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1.
九种沙蜥的核型——兼论中国沙蜥属核型演化   总被引:9,自引:0,他引:9  
报道了沙蜥属9种21个不同居群的核型及银分带核型。荒漠沙蜥、草原沙蜥和斑点沙蜥2n=46=22I+24m,NF=46。叶城沙蜥2n=46=2sI+20I+24m,NF=46。南疆沙蜥、泽当沙蜥、青海沙蜥和红原沙蜥2n=48=24I+24m,NF=48。青海沙蜥具有异型性染色体。大耳沙蜥2n=48=2V+8sV+12sI+26m,NF=58。9种中,NOR均位于微小染色体对上。与本属已知核型比较,确认我国沙蜥属核型均来自共同的核型祖先,可分为3个核型类群:(1)2n=46,11对大染色体类群;(2)2n=48,12对大染色体类群;(3)大耳沙蜥。前两个类群核型与生态地理分布紧密相关。讨论了我国沙蜥属物种核型演化趋势,并结合地史资料探讨了本属核型演化与第三纪以来古地史变迁的关系。  相似文献   

2.
安徽黄精属的细胞分类学研究   总被引:10,自引:3,他引:7  
邵建章  张定成  钱枫   《广西植物》1994,14(4):361-368
本文首次报道黄精属PolygonatumMill我国三种特有植物的染色体数目和核型,结果如下:安徽黄精P.anhuiense发现两个细胞型:(1)2n=24=4m+6sm+14st;(2)2n=20=4m十6sm+10st;  黄精P.langyaensy2n=18=6m+8sm+4t;距药黄精P.franchetii有三个细胞型:(1)2n=22=8m+8sm(2sc)+6st;(2)2n=20=2m+14sm+4st;(3)2n=18=4m+8sm+4st+2T,全部属3B核型。黄精属植物安徽共有10种,本文对9种黄精的染色体数目、核型进行了比较研究,发现它们可划分成三个类群,与中国植物志(第十五卷)的形态分类基本相符。  相似文献   

3.
广西龙虎山猕猴种群生态特征   总被引:5,自引:1,他引:4  
王骏  冯敏 《兽类学报》1996,16(4):264-271
1988~1995年,采用定点观察法和绝对计数与相对计数结合法对龙虎山猕猴种群生态作了调查研究。1990年核心区有猕猴14群,500只左右,猴群密度1.6群/km2,种群密度55.6只/km2.猴群大小平均33.8±23.1(n=6)只。一般每隔4~5年分群一次,猴群群体年均增长率14.8%,种群年均增长率为9.7%。猴群中成年猴性比为7.6±6.5(n=12),1~3岁组的性比为0.74±0.61(n=4),群内未成年猴比例为67.7±3.1%(n=12)。发情交配期最早11月12日,最晚次年1月20日,高峰期12月上旬,持续3个月.产仔期最早4月1日,最晚8月14日,高峰期5月上旬,持续时间4个半月.繁殖率45.5%~100%,平均75.4±13.2%(n=21)。新生猴死亡率较低,新生猴性比(雌:雄)平均0.74±0.34(n=5)。  相似文献   

4.
卵胎生硬骨鱼褐菖You精巢的周期发育   总被引:3,自引:0,他引:3  
研究了卵胎生硬骨鱼褐菖You(Sebastiscus marmordtus)的精巢结构和生殖周期。褐菖You精巢属于小叶型。每年8~9月,精巢处于精原细胞增殖期。初级精原细胞分裂增殖,产生次级精原细胞。后者和支持细胞组成精小囊。10月~翌年、月进入精子发生期。精小囊中的生殖细胞进一步发育,逐渐形成精子。2~7月是精子退化吸收期,精巢中仅有初级精原细胞和残余的精子。在生殖季节,精子经由输出管和输精管  相似文献   

5.
四爪陆龟的活动节律   总被引:4,自引:1,他引:4  
本文报道了四爪陆龟(Testudo hosfieldi)自出蛰到入蛰过程的活动节律。四爪陆龟于3月末4月初出蛰,出蛰后的早期活动为单峰型,高峰期在13-15点钟时,活动性不强。之后直至入蛰的活动为双峰型,两峰约在上午10-12点钟和下午18-20点钟。日活动可分为转身期、日光浴期、前活动期、避暑期、后活动期和夜息期。6月末7月初开始入蛰,有的可持续到8月。自4月到8月,平均昼夜活动时间为6.7小时  相似文献   

