共查询到19条相似文献，搜索用时 359 毫秒
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对高粱属(Sorghum)4种植物假高粱(S.halepense)、黑高粱(S.almlzm)、高粱(S.bicolor)和苏丹草(S.sudanense)的染色体数目和核型进行了研究.结果表明,假高粱的核型公式为2n=4x=40=28m+12sm,属2B型,核型不对称系数为59.92%;黑高粱的核型公式为2n=4x=40=32m+8 8m,属1B型,核型不对称系数为58.68%.苏丹草的核型公式为2n=2x=20=18m+2sm,属1A型,核型不对称系数为55.56%;高粱的核型公式为2n=2x=20=16m+4sm,属2A型,核型不对称系数为57.95%.与高粱和苏丹草两种作物相比,具有入侵性的假高粱和黑高粱为多倍体、核型不对称性程度更高. 相似文献
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本文采用秋水仙素—低渗空气干燥法从骨髓中期制备了分布于新疆准噶尔盆地南缘的四种啮齿类核型,其结果为:子午沙鼠zn=50,N.F=78,K.F=26M+22T+XY(M,M)。大沙鼠2n=44,N.F=72,K.F=24M+2SM+2ST+12T+XY(M,M)。小五趾跳鼠2n=48,N.F=83,K.F=16M+18SM+2ST+10T+(ST,ST)。小家鼠2n=40,N.F=40,K.F=38T+XY(T,T)。这几种啮齿类的核型曾有过报道,它们与本文报道种类,除二倍体数一致外,均见不同差异或显著差异,这种差异表明,物种由于分布的广域性与地理隔离,染色体发生重组,导致亚种分化,从而呈现染色体的多态现象。 相似文献
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棉铃虫核型多角体病毒分子生物学和基因工程研究进展 总被引：1，自引：1，他引：1
棉铃虫核型多角体病毒(HaSNPV)是棉铃虫专一性病原物,隶属于杆状病毒科核型多角体病毒属.对其分子生物学和基因工程的研究主要包括以下几个方面:测定了HaSNPV G4株和C1株基因组核苷酸全序列,并与其它病毒进行了同源性比较;研究了HaSNPV部分基因的结构、转录、表达及其功能.构建了HaSNPV Bac to Bac杆状病毒表达系统;重组病毒杀虫剂的研究为HaSNPV大面积防治棉铃虫展示了广阔的前景.随着棉铃虫核型多角体病毒分子生物学和基因工程研究的不断深入,重组病毒杀虫剂将在棉铃虫综合防治中发挥更为重要的作用. 相似文献
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本试验报道以动植物残体和腐植质为食的蚯蚓(威廉环毛蚓Pheretima guillelmi Mi-chaelsen)和一种蛴螬(白星花金龟幼虫Liocola brevitarsis Lewis),具有明显减少杨雪毒蛾(Stilpnotia candida)核型多角体病毒(ScNPV)在土壤中多角体数量的作用。 相似文献
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采用常规根尖压片法对分布于内蒙古自治区阿拉善荒漠地区的骆驼刺(Alhagi maurorum Medil.var.sparsifolium(Shap.)Yakovl.)染色体数目与核型进行了研究分析。结果表明:骆驼刺染色体数目为16条,二倍体。核型公式为2n=2x=16=12m+4sm,核型不对称系数为58.86%,核型类型属于2B型。 相似文献
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杆状病毒非必需基因的结构与功能 总被引：1，自引：0，他引：1
本文主要以苜蓿丫纹夜蛾核型多角体病毒（ＡｃＭＮＰＶ）为例,概述了迄今展报道的杆状病毒非必需基因的结构与功能,为杆状病毒的基因工程研究提供参考。 相似文献
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桑褐刺蛾(Setora postornata Hampson)属鳞翅目刺蛾科。其幼虫为害栗、柿、核桃、梨、白杨和石榴等多种植物的叶。1982年秋,在泰安市下港公社上港和黄前一带发现桑褐刺蛾幼虫自然患病死亡,野外自然感病率高达70%以上。经分离鉴定是一种核型多角体病毒感染所致。本文着重报道该株病毒的分离和形态观察结果。 相似文献
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AcNPV·Bt·En复配剂对甜菜夜蛾幼虫的毒力测定 总被引：6，自引：0，他引：6
甜菜夜蛾(Spodoptera exigua)是一类严重危害多种蔬菜的农业害虫,苏云金芽孢杆菌(Bt)作为害虫微生物防治的主角之一,已广泛应用于农林害虫的生物防治.Bt杀虫剂在田间防治甜菜夜蛾初孵幼虫中显示出良好的杀虫效果,但仍然显示出单剂的缺陷,如残效期短、对大龄幼虫不敏感.苜蓿银纹夜蛾核型多角体病毒(AcNPV)是一种宿主范围较广的昆虫杆状病毒,能感染30多种鳞翅目昆虫,并对甜菜夜蛾有较好的感染致死力.将Bt与AcNPV混用,可充分利用二者的优势.增效蛋白是由某些病毒基因编码的一类金属蛋白酶,具有酯酶活性.纯化的天然增效蛋白在体外能促进NPV对昆虫离体细胞系的感染,能显著提高NPV对昆虫的感染效果,并可增强苏云金杆菌伴孢晶体对幼虫的毒力.本文首次报道基因工程增效蛋白(En)与AcNPV·Bt科学复配使用对甜菜夜蛾的室内毒力测定结果,目的在于寻求甜菜夜蛾综合治理的新途径. 相似文献
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新疆各类陆栖脊椎动物近 70 0种 ,占中国这一类动物种数的 32 %,其中鸟兽资源尤其丰富 ,计有 42 5种鸟类和 1 5 5种兽类 (哺乳类 ) ,占中国鸟兽种数的 31 %。本文主要以新疆三大山区———阿尔泰山、天山、昆仑 -阿尔金山地区鸟类和哺乳类动物的多样性及区系分布作综合性介绍和分析。根据实地考察和以往文献资料 ,新疆阿尔泰山区记录在 1 2 4种鸟类 ,其中古北界北方型鸟类 5 1种 (占 41 .1 %) ,中亚型鸟类 31种 (占 2 5 .0 %) ,广布种鸟类 2 7种 (占 2 1 .8%) ,其他类型1 5种 (占 1 2 .1 %) ,显出以北方型泰加林鸟类为主的鸟类区系特征 ;分布的 5 0种兽类 ,区系上以古北界北方泰加林为主 ,即北方型兽类占该山区种数的 5 2 %。天山山区记录的鸟类大约2 81种 ,北方型种类占绝对优势 ,即北方型 1 0 6种 (占 37.72 %) ,北方广布型 76种 (占 2 7.0 4 %) ,中亚型 39种 (占 1 3.88%) ,高地型 1 8种 (占 6.41 %) ,广布型 33种 (占 1 1 .74%) ,东北型 9种 (占 3.2 1 %)。兽类分布有 62种 ,北方型兽类区系占优势 ,有 30种 (占 48.40 %) ,广布型 1 2种 (占 1 9.40 %) ,中亚型 1 1种 (占 1 7.70 %) ,特有种 9种 (占 1 4.5 0 %)。昆仑—阿尔金山地区 96种鸟类中 ,中亚类型成份占 2 8.1 %,高地型成分占 2 6%,北方型成? 相似文献
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Ming MA Ying CHEN Kedeerhan BAYAHEN BaoWen HU Fei LI JiaQing WU Xiang GAO Yu MEI 《干旱区科学》2010,2(2):151-155
