This study aimed to explore artificial propagation techniques for Glyptosternum maculatum that is endemic in the Yarlung Zangbo River. Total 86 female fish in weight of 0.065-0.250 kg were selected, and the average we...This study aimed to explore artificial propagation techniques for Glyptosternum maculatum that is endemic in the Yarlung Zangbo River. Total 86 female fish in weight of 0.065-0.250 kg were selected, and the average weight of every 15 fish was 0.30 kg. Oxytocic drugs were injected into the base of pectoral fins of the female fish. The results showed that the total amount of female fish with artificial insemination was 59. The gloss weight of the fertilized eggs was 897.5 g with total amount of 57 440, thus the average fecundity was 1 194 eggs/fish. The fecundity showed a positive correlation with body weight （P〈0.01）. The average induction ratio and fertilization rate were 69% and 73.5%, respectively. The optimum water temperature for hatching of the fertilized eggs was 13-14 ℃ with dissolved oxygen of 6.0- 7.2 mg/L. The accumulated temperature for embryonic development of G. maculatum ranged from 2 592 to 2 916℃·h. This set of completely artificial propagation techniques has a very important significance for the artificial breeding of G. maculatum.展开更多
Persistent uplift means the Qinghai-Tibet Plateau(QTP)is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments.However,how paleogeographic and paleoclimatic events inf...Persistent uplift means the Qinghai-Tibet Plateau(QTP)is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments.However,how paleogeographic and paleoclimatic events influence the genome and population of endemic fish species remains unclear.Glyptosternon maculatum is an ancient endemic fish found on the QTP and the only critically endangered species in the Sisoridae family.Here,we found that major transposons in the G.maculatum genome showed episodic bursts,consistent with contemporaneous geological and climatic events during the QTP formation.Notably,histone genes showed significant expansion in the G.maculatum genome,which may be mediated by long interspersed nuclear elements(LINE)repetitive element duplications.Population analysis showed that ancestral G.maculatum populations experienced two significant depressions 2.6 million years ago(Mya)and 10000 years ago,exhibiting excellent synchronization with Quaternary glaciation and the Younger Dryas,respectively.Thus,we propose that paleogeography and paleoclimate were dominating driving forces for population dynamics in endemic fish on the QTP.Tectonic movements and temperature fluctuation likely destroyed the habitat and disrupted the drainage connectivity among populations.These factors may have caused severe bottlenecks and limited migration among ancestral G.maculatum populations,resulting in the low genetic diversity and endangered status of the species today.展开更多
Truffle mycelia exhibit a complex interaction pattern with host plants and have been extensively studied over the last years as a source of new bioactive compounds. Fungal enzymes possess a wide use in food industry, ...Truffle mycelia exhibit a complex interaction pattern with host plants and have been extensively studied over the last years as a source of new bioactive compounds. Fungal enzymes possess a wide use in food industry, confectionaries, textiles and leather industries in order to simplify the processing of raw materials. They are often more stable than enzymes derived from other sources. Tuber maculatum and Tuber aestivum mycelia were tested for enzymes production in Petri dishes solid medium conditions. The results showed that Tuber maculatum produced seven extracellular enzymes (amylase, xylanase, laccase, lipase, peroxidase, cellulase and catalase) while Tuber aestivum produced only three enzymes (amylase, peroxidase and catalase).展开更多
文摘This study aimed to explore artificial propagation techniques for Glyptosternum maculatum that is endemic in the Yarlung Zangbo River. Total 86 female fish in weight of 0.065-0.250 kg were selected, and the average weight of every 15 fish was 0.30 kg. Oxytocic drugs were injected into the base of pectoral fins of the female fish. The results showed that the total amount of female fish with artificial insemination was 59. The gloss weight of the fertilized eggs was 897.5 g with total amount of 57 440, thus the average fecundity was 1 194 eggs/fish. The fecundity showed a positive correlation with body weight （P〈0.01）. The average induction ratio and fertilization rate were 69% and 73.5%, respectively. The optimum water temperature for hatching of the fertilized eggs was 13-14 ℃ with dissolved oxygen of 6.0- 7.2 mg/L. The accumulated temperature for embryonic development of G. maculatum ranged from 2 592 to 2 916℃·h. This set of completely artificial propagation techniques has a very important significance for the artificial breeding of G. maculatum.
基金supported by the Key Research and Development Projects in Tibet:Preservation of Characteristic Biological Germplasm Resources and Utilization of Gene Technology in Tibet(XZ202001ZY0016N)National Natural Science Foundation of China(32072980)Special Finance of Tibet Autonomous Region(XZNKY-2019-C-053)。
文摘Persistent uplift means the Qinghai-Tibet Plateau(QTP)is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments.However,how paleogeographic and paleoclimatic events influence the genome and population of endemic fish species remains unclear.Glyptosternon maculatum is an ancient endemic fish found on the QTP and the only critically endangered species in the Sisoridae family.Here,we found that major transposons in the G.maculatum genome showed episodic bursts,consistent with contemporaneous geological and climatic events during the QTP formation.Notably,histone genes showed significant expansion in the G.maculatum genome,which may be mediated by long interspersed nuclear elements(LINE)repetitive element duplications.Population analysis showed that ancestral G.maculatum populations experienced two significant depressions 2.6 million years ago(Mya)and 10000 years ago,exhibiting excellent synchronization with Quaternary glaciation and the Younger Dryas,respectively.Thus,we propose that paleogeography and paleoclimate were dominating driving forces for population dynamics in endemic fish on the QTP.Tectonic movements and temperature fluctuation likely destroyed the habitat and disrupted the drainage connectivity among populations.These factors may have caused severe bottlenecks and limited migration among ancestral G.maculatum populations,resulting in the low genetic diversity and endangered status of the species today.
文摘Truffle mycelia exhibit a complex interaction pattern with host plants and have been extensively studied over the last years as a source of new bioactive compounds. Fungal enzymes possess a wide use in food industry, confectionaries, textiles and leather industries in order to simplify the processing of raw materials. They are often more stable than enzymes derived from other sources. Tuber maculatum and Tuber aestivum mycelia were tested for enzymes production in Petri dishes solid medium conditions. The results showed that Tuber maculatum produced seven extracellular enzymes (amylase, xylanase, laccase, lipase, peroxidase, cellulase and catalase) while Tuber aestivum produced only three enzymes (amylase, peroxidase and catalase).