6.
五种珍珠菜的核型研究   总被引:6,自引:2,他引:4  
本文对5种珍珠菜亚属植物进行了染色体数目及核型研究。其中瓣珍珠菜2n=24=12m+8sm+4st(2SAT)、黑腺珍珠菜2n=22=2m+4sm+6st+10t、泽珍珠菜2n=24=14m+6sm(2SAT)+4st和小叶珍珠菜2n=48=34m+10sm+4st的染色体数目及核型为首次报道。中国九江产的红根草核型2n=24=20m+4sm(2SAT)与日本产的核型2n=24=18m(1SAT)  相似文献   

7.
本文首次报道3种北美冷杉Abies amabilis、A.grandis和A.lasiocarpa的根尖体细胞核型、染色体参数及核型模式图。核型公式分别是K(2n)=24=16m(4SC)+8sm、14m(2SC)+10sm和18m(4SC)+6sm,染色体相对长度组成为2n=24=2L+12M2+6M1+4S、2L+12M2+8M1+2S和2L+8M2+12M1+2S。均为2A核型类型。文中还讨  相似文献   

8.
青海南部七种翠雀属植物的核型   总被引:1,自引:1,他引:0  
报道了采自青海南部7 种翠雀属( Delphinium L.) 植物的染色体数目和核型。大通翠雀花D.pylzowii 的核型公式为2n= 16 = 2m + 4sm + 10st; 毛翠雀花D. trichophorum 的核型公式为2n= 16 = 2m + 4sm + 10st; 蓝白翠雀花D.albocoerulum 的核型公式为2n = 16 = 2m + 4sm(2SAT) + 10st; 囊谦翠雀花D. nangchienense 的核型公式为2n = 16 = 2m + 6sm + 8st; 唐古拉翠雀花 D.tangkulaense 的核型公式为2n = 16 = 2m (2SAT) + 6sm + 8st; 单花翠雀花 D.candelabrum var. monanthum 的核型公式为2n = 16 = 2m + 6sm + 8st; 展毛翠雀花D. kamaoensevar. glabrescens 的核型公式为2n = 16 = 2m + 6sm + 8st; 前5 种植物的染色体数目与核型为首次报道。  相似文献   

9.
对我国辽宁地区毛莨科(Ranunculaceae)乌头属(Aconitum)6个种的染色体的数目和形态进行了研究,并进行了核型分析。其染色体基数为X=8,核型公式为:两色乌头:2n=2x=2m+10sm+4st;蛇岛乌头为:2n=4x=10m+20sm(SAT)+2st+2B;黄花乌头为:2n=4x=4m+12sm(SAT)+8st+1B;北乌头三倍体为:2n=3x=2M+4m+18sm;北乌头4倍体为2n=4x=4m+28sm。同时,对乌头属下某些种的分类学问题进行了探讨  相似文献   

10.
金伟  王恩波 《植物研究》1998,18(2):162-172
对我国辽宁地区毛莨科乌头属6个种的染色体的数目和形态进行了研究,并进行了核型分析。其染色体基数为X=8,核型公式为:两色乌头:2n=2x=2m+10sm+4st;蛇岛乌头为:2n=4x=10m+20sm(SAT)+2st+2B;黄花乌头为:2n=4x=4m+12sm(SAT)+8st+1B;北乌头三倍体为:2n=3x=2M+4m+18sm;北乌头4倍体为2n=4x=4m+28sm。同时,对乌头属下  相似文献   