The Relict Gull(Larus relictus) is recognized as a vulnerable species,with a worldwide population of about 6,000 individuals.Always inhabiting the extreme arid regions of Central Asia,their migratory routes and winter grounds are unclear.This research focused on distribution sites,habitat,behavior,population size and seasonal changes of Relict Gull.Line transects and point counts in every month were used to investigate the gulls around the Ebinur Lake.The result showed Relict Gull was summer visitor to Xinjiang,Western China.Population curve with a single peak was obtained.This gull appeared in early April and was 63 individuals(1% of the global population).The number remained stable from May to July in 2009.The discovery of fledglings indi-cates that Relict Gull may breed here.They left Ebinur Lake in August.Relict Gull in Ebinur Lake should belong to the Central Asian subpopulation,which was the most westerly record in China. 相似文献
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First report of Eulachnus tuberculostemmatus (Theobald, 1915) on Pinus nigra subsp. mauretanica stands in Algeria 
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下载免费PDF全文 H. Hedjam F. Marniche S.‐E. Doumandji M. Contarini B. Paparatti S. Speranza F. Krouchi A. Derridj 《EPPO Bulletin》2017,47(1):111-114
Pinus nigra (black pine) is a Mediterranean taxonomic complex (including different subspecies), with a discontinuous distribution. The southernmost part of its range is in North Africa, in Morocco and Algeria, where it is present as P. nigra subsp. mauretanica. Currently, an extremely limited number of trees of this subspecies still persist within its natural range, giving this taxon an outstanding ecological importance. These residual stands are threatened by many biotic and abiotic factors, putting at risk the survival of this subspecies in its natural habitat. This paper reports for the first time the presence of Eulachnus tuberculostemmatus (Hemiptera: Aphididae: Lachninae) in Algeria, and its infestation on P. nigra subsp. mauretanica. This insect was detected in three sites of the Djurdjura National Park in May 2012 and identified in February 2016. The aphid seems to be responsible for needle discoloration and premature senescence, symptoms observed since spring 2008 on the infested pines. These clusters of P. nigra subsp. mauretanica trees are protected by park regulations, and given their conservation status further investigations into this pest species, and other biotic and abiotic factors that may threaten this important tree, are required. 相似文献
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基于被动微波遥感的积雪深度反演 总被引：1，自引：0，他引：1
利用北疆地区2009-2010年积雪季(12-2月)AMSR_E降轨数据19GHz与37GHz波段的水平极化亮温数据,结合北疆地区60个气象台站的实测雪深数据,建立了北疆地区基于AMSR_E亮度温度数据的雪深反演模型。对模型精度进行评价,结果显示:雪深在3-10cm时,模型反演的雪深值负向平均误差为-4.8cm,RMSE值为4.1cm;雪深在11-30cm时,模型反演雪深值的平均误差仅为-0.2cm,RMSE、正向平均误差、绝对平均误差均较小;雪深大于30cm时,模型反演的雪深值负向平均误差较小,其他各项误差较大。与实测值进行对比,模拟结果同台站观测情况基本一致。 相似文献
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Based on a long-term field investigation and other research results,we reviewed the status and distribution of ungulates in Xinjiang,China. The ungulates in Xinjiang included 19 ungulate species(30 subspecies) from 6 families and 2 orders. