留言板

尊敬的读者、作者、审稿人, 关于本刊的投稿、审稿、编辑和出版的任何问题, 您可以本页添加留言。我们将尽快给您答复。谢谢您的支持!

姓名
邮箱
手机号码
标题
留言内容
验证码

2003年  第24卷  第5期

显示方式:
研究论文
Data on 32 morphometric and seven meristic characters of 224 specimens from four currently recognized Sinibrama species in southern China were collected by using multivariate morphometrics and traditional taxonomy methods,and then analyzed with the principal component analysis for investigating morphological variations among them and evaluate their species validities.The meristic characters showed that S.affinis is clearly distinct from other congeners,and S.taeniatus is separated distinctly from S.macrops,but from S.wui to that extent that both have no overlap in the scatterplots of the first two principal components.And the specimen from the Wu Jiang and Pearl River are significantly different from each other,though they are presently reported as the same species,S.macrops,while no intraspecific variations are found among populations of S.wui.According to the morphometric characters,S.taentiatus is clearly separated from other species;S.macrops has two distinct populations,of which the Wu Jiang population is discriminated from those of S.wui and S.affins,but no difference is found between the Pearl River population of S.macrops and those of S.wui and S.affins.Above results indicate that S.taeniatus and S.affinis are two valid species;S.macrops involves two distinct species,of which the Wu Jiang population represents an unnamed species,and the Pearl River population is conspecific with S.wui.
Using the mitochondrial genomes of the muntjak (Cervidae:Muntiacus) sequenced by our lab.and 6 other species of Cetartiodactyla obtained from the GenBank,we calculated the sequence lengths and base compositions of their individual concatenated sequences of 13 amino acid sequences,13 protein-coding genes,2 rRNA genes,22 tRNA genes and control region.Sequence differences of protein-coding genes between cow/sheep,sheep/muntjak and muntjak/cow were analysed and genetic distances of the concatenated 12S rRNA and 16S rRNA genes among the 7 Cetartiodactyla species were calculated with MEGA.Based on the contatenated sequences of 13 inferred amino acid sequences of protein-coding genes,we constructed the phylogenetic tree with Neighbor-joining method,and discussed their phylogenetic relationships.Our results show:1)those species are divided into 3 clades which are a muntjak-sheep-cow clade,a pig-alpaca clade and a hippopotamus-whale clade;sheep and muntjak are first grouped into one branch and then cow is added to them;2)there is a closer relationship between muntjak and sheep than that betweeen muntjak and cow;3)the divergence between the muntjak and sheep lineages occurred at 14.7 million years ago and the one between the muntjak and cow lineages did at 16.0 million years ago.
The phylogeny of the monal pheasants (Lophophorus) and their relationships to some species of the genera Tragopan,Pucrasia and Ithaginis were studied by comparing mitochondrial cytochrome b (cyt b) nucleotide sequences.The molecular phylogenetic trees show that:1)the genus Tragopan and the genus Pucrasia share a common ancestor which is the sister taxon of the ancestor of the genus Lophophorus;2)the genus Lophophorus had evolved into two branches:One was the Sclaters Monal;the other included the Chinese Monal and the Himalayan Monal.Considering its molecular phylogeny,distribution patterns and morphological evidences,the genus Lophophorus might originate in the Hengduan mountains region of southwestern China.
Data on breeding of Little egrets (Egretta garzetta) were collected in a period from March to July of 2001 at Jiyu Island in Xiamen Egret Natural Reserve.Eggs and nestlings were marked with colors for identifying the egg-laying and hatchling sequences.Ninety one percent of clutch sizes were 4 and 5,the laying period was 7.0±1.9 d,and hatching spread was 4.2±1.4 d;the incubation time was negatively correlated with the laid order of eggs;the mass was not different for the eggs laid early or late;at early stage of development (≤5 d),nestlings were not different in growth,but a significant difference appeared after then,the rate of growth and survival was the lowest for the 5th hatchling,and the second for the 4th when counting backwards.Incubation was not continuous in laying period,and became relatively continuous after that period.By this way,the parents may regulate the incubation time,and further adjust the asynchronism of incubation,resulting in a dominance hierarchy among the nestlings,which would maximize the reproductive success.