11.
不同海拔青海云杉与祁连圆柏叶片抗氧化系统   总被引:5,自引:0,他引:5       下载免费PDF全文
 以祁连山寺大隆林区连续海拔梯度(2 665~3 365 m)上青海云杉(Picea crassifolia)和祁连圆柏(Sabina przewalskii)为材料, 测定叶片中抗氧化保护系统的变化,探讨常绿木本植物抗氧化系统对高山极端环境的适应机制。结果显示, 祁连圆柏和青海云杉叶片中丙二醛(MDA)含量均与海拔高度呈正相关, 相同海拔上青海云杉MDA含量极显著高于祁连圆柏(p<0.01)。随海拔升高, 两树种抗氧化保护酶超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)、谷胱甘肽还原酶(GR)活性和非酶促抗氧化剂脯氨酸(Pro)、抗坏血酸(AsA)、还原性谷胱甘肽(GSH)含量均呈明显增加趋势。青海云杉叶片的AsA水平高于祁连圆柏, 但对海拔变化的敏感性较低; 祁连圆柏的GSH、Pro水平及其对海拔变化的敏感性均高于青海云杉。结果表明, 研究区青海云杉所受过氧化伤害较祁连圆柏更严重, 但两树种清除O2–·的能力相当而主要负责分解H2O2的酶种有所不同: 祁连圆柏中为POD, 青海云杉中则为CAT、APX和GR, AsA-GSH循环系统在青海云杉活性氧清除中的作用强于在祁连圆柏中, 祁连圆柏的活性氧清除物质可能以Pro为主。  相似文献   

12.
Fumonisins, a group of toxic metabolites produced by the genus Fusarium, are known to be consumed by farm animals and are the causative agent or a suspected contributing factor in farm animal diseases. Pigs are particularly susceptible to fumonisins. Reproductive inefficiency is recognized as the most costly limiting constraint to efficient animal production. To account for potential reproductive effects of fumonisin in boars, dietary fumonisin B1 (FB1) was fed to 24 male Large White weanling pigs, 8 to 9 weeks of age. The animals were randomly assigned to four diets containing 5.0, 10.0, 15.0 and 0.2 mg FB1/kg constituting diets 1, 2, 3 and control diet, respectively. After 6 months, semen samples were collected from the pubertal boars and analysed. After the semen collection, all the pubertal boars were killed by decapitation, their reproductive systems dissected and the weights of the testes and epididymides as well as the volumes of the testes recorded. Dietary FB1 did not influence both the relative weights of the testes and epididymides as well as the volumes of the testes. Except for the semen volume and spermatozoa morphological abnormalities, all the semen characteristics studied decreased in a dose-dependent manner and the decrease was statistically significant (P < 0.05). The sperm concentration, total sperm and motile sperm per ejaculate of the animals on diet 3 were 83.3%, 79.1% and 59.6% of the controls, respectively. The dietary FB1 levels influenced the mass activities of the semen, which ranged from very turbulent motion for animals on the control diet to absence of wave motion for those on diet 3. The study revealed that male weanling pigs for breeding should not be exposed to dietary FB1 higher than 5 mg/kg for optimum reproductive performance. The results of this present study suggest that the recommendation of 10 mg/kg by the United States Food and Drug Administration as the maximum level of total dietary fumonisins was above the no-observable-effect level of dietary fumonisin for swine.  相似文献   

13.
To assess the impact of natural landscapes on the population structure of lizards, 10 polymorphic microsatellite DNA markers were developed for the Qinghai toad-headed lizard, Phrynocephalus vlangalii. The number of alleles at these informative loci ranged from four to 28. The novel markers and those previously developed for Phrynocephalus przewalskii were cross-tested among three toad-headed lizard species P. vlangalii, P. przewalskii and P. guttatus. A high cross-utility rate of more than 58% was observed among these three species. These markers are expected to be useful tools for taxonomic considerations as well as population genetic analysis and future conservation management.  相似文献   

14.
Aims When sympatric flowering plant species in a natural community share pollinators, study of plant–plant interactions via interspecific pollen transfer (IPT) is essential for understanding species coexistence. However, little is known about the extent of IPT between interactive species and its causes.Methods To explore how sympatric flowering plants sharing pollinators minimize deleterious effects of IPT, we investigated the pollination ecology of two endemic species, Salvia przewalskii and Delphinium yuanum, in an alpine meadow in the Hengduan Mountains, southwest China. We quantified conspecific and interspecific visits by shared bumblebee pollinators, amounts of pollen placed on different body sites of the pollinators and stigmatic pollen loads on open-pollinated flowers. To examine whether IPT affects female fitness, we measured pollen germination and seed production in the two species in an artificial pollination experiment.Important findings One bumblebee species, Bombus trifasciatus, was found to be the sole effective pollinator for the two coflowering species. Pollination experiments indicated that deposition of heterospecific pollen could significantly decrease seed set in both species. Experiments showed that S. przewalskii pollen could germinate well on stigmas of D. yuanum, inhibiting conspecific pollen germination in D. yuanum. However, seed set was not lower under open pollination than under cross-pollination within species, suggesting that no female fitness loss was caused by IPT. In foraging bouts with pollinator switches, switches from S. przewalskii to D. yuanum were relatively more frequent (8.27%) than the converse (1.72%). However, IPT from S. przewalskii to D. yuanum accounted for only 1.82% of total stigmatic pollen loads while the reverse IPT to S. przewalskii was 8.70%, indicating that more switches of bumblebees to D. yuanum did not result in higher IPT. By contrast, selection for reduced IPT to S. przewalskii would limit pollinator switches from D. yuanum. We found that a bumblebee generally carried pollen grains from both species but the two species differed in the position of pollen placement on the bumblebee's body; S. przewalskii ' s pollen was concentrated on the dorsal thorax while D. yuanum ' s pollen was concentrated ventrally on the head. This differential pollen placement along with pollinator fidelity largely reduced IPT between the two species with a shared pollinator.  相似文献   

