rongcheng, Shandong, China. 18S rDNA combined with ITS regions...Acrochaete leptochaete （Huber） Nielsen （Chaetophoraceae, Chlorophyta） was isolated from the macroalgae Chaetomorpha collected from intertidal pools in Rongcheng, Shandong, China. 18S rDNA combined with ITS regions were used to ascertain the morphological identification of the isolated material. Based on the unialgal culture, asexual reproduction and growth characteristics of A. leptochaete were investigated over wide ranges of temperature and irradiance. Results revealed that asexual reproduction of A. leptochaete could be realized by biflagellate zoospores. The zoospores germinated directly to give self- replicating generations. Zoospore germination was bipolar. A temperature range from 13-21 ℃ and a lower irradiance of 36 μmol/（m2.s） were most favorable for the growth ofA. leptochaete. Thallus organization, an important taxonomic criterion for the genus Acrochaete, was affected markedly by temperature and irradiance. Our results extend the knowledge about the species＇ general biology and its morphological plasticity. For classification and identification of a simple microphytic algae like A. leptochaete, which are traditionally placed in the class Chaetophoraceae, we propose that molecular tools associated with culture observations are applied.展开更多
The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphologica...The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphological characters of C. valida. Results reveal that gametophytic filaments often produce lateral branches under laboratory culture conditions, suggesting an atypical heteromorphic life cycle of C. valida between unbranched sporophytes and branched gametophytes, which differs from typical isomorphic alternation of Chaetomorpha species. The shape of the basal attachment cell, an important taxonomic character within the genus, was found variable depending on environmental conditions. The 18S rDNA and 28S rDNA regions were used to explore the phylogenetic affinity of the taxa. Inferred trees from 18S rDNA sequences revealed a close relationship between C. valida and Chaetomorpha moniligera. These results would enrich information in general biology and morphological plasticity of C. valida and provided a basis for future identification of green tide forming algae.展开更多
Acrochaete leptochaete, a species in Chaetophoraceae （Chlorophyta）, was observed during our recent laboratory culture of the macroalgae Chaetornorpha that was originally collected from an intertidal pool in Rongchen...Acrochaete leptochaete, a species in Chaetophoraceae （Chlorophyta）, was observed during our recent laboratory culture of the macroalgae Chaetornorpha that was originally collected from an intertidal pool in Rongcheng, Shandong Province, China. This is the first record of this species in China. Its morphology, taxonomy, and distribution were introduced and discussed in detail. Isolated culture experiments at different temperatures （9-29℃） and light intensities （36-108 μmol/m^2.s） were also carried out. The culture-based observations have extended our knowledge of growth morphology and general biology of the species.展开更多
Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible w...Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide.展开更多
基金Supported by the National Natural Science Foundation of China (Nos.31070185, 40876081 and 31093440)the Knowledge Innovation Program of Chinese Academy of Sciences (No. KSCX2-YW-Z-018)+6 种基金the Science and Technology Plan Project of Guangdong Province (No. 2011B031100010)the Team Project of Natural Science Foundation of Guangdong Province(No. S2011030005257)the Talent Introduction Projects of Guangdong Province Universities and Collegesthe Grant of Key Laboratory of Integrated Marine Monitoring and Applied Technologies for Harmful Algal Blooms, S.O.A., MATHAB (No. MATHAB20100301)the Science and Technology Plan Project of Shantou City (No. 2011-162)the Startup Projects (Nos. 09400133 and 09400134)the Grant for Youth Teachers of Shantou University, P. R. China
文摘Acrochaete leptochaete （Huber） Nielsen （Chaetophoraceae, Chlorophyta） was isolated from the macroalgae Chaetomorpha collected from intertidal pools in Rongcheng, Shandong, China. 18S rDNA combined with ITS regions were used to ascertain the morphological identification of the isolated material. Based on the unialgal culture, asexual reproduction and growth characteristics of A. leptochaete were investigated over wide ranges of temperature and irradiance. Results revealed that asexual reproduction of A. leptochaete could be realized by biflagellate zoospores. The zoospores germinated directly to give self- replicating generations. Zoospore germination was bipolar. A temperature range from 13-21 ℃ and a lower irradiance of 36 μmol/（m2.s） were most favorable for the growth ofA. leptochaete. Thallus organization, an important taxonomic criterion for the genus Acrochaete, was affected markedly by temperature and irradiance. Our results extend the knowledge about the species＇ general biology and its morphological plasticity. For classification and identification of a simple microphytic algae like A. leptochaete, which are traditionally placed in the class Chaetophoraceae, we propose that molecular tools associated with culture observations are applied.
基金Supported by General and Major Projects of the National Natural Science Foundation of China(Nos.31070185,31093440)the Science and Technology Project of Guangdong Province(Nos.2011B031100010,2012A020200007)+3 种基金the Talent Introduction Projects of Guangdong Province Universities and Collegesthe Team Project of Natural Science Foundation of Guangdong Province(No.S2011030005257)the Grant of the Key Laboratory of Integrated Marine Monitoring and Applied Technologies for Harmful Algal Blooms,SOA(MATHAB)(No.MATHAB20100301)the Science and Technology Project of Shantou City,China(No.2011-162)
文摘The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphological characters of C. valida. Results reveal that gametophytic filaments often produce lateral branches under laboratory culture conditions, suggesting an atypical heteromorphic life cycle of C. valida between unbranched sporophytes and branched gametophytes, which differs from typical isomorphic alternation of Chaetomorpha species. The shape of the basal attachment cell, an important taxonomic character within the genus, was found variable depending on environmental conditions. The 18S rDNA and 28S rDNA regions were used to explore the phylogenetic affinity of the taxa. Inferred trees from 18S rDNA sequences revealed a close relationship between C. valida and Chaetomorpha moniligera. These results would enrich information in general biology and morphological plasticity of C. valida and provided a basis for future identification of green tide forming algae.
基金Supported by the National Natural Science Foundation of China(Nos.40876081,30570125)the Knowledge Innovation Program of Chinese Academy of Sciences(No.KSCX2-YW-Z-018)
文摘Acrochaete leptochaete, a species in Chaetophoraceae （Chlorophyta）, was observed during our recent laboratory culture of the macroalgae Chaetornorpha that was originally collected from an intertidal pool in Rongcheng, Shandong Province, China. This is the first record of this species in China. Its morphology, taxonomy, and distribution were introduced and discussed in detail. Isolated culture experiments at different temperatures （9-29℃） and light intensities （36-108 μmol/m^2.s） were also carried out. The culture-based observations have extended our knowledge of growth morphology and general biology of the species.
基金Supported by general and major projects of National Natural Science Foundation of China (Nos 40876081,30570125,and 30499340(partly)the National High Technology Research and Development Program of China (863 Program)(No 2008BAC49B01)Knowledge Innovation Project of Chinese Academy of Sciences (No KSCX2-YW-Z-018)
文摘Combining some information from field investigation of algae along the coastal areas in China and a few pictures materialized from the western Yellow Sea in 2008,authors analyze the necessary conditions and possible water area in China producing a large biomass,some reasons for firestorm,and the possibility of the reappearance of marine bloom green alga Enteromorpha prolifera.The change of habitats and the increase of nutritional levels related to the water area could be considered as direct reasons.It was transferred northward by the combination of the flow of rainwater,wind and alongshore marine current.The original region of large biomass produced is possibly located in the southwestern Yellow sea.It will possibly be appearing again in the coming years or in the future.A summary is also given referring to its reproduction,development and distribution worldwide.
