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1.
本研究采用传统的细胞遗传学方法，从牛体外受精后产生的6～8d囊胚中制备染色体，以探讨适合牛胚胎染色体制备的方法。将牛的6～8d回收的囊胚分别在含0．1μg／mL、lμg／mL和10μg／mL秋水仙酰胺(Colcemid)的TCMl99液中继续培养4h或6h，以抑制细胞分裂停留在中期。经处理后的囊胚移入10g／L柠檬酸钠的低渗液中，室温下处理15～20min.将低渗后的单个胚胎转移至载玻片上，经固定液I和固定液Ⅱ固定后，用体积分数为25％的Giemsa溶液染色10min，蒸馏水冲洗脱色，于室温自然干燥。显微镜下计算胚胎细胞数和有丝分裂指数以及观察染色体的伸展情况。结果显示，1μg／mL秋水仙酰胺处理6h后染色体制备的结果较为理想。 相似文献
2.
以采自静宁的葫芦巴为材料,研究了1 mol/L的盐酸在60 ℃下的不同解离时间对根尖染色体制片的影响,并确定染色体数目和进行核型分析。结果表明,静宁葫芦巴根尖最佳解离时间为2.0～2.5 min。染色体数为16,核型公式为2n＝2x=16=8m+8sm(2SAT),臂比值变化在1.07～2.88,平均臂比为1.926,随体在第6对染色体短臂上,核型类别为2A。 相似文献
3.
黑麦品种间耐铝差异性机制研究 总被引：1，自引：0，他引：1
采用室内模拟方法,研究了铝诱导黑麦根系分泌有机酸、根尖磷对铝的固定作用。结果表明,在铝胁迫下冬牧品种（Win）相对根伸长率高于King品种。在铝胁迫下,经磷预处理的根尖铝和磷含量增加,且以Win品种根尖中的Al、P含量较高,说明根尖磷对铝的固定是黑麦耐铝机制之一。另一方面,在铝胁迫下,两品种根系均分泌柠檬酸和苹果酸,且Win的分泌速率较高。有机酸的分泌随着铝处理浓度（10、30、50 mol/L）和时间（0.5、3、6、9、12 h）的增加而增加,但在低温（4C）下柠檬酸分泌量显著减少。Al处理0.5 h后苹果酸已明显分泌,而柠檬酸的分泌在铝处理6 h后才明显增加。在铝处理前,进行缺磷预处理（3 d）不能增加有机酸的分泌,10 mol/L的La3+、Cu2+、Ni3+也不能诱导根系分泌有机酸。说明铝诱导根系专一性分泌有机酸也是黑麦品种间耐铝性差异的机制。 相似文献
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镉胁迫对水稻幼苗生长和根尖细胞分裂的影响 总被引：9，自引：0，他引：9
研究了镉(Cd)对水稻幼苗生长、根尖细胞有丝分裂及染色体畸变的影响。结果表明,随着Cd浓度增加和处理时间延长,水稻幼苗根的生长及根尖细胞有丝分裂指数明显降低。Cd使有丝分裂中期细胞所占比例相对增加,前期、后期、末期细胞相对减少。Cd能诱导染色体产生多种类型的畸变,染色体畸变率随着Cd处理浓度的增加和处理时间的延长而升高,呈现明显的剂量-效应和时间-效应关系。1～10μmol L-1Cd胁迫24 h后,水稻根尖畸变主要有C-有丝分裂、染色体桥,占总畸变率的32.64%～78.29%;25～200μmol L-1Cd胁迫24～72 h后,水稻根尖细胞中染色体粘连、断片和微核占较大比例,占总畸变率的76.44%～93.96%。研究表明,Cd对水稻根尖分生细胞有丝分裂具有阻滞作用,并诱发染色体畸变率的显著升高。 相似文献
7.
