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A Study on Karyotypes and Ag-NORs of Odontobutis potamophila
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作者 Haihua WANG Xiandong XU +3 位作者 Wen QIU Bin WU zhiying tao Shugan ZHU 《Agricultural Biotechnology》 CAS 2018年第2期127-129,共3页
In order to obtain cytogenetic data of Odontobutis potamophila,head-kidney cells were collected as experimental materials to prepare chromosome specimen. The karyotypes of O. potamophila and the distribution and amoun... In order to obtain cytogenetic data of Odontobutis potamophila,head-kidney cells were collected as experimental materials to prepare chromosome specimen. The karyotypes of O. potamophila and the distribution and amount of transcriptionally active nucleolar organizer regions on chromosomes were analyzed by Giemsa staining and Ag-NORs. The results showed that the number of diploid chromosomes of O. potamophila was 44; the genome of O. potamophila was composed of 44 telocentric chromosomes; the karyotype formula was 2 n = 44 t,NF = 44; Ag-NORs were found in the paracentromeric region of chromosome. The results may lay the foundation for revealing the genetic pattern and chromosomal evolution of O. potamophila and contribute to further genetic breeding of O. potamophila. 展开更多
关键词 Odontobutis potamophila Karyotype Ag-NORsHomec
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Compression and shearing force on kernel rupture in shelling fresh lotus seeds 被引量:2
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作者 Jincheng He zhiying tao +1 位作者 Shihua Liang Dapeng Ye 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第1期237-242,共6页
The mechanical properties of fresh lotus seeds are still poorly understood,which complicates the design of mechanical shelling machinery.Therefore,this work carried out four-factor orthogonal tests to determine the ma... The mechanical properties of fresh lotus seeds are still poorly understood,which complicates the design of mechanical shelling machinery.Therefore,this work carried out four-factor orthogonal tests to determine the maximum permitted compressive force and minimum necessary shearing force to shell fresh lotus seeds without rupturing the kernel.It was found that the mean compression force that cracked the fresh lotus seed and led to kernel rupture was 213.03 N.Both the compressive force and the seed deformation upon kernel rupture were affected,in descending order of significance,by loading mode,seed grade,loading rate,and seed standing time.On the other hand,the shearing force needed to shell the seeds had a mean value of 7.84 N,far less than the compressive force that cracked the seed shell.The shearing force was affected,in descending order of significance,by seed standing time,tip angle of cutter blade,and loading rate,but not significantly affected by seed grade.The results suggested that mechanical shelling of fresh lotus seeds should ideally be carried out for fresh lotus seeds with a standing time of no more than 6 h using a cutter blade with an angle of about 40°at a loading rate of 30-90 mm/min. 展开更多
关键词 shelling fresh lotus seeds mechanical properties SHEARING compression kernel rupture
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Status of aquatic organisms resources and their environments in Yangtze River system(2017-2021)
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作者 Haile Yang Li Shen +104 位作者 Yongfeng He Huiwu Tian Lei Gao Jinming Wu Zhigang Mei Nian Wei Lin Wang Tingbing Zhu Feifei Hu Jinling Gong Hongchun Du Xinbin Duan Huatang Deng Daoqun Wang Fengyue Zhu Yunfeng Li Fan Wu Huijun Ru Yan Zhang Junyi Li Junlin Yang Yuntao Zhou Dongdong Fang Yinping Wang Danqing Lin Yanping Yang Peijie Li Silei Liu Jian Yang Ping Zhuang Sikai Wang tao Zhang Gang Yang Wenbo Yang Lilai Yuan Kun Cao Shuo Xu Huiyuan Liu Zhiqiang Liang Chongrui Wang Hong Li Xiping Yuan Xin Yang Yilong Fu Yanping Zhang Haixin Zhang zhiying tao Sheng Wang Xiaoping Gao Binsong Jin Kemao Li Guojie Wang Shenglong Jian Yingqin Li Chenjiang Xue Chunyun Lei Shaowei Xue Yi Sun Bin Zhu Ke Shao Xingkun Hu Meihua Xiong Jun Du Bin He tao Yan Yingying Huang Yuanchao Zou Biwen Xie Yongming Wang Bin Li Fei Liu Yaoyao Zhang Fei Fan Zhijian Wang Jing Huang Haoran Gu Hailong Ge Yan Dan Yan Li Shuqiao Wang Chuang Zhang Lu Zhou Xue Wang Sheng Zeng Yan Xiang Xugang He Jianhui Qin Chengxing Xia Jie Hou Yifu Shi Lifang Gao Zhiqiang Zhu Hongbao Shen Yun Du Xuejun Duan Jiawu Xiong Deguo Yang Shaoping Liu Zhaohui Ni Hui Zhang Kai Liu Feng Zhao Yingren Li Jianwei Wang Qiwei Wei 《Aquaculture and Fisheries》 2024年第5期833-850,共18页