Using a RT-PCR method,the partial cDNA sequences of heat shock protein 70 genes from three populations (Hainan,Hebei and Liaoning of China) of migratory locusts,Locusta migratoria L.were cloned and then analyzed.Under predetermined optimal reaction conditions,one fragment of 604 bp was amplified from eggs of Hebei locust population with a pair of degenerate primers (GenBank accession No.AY299637),and deduced amino acid sequence contains 201 residues.Analyzed results show that there is high homology of amino acid sequence between the migratory locust and other insects,and nucleotide sequence identity among three locust populations is 98.75% in this fragment.Therefore,it is suggested that difference of cold hardiness between different locust populations might be connected with the induced expression of heat shock protein 70,but not the cDNA sequence divergence.
From May 2001 to October 2002,the benthos were surveyed in 4 tidal zones at the intertidal zone of Jiuduansha (Shangsha,Zhongsha and Xiasha),the Yangtze River Estuary,by "Biological Survey Methods of Coastal Zone" of "Concise Regulation of National Coastal Zone and Coastal Resources Comprehensive Survey"(1986).According to their food preferences,the zoobenthos were classified into 5 ecological functional groups:planktophagous group (Pl),phytophagous group (Ph),camivorous group ?,omnivorous group (O) and detritivorous group (D).And they were measured and analyzed by classic diversity characteristic indxes.Among the total 38 species,we found crustacea with 20 species,mollusca with 12 species,polychaeta 4 species and other benthos 2 species.The numbers of each functional groups constituted the percentages of total benthos in proper order is Ph>Pl>O>D>C,and numbers of species constituted the percentages of total in proper order is Ph>O>Pl>C>D.The species diversity and species richness of each benthic functional groups were Zhongsha>Shangsha>Xiasha,Middle tidal zone>High tidal zone A (Phragmites australis) and Low tidal zone>High tidal zone B (Spartina alterniflora).The species composition of benthic functional groups had insignificant differences in Shangsha,Zhongsha and Xiasha,but they had distinct differences in each tidal zone.It verified that the structure of benthic functional groups is synthetical reflection of habitat gradient in the intertidal zone and fluctuation of natural environmental factors (Engle & Summers,1999).
The random amplified polymorphic DNA (RAPD) technique was applied to analyze intra-species differentiation among Tegillarca granosa populations distributed to the south and north of Fujian province.Samples were collected from the south (Shantou and Zhanjiang in Guangdong province) and the north (Wenling in Zhejiang province,and Korea),and defined as the representatives of the southern populations (SP),and northern populations (NP),respectively.Amplified with 20 random primers,we acquired 103 distinguished RAPD loci,ranging from 250 bp to 2500 bp in size.The least genetic distance between SP and NP was 0.3261-0.4511,while that within the populations of NP or SP was only 0.0612-0.0692.The inbreeding coefficient (Fst) between SP and NP was also larger than that within SP and NP.Using NJ and UPGMA methods,we also found the nearest phylogenetic relationship consistently occurred within the populations of the SP or NP.A significant intra-species genetic differentiation has occurred between SP and NP,probably due to the geographical isolation between the populations.
Samples of mosquitoes Culex pipiens quinquefasciatus were collected in Guangzhou,Foshan,Zhongshan in Guangdong Province in May 2001.Bioassay and starch gel electrophoresis were used to determine their resistant levels to organophosphates and BPMC,and the distribution frequency of resistant-related esterases in the 3 populations.The resistant level of the 3 populations to dichlorovos was higher than the sensitive strain of Beijing at least for 21 times,parathion for 9 times,and BPMC for 5 times.The associated A8/B8 and A9/B9 were the main highly active esterases in the 3 populations,but regional differences appeared in esterase A2/B2 and B1.It was supposed that the difference will disappeared due to gene flow.
