Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on develop...Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on development and life cycle of this alga hinder the development of techniques for the sporeings and cultivation. In this study, internal structure of oogonium and antherium of S. babingtonii was observed with hematoxylin and eosin staining and through microscope. Meanwhile, early development from zygotes to juvenile sporelings was studied at 20℃ under 60–100 μmol photons m-2 s-1. Zygotes germinated and divided into thallus and rhizoid cells. The larger thallus cells further divided and developed into juvenile sporelings; while the smaller rhizoid cells divided and elongated into rhizoid hairs. These findings documented the life cycle of S. babingtonii and provided fundamental knowledge for sporeling nursery in the near future.展开更多
Lithophyllum okamurae is one of the important encrusting coralline algae,which plays important roles as primary producer,carbonate sediment builder,and habitat provider in the marine ecosystems.In this study,L.okamura...Lithophyllum okamurae is one of the important encrusting coralline algae,which plays important roles as primary producer,carbonate sediment builder,and habitat provider in the marine ecosystems.In this study,L.okamurae was collected from tropical coast of Sanya,and firstly described based on both detailed morph-anatomical characteristics and molecular studies of typic DNA sequences.The structure of the thalli of L.okamurae was pseudoparenchymatous construction with radially organized dimerous organizations in the crustose portion.The pseudoparenchymatous construction were composed of three parts,including 1 to 3 layers of epithelia cells which had flatten to round outermost walls,one layer of square or rectangular cells of the hypothallia and multiple layers of square or elongated rectangular peripheral cells.Palisade cells were observed,and the cells of the contiguous vegetative filaments were connected by secondary pit-connections with cell fusions absent.The carposporangial conceptacles,the spermatangial conceptacles,the bisporangial conceptacles and the tetrasporangial conceptacles were observed,and all these four kinds of conceptacles were uniporate.The spermatangial conceptacles were slightly convex and buried at shallow depths in the thalli tissues,and the carposporangial conceptacles and asexual conceptacles were protruding and conical.Phylogenetic studies based on DNA barcoding markers of 18 S rDNA,COI,rbc L and psb A revealed that L.okamurae clustered with the closest relation of L.atlanticum,and formed a distinct branch.Based on the comparative anatomical features and the molecular data,the detailed description of the valid species of L.okamurae was firstly given in this study to provide theoretical basis for algae resources utilization and conservation in marine ecosystems.展开更多
基金sponsored by the Shandong Agricultural Seedstock Breeding Projectthe Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China (No. 2010-1561)
文摘Silvetia babingtonii is a potentially economic brown alga for sources of food and high-value added utilization. So far, sporeling nursery and field cultivation has not been successful. The lack of knowledge on development and life cycle of this alga hinder the development of techniques for the sporeings and cultivation. In this study, internal structure of oogonium and antherium of S. babingtonii was observed with hematoxylin and eosin staining and through microscope. Meanwhile, early development from zygotes to juvenile sporelings was studied at 20℃ under 60–100 μmol photons m-2 s-1. Zygotes germinated and divided into thallus and rhizoid cells. The larger thallus cells further divided and developed into juvenile sporelings; while the smaller rhizoid cells divided and elongated into rhizoid hairs. These findings documented the life cycle of S. babingtonii and provided fundamental knowledge for sporeling nursery in the near future.
基金The Strategic Priority Research Program of the Chinese Academy Sciences under contract No.XDA13020203the Guangdong Science and Technology Project under contract No.201707010174the National Natural Science Foundation of China under contract No.41806145。
文摘Lithophyllum okamurae is one of the important encrusting coralline algae,which plays important roles as primary producer,carbonate sediment builder,and habitat provider in the marine ecosystems.In this study,L.okamurae was collected from tropical coast of Sanya,and firstly described based on both detailed morph-anatomical characteristics and molecular studies of typic DNA sequences.The structure of the thalli of L.okamurae was pseudoparenchymatous construction with radially organized dimerous organizations in the crustose portion.The pseudoparenchymatous construction were composed of three parts,including 1 to 3 layers of epithelia cells which had flatten to round outermost walls,one layer of square or rectangular cells of the hypothallia and multiple layers of square or elongated rectangular peripheral cells.Palisade cells were observed,and the cells of the contiguous vegetative filaments were connected by secondary pit-connections with cell fusions absent.The carposporangial conceptacles,the spermatangial conceptacles,the bisporangial conceptacles and the tetrasporangial conceptacles were observed,and all these four kinds of conceptacles were uniporate.The spermatangial conceptacles were slightly convex and buried at shallow depths in the thalli tissues,and the carposporangial conceptacles and asexual conceptacles were protruding and conical.Phylogenetic studies based on DNA barcoding markers of 18 S rDNA,COI,rbc L and psb A revealed that L.okamurae clustered with the closest relation of L.atlanticum,and formed a distinct branch.Based on the comparative anatomical features and the molecular data,the detailed description of the valid species of L.okamurae was firstly given in this study to provide theoretical basis for algae resources utilization and conservation in marine ecosystems.