The Yangtze River is the mother river of China.To promote the aquatic ecosystem protection of the great river,the Project of Yangtze Fisheries Resources and Environment Investigation(2017-2021)supported by the Ministr... The Yangtze River is the mother river of China.To promote the aquatic ecosystem protection of the great river,the Project of Yangtze Fisheries Resources and Environment Investigation(2017-2021)supported by the Ministry of Agriculture and Rural Affairs,P.R.China carried out by 24 institutes and universities that located in the Yangtze River basin surveys the status of(1)fish species composition and spatial distribution,(2)current fish abundance,(3)endangered fishes,(4)Yangtze finless porpoise,(5)aquatic eco-environments,(6)water-level fluctuation areas,(7)capture fisheries and recreational fisheries of the Yangtze River mainstream and 10 of its main tributaries,including Yalong River,Heng River,Min River(including Dadu River),Chishui River,Tuo River,Jialing River,Wu River,Han River,Dongting Lake and Poyang Lake.The results showed that there were 443 fish species(belonging to 163 genus,37 families,and 18 orders)before 2017,but only 323 fish species(including 15 new recorded exotic species)were recorded in the project of 2017-2021.Among them,Cyprinus carpio,Carassius auratus,Hypophthalmichthys molitrix,Pelteobagrus fulvidraco,Coilia brachygnathus,Silurus asotus,Saurogobio dabryi,Ctenopharyngodon idellus,Pelteobagrus nitidus,Hemiculter leucisculus,Siniperca chuatsi,Coreius heterodon,Culter alburnus,Parabramis pekinensis,and Aristichthys nobilis were the dominant species across the whole Yangtze River system.It is estimated that there were 886 million individuals weighing 124.8 million kg,merely equivalent to 27.3%of the resources in 1950s,30.9%of the resources in 1960s,or 58.7%of the resources in 1980s.In the new list of protected fishes that recorded in the Yangtze River system,only 15 of 29 were collected in this project of 2017-2021.Psephurus gladius has been affirmed to be Extinct by International Union for Conservation of Nature(IUCN).The wild individuals of Tenualosa reevesii and Luciobrama macrocephalus have disappeared for many years and maybe have been extinct already.Acipenser dabryanus has been affirmed to be Extinct in the Wild by IUCN.The natural propagations of A.sinensis,Myxocyprinus asiaticus and Trachidermus fasciatus have been interrupted for many years.The populations of Yangtze finless porpoise in the Yangtze River mainstream,Dongting Lake and Poyang Lake have steadily rising sizes and expanding distributions in 2017-2021.Parts of them migrate from one region to another with the seasons,which would result in the fluctuation of Yangtze finless porpoise population within some regions.The conventional indicators of water quality in the Yangtze River system were good and conformed to the water quality criteria of fishery in 2017-2021.In the last 40 years,the maximum surface water area in the Yangtze River basin extended to approximately 63,360 km2,the minimum surface water area covered approximately 26,396 km2,and the seasonal water-level fluctuation areas occupied approximately 36,964 km2.Compared with 1984-2000 period,the 2001-2020 period witnessed an overall decreasing trend in the frequency of surface water occurrence within about 25,869 km2 of aquatic areas.From 1984 to 2000 period to 2001-2020 period,permanent surface water has decreased by nearly 8,750 km2.In 2017,the fishermen were mainly 40-60 years old and their educational levels were mainly lower than junior high school.In 2017,most anglers were older than 40 and used hand rod and/or sea rod.Their average catch of each time was mainly less than 1 kg.Results suggested that the fishing ban in key waters of the Yangtze River basin is not only an ecological project of aquatic ecosystem conservation,but also a livelihood project for the fisherman to embrace industrial transformation and improve their living conditions.After the implementation of the fishing ban,the fisheries resources would gradually recover,and the Yangtze finless porpoise population size would also see a steady increase.However,the endangered species would remain threatened for a long time.The degraded waterbodies and water-level fluctuation areas would be the key restrictive factors for future aquatic ecosystem recovery in the Yangtze River basin.Since this survey was carried out before the fishing ban,the current results could provide a baseline for future evaluation of the effect of the Yangtze River fishing ban. 展开更多
关键词 Fishes Yangtze finless porpoise Resources Aquatic ecosystem Fisheries Background investigation Yangtze river system
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