本研究拟通过原生体培养和不对称细胞杂交实现白脉根与苜蓿种间基因重组,为改良苜蓿饲用品质提供新的技术手段,用酶解法分离清水紫花苜蓿(Medicago sativa L.cv.‘Qingshui’)及里奥百脉根(Lotus corniculatus L.cv.‘Leon’)愈伤组织来源的原生质体,研究了酶解时间、酶液组合、甘露醇浓度、预处理条件、继代时间及培养方法等对原生质体分离和培养效果的影响。采用改良的PEG-高Ca2+-高p H法进行了不对称体细胞杂交,通过荧光染色鉴别异核体并测定融合率。结果表明,采用继代培养第8~12天的苜蓿和百脉根愈伤组织,0.55 mol·L-1CPW溶液中预处理1h或预暗培养24 h,甘露醇浓度为0.55~0.6 mol·L-1时,清水紫花苜蓿在2%纤维素酶+0.5%果胶酶+0.3%崩溃酶的酶液中酶解10 h,里奥百脉根在2%纤维素酶+0.5%果胶酶+0.3%半纤维素酶的酶液中酶解12 h,经2~3个月的固液+固体培养模式可分别获得较好的原生质体分离效果及愈伤组织再生植株。清水紫花苜蓿原生质体经3 mmol·L-1IOA处理10 min,里奥百脉根经50μg·m L-1R-6G处理10 min后融合,PEG(6000)最适浓度为35%,异源融合率为3.1%,最终获得了苜蓿与百脉根的杂种愈伤组织,为进一步培育抗臌胀病型苜蓿种质提供了新的材料。 相似文献
8.
不同预处理对长寿沙田柚根尖染色体制片的影响 总被引：1，自引：0，他引：1
本研究采用0.1%秋水仙素、对二氯苯饱和水溶液、对二氯苯-α-溴萘混合液这3种常用于植物染色体预处理的药剂,研究了不同处理方式对长寿沙田柚根尖细胞染色体制片效果的影响。结果表明:利用对二氯苯-α-溴萘混合液预处理根尖12h效果最好,中期分裂指数高,染色体分散、清晰。 相似文献
9.
本研究采用0.1％秋水仙素、对二氯苯饱和水溶液、对二氯苯-α-溴萘混合液这3种常用于植物染色体预处理的药剂,研究了不同处理方式对长寿沙田柚根尖细胞染色体制片效果的影响.结果表明:利用对二氯苯-α-溴萘混合液预处理根尖12h效果最好,中期分裂指数高,染色体分散、清晰. 相似文献
10.
铝诱导黑麦的根尖分泌有机酸 总被引：8，自引：0，他引：8
黎晓峰 《广西农业生物科学》2002,21(2):78-82
虽然较多的研究已发现黑麦对铝毒害的忍耐能力较强，但是有关黑麦对铝毒害的抵御机理的报告很少。为了阐明黑麦（品种：King)对铝毒害的抵御机理，本研究探讨了黑麦的根系有机酸分泌的特性及其作用，铝能够诱导黑麦的根系分泌柠檬酸和苹果酸。柠檬酸主要从距顶端0－5mm的根尖分泌。有机酸的分泌量随着处理的铝浓度(0,50,100,300μmol/L AlCl3）和处理的时间（0．5，1，3，5h）的增加而增加。0，50，100，300μmol/L的AlCl3处理根尖3h后，从根尖分泌的柠檬酸和残留在根尖中的柠檬酸之和随着处理的铝浓度的增加而增加，而各处理间的苹果酸总量无显著差异。50μmol/L的柠檬酸或者400μmol/L的苹果酸能够消除50μmol/L 的AlCl3铝对小麦（Scout 66)根尖表面细胞的伤害。这些结果表明，铝促进柠檬酸的合成和柠檬酸、苹果酸从根尖的分泌是黑麦抵抗铝毒害的机理。 相似文献
11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响 总被引：2，自引：2，他引：0
【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。 相似文献
12.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions. 相似文献
13.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing. 相似文献
14.
Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization
and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition
with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the
decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots
with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass,
soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration,
N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially
(<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation
in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils,
indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but
the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation
for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community
performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea. 相似文献
15.
《中国生态农业学报》2014,(6)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
16.
《中国生态农业学报》2014,(7)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
17.
《中国生态农业学报》2014,(8)
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology, 相似文献
18.
I.L. Boyd 《Biological conservation》2010,143(7):1664-1674
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options. 相似文献
19.
Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage 总被引：1，自引：0，他引：1
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate. 相似文献
20.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils. 相似文献