15.
The objective of this study was to examine the spatial genetic relationships of the Lake Qinghai scaleless carp Gymnocypris przewalskii within the Lake Qinghai system, determining whether genetic evidence supports the current taxonomy of Gymnocypris przewalskii przewalskii and Gymnocypris przewalskii ganzihonensis and whether Gymnocypris przewalskii przewalskii are returning to their natal rivers to spawn. Comparison of mitochondrial (control region) variation (42 haplotypes in 203 fish) of G. przewalskii with the postulated ancestral species found in the Yellow River, Gymnocypris eckloni (10 haplotypes in 23 fish), indicated no haplotype sharing, but incomplete lineage sorting. Consistent with the sub-species status, an AMOVA indicated that the Ganzi River population was significantly different from all other river populations (F(ST) = 0·1671, P < 0·001). No genetic structure was found among the other rivers in the Lake Qinghai catchment. An AMOVA of amplified fragment length polymorphism (AFLP) loci, however, revealed significant genetic differences between most spawning populations (F(ST) = 0·0721, P < 0·001). Both mitochondrial and AFLP data found significant differences among G. p. przewalskii, G. p. ganzihonensis and G. eckloni (F(ST) values of 0·1959 and 0·1431, respectively, P < 0·001). Consistent with the incomplete lineage sorting, Structure analysis of AFLP loci showed evidence of five clusters. One cluster is shared among all sample locations, one is unique to G. p. ganzihonensis and G. eckloni, and the others are mostly found in G. p. przewalskii. Genetic evidence therefore supports the current taxonomy, including the sub-species status of G. p. ganzihonensis, and is consistent with natal homing of most Lake Qinghai populations. These findings have significant implications for the conservation and management of this unique and threatened species. The evidence suggests that G. p. przewalskii should be treated as a single population for conservation purposes. Exchangeability of the populations, however, should not be used to promote homogenization of fish spawning in the different rivers. As some degree of genetic divergence was detected in this study, it is recommended that the spawning groups be treated as separate management units.  相似文献   

16.
甘肃贝母性状变异式样的分析及分类处理   总被引:3,自引:1,他引:2  
通过实地调查和查阅标本,对甘肃贝母(Fritillaria przewalskii Maxim.)17个居群(包括2个暗紫贝母居群)性状的变异式样及变异规律进行了统计分析和研究。结果表明,各居群在性状上变异显著,并呈现连续变化的规律,其变化与地理分布和生境密切相关。本研究还对甘肃贝母分类群的分类地位予以讨论,认为陇南贝母(F.gansuensis)、无斑贝母(F.przewalskii form.emacula)、异色贝母(F.przewalskii var.discolor)及漳县贝母(F.przewalskii cv.Zhangxian)应归入甘肃贝母,格纹贝母(F.przewalskii var.tessellata)仍作为甘肃贝母的一个新变种。  相似文献   

17.
通过野外定点观察,运用花粉—胚珠比、联苯胺—过氧化氢法、杂交指数、人工授粉和套袋试验等方法,对黄花角蒿(Incarvillea sinensis var. przewalskii)的开花动态及繁育系统进行了研究。结果表明:黄花角蒿种群花期一般为6~9月,单花花期一般为2~3 d,花雌雄异熟,雄蕊先熟,雌雄蕊异位。单花花期依其形态和散粉特征可分为散粉初期、散粉盛期、散粉末期、凋谢期4个时期。黄花角蒿花粉—胚珠比为331.3,杂交指数等于5,结合人工授粉和套袋实验结果可以确定该物种的繁育系统为异交,部分自交亲和,需要传粉者。套袋实验及实地观察显示黄花角蒿为虫媒传粉。  相似文献   

