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根据已报道的小麦Pinb基因的保守序列,设计合成了1对特异性引物,对二角山羊草(Aegilops bicornis,SS)的基因组DNA进行Pinb基因扩增、克隆、序列分析,发现了1个新型Pinb等位基因,基因长360bp,编码119个氨基酸残基,对应于麦类作物PinB成熟蛋白结构区域,具有其特有的WPTKWWK色氨酸结构域和10个半胱氨酸所形成的5个二硫键结构。与软粒小麦cv.Capitole的Pinb-D1a相比较,其核苷酸和氨基酸同源性分别为93.1%和91.6%。RT-PCR证实了Pinb基因在籽粒胚乳中的表达。研究结果表明,二角山羊草中包含着与小麦差异较大的籽粒硬度控制基因,为栽培小麦品质改良提供了丰富的遗传资源。  相似文献   

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European Journal of Wildlife Research - The food habits and behavior of medium and large-sized mammals that visited natural salt-licks in a tropical rainforest of Belum-Temengor Forest Complex,...  相似文献   

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We analysed genetic variation in mitochondrial DNA (mtDNA) control region in the Diceros bicornis minor and D. b. michaelianimals at the Western Plains Zoo, which form part of an international ex-situ breeding program. Six of the nine D. b. minor animals were wild-caught from Zimbabwe during the 1990s, and our study revealed five distinct mtDNA haplotypes, and a haplotype diversity of 0.86 in the colony. Phylogenetic relationships between mtDNA haplotypes analyzed using the neighbor joining method reveal that for the small sample available, D. b. minor and D. b. michaeli are reciprocally monophyletic and represent separate ancestral lineages. Nucleotide divergence between the black and and white rhinoceros(Ceratotherium simum) was 14.0%, and nucleotide divergencebetween the D. b. minor and the D. b. michaeli subspecies was 2.6%. This suggests a divergence time for the two blackrhinoceros subspecies of between 0.93 MY and 1.3 MY.  相似文献   

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Black rhino numbers have decreased greatly since the early 1970s, primarily as a result of poaching. A recent strategy to protect rhinos in Kenya has been to establish fenced sanctuaries. This has increased the rhino population and that of other species, but problems have emerged because of limited dispersal and rising animal densities. Unfortunately, how rhino utilize habitat, especially areas called bedding sites, is not well understood. These areas provide shade and may be a critical component of rhino habitat. We measured habitat variables at bedding sites located in bedding plots and compared them with control plots at Sweetwaters Reserve, Kenya. Euclea divinorum was the most common tree in the bedding site comprising 64.3% of the vegetation. Elephant dung was significantly more likely to be found in bedding plots than in control plots which suggests that elephants and rhinos use overlapping habitats. Elephants may be causing damage to the tree species that are important for bedding sites. Resource competition between large herbivores in small reserves is likely to negatively affect the tree species. Black rhino habitat, particularly bedding sites, may be at risk and rhino numbers may decrease.  相似文献   

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Stoops MA  O'Brien JK  Roth TL 《Theriogenology》2011,76(7):1258-1265
Mortality rates are high among captive African black rhinoceroses (Diceros bicornis), due to increased susceptibility to disease. The ability to rescue genetic material from individuals that die unexpectedly represents a practical approach to assist ex situ conservation efforts. The objectives of the present study were to attempt postmortem oocyte recovery from ovaries of African black rhinoceroses (N = 6) and to test the efficacy of equine protocols for rhinoceros oocyte IVM and IVF using cryopreserved rhinoceros sperm. The interval from ovary removal to oocyte recovery was 25.3 ± 13.9 h (mean ± SD). Ovaries were transported at 4 °C or 22 °C and effects of temperature on postmortem oocyte competence was evaluated. Numbers of oocytes collected per female averaged 15.8 ± 6.9. In total, 95 oocytes were recovered. Of these, 85 were inseminated using homologous sperm and 10 were inseminated using heterologous sperm. Overall, substantial numbers of viable oocytes were retrieved from African black rhinoceros ovaries 1 to 2 days postmortem from ovaries stored at ambient temperature. A proportion of these oocytes matured and underwent penetration and fertilization by heterologous or homologous frozen-thawed rhinoceros sperm. The reproductive competence of postmortem oocytes was further demonstrated by development of a single two-cell embryo. Despite the need for further refinements, gamete rescue in the rhinoceros has promise for producing rhinoceros embryos, as well as testing sperm functions in vitro.  相似文献   

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研究脱落酸引发及其与植物生长调节剂的复合处理对夜香紫罗兰(Matthiola bicornis)种子萌发的效应.结果表明,将夜香紫罗兰种子于20℃下在2.5×10-5 mol/L脱落酸(ABA)溶液中引发7 d,能显著缩短种子平均萌发时间,增加种子萌发指数.在ABA溶液中加入吲哚乙酸(NAA)未能进一步改善夜香紫罗兰种子萌发,但其他复合处理均显著提高正常幼苗百分率.ABA和细胞分裂素(KT)及NAA复合处理进一步增加种子萌发指数,不仅比单独用ABA引发的效果好,而且也比用聚乙二醇(PEG)引发的效果好.ABA引发和PEG引发的夜香紫罗兰种子相对吸水量显著不同.对ABA引发机理和应用潜力进行了讨论.  相似文献   

