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51.
M. E. FERGUSON B. V. FORD-LLOYD L. D. ROBERTSON N. MAXTED & H. J. NEWBURY 《Molecular ecology》1998,7(12):1743-1755
Plant genetic resource conservation strategies, informed by an understanding of the geographical distribution of genetic variation within species, are likely to result in a wider representation of conserved diversity in ex situ gene banks and in situ genetic reserves. The main objective of this study was to map the geographical distribution of genetic variation, as revealed by randomly amplified polymorphic DNA (RAPDs), in four wild relatives of the cultivated lentil, namely Lens culinaris ssp. orientalis, L. odemensis, L. ervoides and L. nigricans . Areas of high diversity and unique diversity were located for each taxon, and regions where further germplasm collection was most likely to yield novel genetic variation were identified. There were centres of diversity for L. culinaris ssp. orientalis in southeast Turkey and northwest Syria, and in south Syria and Jordan. A centre of diversity was found to exist in Sweida province, south Syria, for L. odemensis , and for L. ervoides along the coastal border region between Syria and Turkey stretching down along the Syrian coast. There was a centre of diversity for L. nigricans in west Turkey. Analytical techniques previously used at the species level were found to be useful at the genotypic level to objectively target areas for future collection missions, to increase diversity in ex situ collections and to target areas for in situ conservation. 相似文献
52.
以萌发初期大豆弯曲的子叶节为靶点,利用草甘膦(Roundup)点施鉴定法,分析了221份大豆微核心种质的草甘膦耐受性及其与抗草甘膦转CP4-EPSPS基因大豆AG5601的差异,结果表明,草甘膦对不同大豆种质的抑制程度与点施的草甘膦浓度呈正相关,Roundup稀释浓度为1/1000、1/10000时,草甘膦对大豆生长几乎无影响;Roundup稀释浓度为1/10时,草甘膦显著抑制大豆生长,导致植株死亡;Roundup稀释浓度为1/100时,不同大豆种质对草甘膦耐受性差异显著,并鉴定出对草甘膦具有较好耐受性的种质10份。虽然大豆微核心种质对草甘膦的耐受程度远远低于AG5601,但不同大豆种质对草甘膦耐受性存在显著差异,这为利用转基因和杂交转育技术培育抗草甘膦转基因大豆的受体或轮回亲本的选择提供了理论依据。 相似文献
53.
We report here that, during periodical surveys of insects inhabiting diverse habitats for the collection of entomopathogenic
fungi; a large number of isolates were recovered belonging to seven species, from various regions of Madhya Pradesh and Chhattisgarh
forest areas and agricultural fields. The most common entomopathogenic fungi such as Beauveria bassiana, Nomuraea rileyi, Paecilomyces farinosus and Paecilomyces fumosoroseus were found to infect various insect hosts species naturally viz. Hyblaea puera, Eutectona machaeralis, Diachrysia orichalcea, Spodoptera litura, and few new insect hosts of these fungal pathogens among Indian insect population were collected for the first time from
Central India, such as beetles of Agrilus species, hairy caterpillars of Lymantria species. The isolation, identification, maintenance and pathogenicity assay of these isolates was performed prior to deposition
in culture collection center. 相似文献
54.
目的:了解举证责任倒置实施以来,该政策对医生的影响及实施中存在的问题。方法:应用自制问卷,对青岛、西安两地9家三甲综合性医院共256名医生进行问卷调查,运用spss16.0进行统计分析。结果:举证责任倒置一方面给医生的医疗行为带来了积极影响,另一方面也给医生带来了较大的心理压力,尤其是发生过纠纷、被起诉的医生,对其以后的行为产生了消极影响。结论:医院除应加强对医生医疗技术、法律知识培训外,还应成立专门的机构来缓解医生的心理压力,解除其心理问题。 相似文献
55.
Open‐tube volatile traps have largely been shunned in favor of solid adsorbent containing traps for the collection of volatile pheromones and attractants. Solid adsorbents require large solvent rinses and glass capillaries can be difficult to maneuver for the collection of volatiles from small or hard‐to‐reach odor sources. A gas chromatograph (GC) column (DB‐1), an open‐tube glass capillary, and a SuperQ®‐containing capillary were compared for their collection efficiencies from rubber septa and live calling insects. All three traps captured similar ratios of test compounds from septa at airflows >10 ml per min. Eluting analytes from a packed adsorbent, SuperQ, required at least 30× more solvent than was required to collect all the pheromone from the open‐tube glass capillaries, and the GC column enjoyed an additional three‐fold reduced solvent volume compared to the glass capillary. Thus, analytes could be eluted from the GC‐column trap and directly analyzed on GC without solvent evaporation. We placed glass wool ‘plugs’ in both GC columns and glass capillaries and found no volatiles in these plugs, indicating that breakthrough did not occur during 1‐h collections at 25 ml per min. We demonstrate here that at ambient laboratory temperatures, a DB‐1 GC column effectively collects Oriental fruit moth sex pheromone volatiles from a rubber septum and live pheromone‐releasing moths. Release ratios of pheromone from rubber septa are consistent with earlier reports from static air systems, whereas the release ratio of the (Z)‐8‐dodecenyl alcohol (Z8‐12:OH) from female Grapholita molesta Busck (Lepidoptera: Tortricidae) differed from published results and is likely due to different collection methods or moth‐strain origin. 相似文献
56.
目的介绍小鼠颌下静脉丛采血方法。方法选用2月龄昆明小鼠,固定小鼠后,将采血注射针头刺入颌下静脉丛血管取血。结果单人操作约1 min内可完成小鼠颌下静脉丛采血,采血量达到0.3-0.5 mL。结论此方法无需麻醉、创伤小、采血量大并可重复采血,是一种简便、安全、快速、采血量多的采血方法。 相似文献
57.
为提高种质资源在育种中的利用效率,建立了我国绿豆(Vigna radiata)应用型核心样本。该样本既包括了资源库中具特异性状的种质和曾经在生产上大面积种植的品种,也包括了在育种中使用频繁的亲本及苗头品系等。农艺性状变异分析表明,该核心样本具有丰富的表型变异,是绿豆种质资源的代表性样本。聚类分析可将核心样本分为4大类,但类别内种质与其地理来源相关不明显。不同来源表型数据的分析发现,不同性状间的一致性存在差异。但产量相关性状的表现均与当前育种目标相接近,说明该核心样本具有较高的实用性。 相似文献
58.
59.
60.
目的研究不同时间间隔经眼眶静脉丛多次采血后,对雄性Wistar大鼠重要脏器系数的影响。方法实验组分别间隔3 d、7 d、10 d,经眼眶静脉丛采血,每次采血1 mL,共采3次。对照组于实验组最后一次采血时采血一次,采血1 mL。每次采血前称量体重,于最后一次采血后将大鼠处死,取心脏、肝脏、肾脏、脾脏、胸腺,称量脏器重量,计算脏器系数。结果间隔3 d多次采血,大鼠的肝、肾系数差异具有显著性(P〈0.05),间隔7 d、10 d多次采血,大鼠的各脏器系数差异无显著性。结论间隔3 d多次采血对大鼠的肝、肾系数有影响,间隔7 d、10 d多次采血对各脏器系数均无影响。 相似文献