18.
泽兰实蝇内生殖器官的结构及其发育状况   总被引:1,自引:0,他引:1       下载免费PDF全文
【背景】泽兰实蝇属双翅目实蝇科,是杂草紫茎泽兰的重要专性天敌。该蝇幼虫可蛀入紫茎泽兰内部形成虫瘿,有效控制紫茎泽兰的扩散,许多国家都利用泽兰实蝇控制紫茎泽兰的危害。【方法】通过光学显微法观察了泽兰实蝇成虫内生殖器官的结构及其发育动态。【结果】雌性泽兰实蝇的内生殖系统主要由卵巢、输卵管、受精囊、雌性附腺等器官组成,雄性生殖系统由精巢、输精管、雄性附腺、射精管组成。在成虫发育过程中,雌虫卵巢的长度在第4日龄时达最大值,宽度在1日龄时达最大值,与其他日龄相比有显著差异,雌性附腺及受精囊的大小在各日龄间无显著差异;雄虫精巢长度在4日龄时达到最大,宽度在2日龄时达最大,且不同日龄间也有显著差异,而雄性附腺的大小在不同龄期间无显著差异。【结论与意义】本文阐明了泽兰实蝇的内生殖系统结构与发育状况,这有助于为提高泽兰实蝇人工繁殖效率及生物防治效果奠定理论基础。  相似文献   

19.
6个地区青海湖裸鲤肌肉营养成分分析   总被引:4,自引:1,他引:3  
采用常规生化分析方法,测定青海湖6个不同地区的青海湖裸鲤(Gymnocypris przew alskii)肌肉主要营养成分,对其营养价值进行评价。结果表明,淡水青海湖裸鲤肌肉中脂肪含量显著大于(P<0.05)其他5个地区,蛋白含量显著大于(P<0.05)黑马河青海湖裸鲤肌肉的蛋白含量,6个地区青海湖裸鲤肌肉营养成分存在一定的地区差异。总体上,青海湖裸鲤肌肉(鲜样)中粗蛋白含量为17.26%~18.87%;粗脂肪含量为1.51%~3.37%;灰分含量为1.42%~1.61%;18种氨基酸总量15.48%~17.16%,其中除色氨酸外7种人体必需氨基酸总量6.38%~7.05%,4种鲜味氨基酸总量5.82%~6.49%。青海湖裸鲤肌肉中蛋白质含量较高,氨基酸种类齐全,必需氨基酸与鲜味氨基酸含量较高,尤其是淡水青海湖裸鲤品质更佳,淡水的生态环境可能更适合青海湖裸鲤的生长。  相似文献   

20.
采用呼吸生理和血液生理的方法,探讨了性成熟青海湖裸鲤(Gymnocypris przewalskii)对盐度、碳酸盐碱度的适应性以及青海湖裸鲤在盐碱胁迫下的渗透调节和离子调节规律。将裸鲤从淡水突变到盐水(盐度14.01±0.01)、碱水(碳酸盐碱度33.03±0.01mmol·L-1)和青海湖水(盐度12.12±0.02、碳酸盐碱度29.07±0.09mmol·L-1)中,测定了在不同水质胁迫下裸鲤耗氧率、血浆渗透压和离子浓度的变化。结果表明:与淡水对照组比较,呼吸耗氧率除了盐度组在3h有显著性升高(P<0.05),其他实验组96h内均未出现显著性变化(P>0.05);裸鲤的窒息点为0.14~0.17mg·L-1,各实验组窒息点均没有显著性差异(P>0.05);碱度组血浆的渗透浓度和Na+、Cl-、Ca2+离子浓度在96h内未出现变化(P>0.05),盐度组和青海湖水组在所测时间段有显著的升高(P<0.05),并且随着胁迫时间的延长,在72h达到峰值。各实验组血浆K+浓度变化没有血浆Na+、Cl-明显,K+浓度有增高的趋势,且都在72h达到了峰值。青海湖裸鲤具有较强的盐碱耐受性,能通过渗透调节和离子调控适应高盐碱环境,而消耗能量较少。  相似文献   

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