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The kidney of Diceros bicornis has about 60 lobes, all appearing peripherally. These are separated by interlobar septa, except for small septal defects through which tubules pass. Renal capsule and interlobar septa are fibromuscular and contain small blood vessels. The kidney is about 65% cortex. It contains about 12.5 x 10(6) glomeruli, which form about 7% of the cortical mass and 4.6% of the renal mass. Diameter of a glomerular capsule is about 244 microns, there being no difference in size across the cortex in these adults. The ureter bifurcates into a cephalic and a caudal, fibromuscular, urothelial-lined conduit, into which open about 23 urothelial-lined infundibula. The common large collecting duct, or tubus maximus, of every lobe opens at the apex of its infundibulum. Two tubi may join into one infundibulum. The tubi and their terminal collecting ducts (of Bellini) are part of the inner medulla. Musculature of conduits and infundibula is largely longitudinal. The calyx may be represented by a circular muscle bundle near the apex of every infundibulum. The large intralobar veins are partly adherent to their infundibulum and calyx and receive arcuate veins via valved orifices. Most branches of the renal artery enter via the interlobar septa. Within a septum they branch again and also supply numerous perforators, which thence enter the cortex. Remaining branches of the renal artery enter cortex directly from without. A fibromuscular scaffolding lies deep to arcuate veins where they contact medulla. Where these veins contact cortical tubules; however, their walls become merely endothelium, like the walls of the interlobular veins.  相似文献   

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The red mason bee Osmia bicornis L. (Hymenoptera: Megachilidae) belongs to a group of insects that undergo an obligatory diapause in the imago stage. Red mason bees (O. bicornis) consume oxygen during overwintering diapause, and reactive oxygen species can be produced despite substantial inhibition of metabolism. These are first studies to investigate the antioxidant system in diapausing red mason bees and to compare the antioxidant systems of overwintering and active imagines. The present study analyzes total antioxidant status, glutathione and ascorbic acid levels, and the activity of superoxide dismutase, catalase and peroxidase in overwintering (October to March) and active (April) female and male O. bicornis. Diapause phases (prediapause, diapause and post‐diapause) cannot be distinguished based on the parameters of the antioxidant system of the bees. During overwintering, a significant decrease is noted only in ascorbic acid content. The remaining antioxidants remain fairly stable, which indicates the absence of oxidative stress in diapausing specimens. The analyzed parameters distinguish diapausing bees from active insects. Excluding total antioxidant status, the evaluated parameters are significantly higher in active individuals than in overwintering specimens. Sex‐related differences are found only for catalase, the level of which is consistently higher in males than in females.  相似文献   

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两类二角山羊草细胞质小麦雄性不育系的细胞学研究   总被引:3,自引:2,他引:1  
对具有二角山羊草(Aegilops bicornis)细胞质的同质异核1BL/1RS型小麦雄性不育系ms(Ae.bicornis)-5-1和非1BL/1RS不育系ms(Ae.bicornis)一V9125进行了花药发育细胞学分析。幼穗染色体制片显示,1BL/1RS不育系ms(Ae.bicornis)-5—1减数分裂正常,非1BL/1RS不育系ms(Ae.bicornis)-V9125减数分裂期染色体排列不整齐,出现不正常的四分体和含微核的小孢子。花药发育的细胞学观察表明,1BL/1RS不育系ms(Ae.bicornis)-5—1表现为染败,花药各壁层的发育是正常的;BC3代的非1BL/1RS不育系ms(Ae.bicornis)-V9125表现为园败,且发生了药室合并现象,从细胞学角度证明了二角型小麦不育系存在两个核质互作不育系统。  相似文献   

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The presence of eyelashes on the lower eyelid of an adult Diceros bicornis (L.) was observed and recorded by photography.  相似文献   

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The mean plasma level of alpha-tocopherol (vitamin E) measured in 31 free-ranging black rhinoceros (Diceros bicornis) was significantly higher (P less than 0.001) than that in 11 captive animals (means +/- SE = 0.77 +/- 0.05 and 0.18 +/- 0.03 micrograms/ml, respectively). Vitamin E status may influence the health of captive black rhinoceros; in particular, it may be linked to hemolytic anemia commonly observed in these animals in captivity.  相似文献   

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Despite an on-going struggle to conserve the endangered black rhinoceros (Diceros bicornis) since the 1980s, huge capital investment and several genetic surveys, the level of genetic structure and connectivity among populations in southern Africa is not well understood. Here, we undertake a major population genetic study of black rhinoceros in the Zimbabwe Lowveld, an area inhabited by over half of that country’s original Zambezi descendants plus one large population sourced from the relict KwaZulu stock of South Africa. Using nuclear microsatellite and mitochondrial DNA data, we found much higher levels of genetic diversity in the indigenous Zimbabwean populations, where observed multilocus heterozygosity was 0.54 versus 0.40 in KwaZulu, and maternal haplotype diversity was 0.77 versus 0.03. We show, for the first time, that both gene pools can be differentiated from each other on the basis of nuclear markers. This, along with the discovery of recent gene flow between all Lowveld populations, suggests that Zimbabwean and South African gene pools were prehistorically connected.  相似文献   

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The first Black rhino was kept in Berlin Zoo in 1870. After second world war the keeping of Diceros bicornis started in 1954. Between 1981 and 2006 16 births occurred in Berlin Zoo, of which 14 calfs were raised.  相似文献   

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