After light and dark adaptation,the retina of the Macrobrachium rosenber was respective incubated in high calcium solution,physiological solution and low calcium solution.Soluble Gq α was extracted from the retina of the Macrobrachium rosenber with protein extract and was electophoresised by SDS-PAGE.The percent of the soluble Gq α was analyzed by Tanon GIS gel image disposal system.After the incubation in three solutions,the soluble Gq α in 42 kDa was all extracted from photoreceptor cell.The percent of the soluble Gq α in photoreceptor cell in high calcium solution,physiological solution and low calcium solution was 3.13%,3.09% and 3.03% respectively on light adaptation and was 3.17%,3.06% and 3.01% respectively on dark adaptation.In physiological solution and low calcium solution,the percent of the protein on light adaptation was higher than that on dark adaptation,but in low calcium solution,the percent of the protein on light and dark adaptation was no significantly different;in high calcium solution,the percent of the protein on dark adaptation was higher than that on light adaptation.This was probably relevant to feedback regulation.
The genus Barbodes Bleeker is a catchall group.The species assigned to this genus in China actually belong to at least four distinct genera.After comparing all the Barbodes fishes included in this research to the system used by Rainboth,reassign Barbodes fishes in China as following:1)B.baoshanensis,B.benasi and B.heterostomus are assigned to genus Neolissochilus;2)B.parvus are assigned as Discherodontus parvus;3)B.pierrei in Yunnan is conspecific with B.vernayi and B.vernayi should be assigned to the genus Hypsibarbus as Hypsibarbus vernayi;4)the remaining Barbodes fishes,B.fuxianhuensis,B.chonglingchungi,B.margarianus,B.huangchuchieni,B.cogginii (=B.daliensis),B.rhomboides,B.carinatus,B.opisthopterus and B.exiguus are assigned to genus Poropuntius.
Data on species and habitat preference of waterbirds were collected at the eastern end of Chongming Island,Shanghai,in a period form November 2002 to January 2003.Transect of 2000 m×100 m was arranged in each of five habitat types from the intertidal mudflat to that behind the sea wall.Forty-nine species was observed in 34.504 waterbirds.Of the birds,37 species and 39% of all waterbirds appeared at the algae saline transect,19 species and 6% at the bulrush outer transect,10 species and 5% at the bulrush inner transect,4 species and 3% at the reed transect,and 37 species and 47% at the transect of fish ponds with reed behind the sea wall.The highest value of species richness and abundance of wintering waterbirds in the last habitat type is a strong support to the action of ecological restoration in this island—altering low-lying paddy fields to wetlands with fish ponds and reed.
Adult northern grass lizards (Takydromus septentrionalis) were collected at Mt.Xiaohe,Hangzhou in three periods of the breeding season,2001.They were dissected to determine sex,and storages of lipids in abdominal fat bodies,carcass,tail and liver.According to the stage of egg development (non-vitellogenetic follicles,yolked follicles,and oviductal eggs),females started vitellogenesis in later March (T1),produced eggs of the first clutch in early May (T2),and partly (37% of the sex) ceased reproduction in mid-June (T3).From T1 to T2,the abdominal fat body of females decreased from 17.3 mg on average to zero,and that of males changed from 6.3 mg to 0.8 mg.The decline of the lipid in females was 3 times of that of males.However,there was no significant change in lipid contents of the carcass,tail and liver in the three periods.It is very likely that the abdominal fat body of females is used for the first clutch of eggs,and earlier production of eggs means more clutches in the season and higher reproductive success.
Baiji (Lipotes vexillifer),a fresh-water cetacean species inhabited only in China,has been living on the earth for about 25 million years.Its population size has been sharply decreasing during the past twenty years.The population size was estimated about 400 in early 1980s and down to less than 100 in late 1990s.Its habitat has also degraded drastically;it only distributes in the middle and lower reaches of the Yangtze River in China currently.Factors that threat survives of the baiji mainly come from increasingly human activities,including construction of water development projects,over-fishing and water pollution.Conservation strategies and action plans have been highlighted as follows:establishing natural reserve to protect its natural populations and habitats,setting up semi-natural reserve to conduct off-site conservation,and constructing cell or gene library to save its idioplasmic resources.Off-site conservation has been believed the most urgent action.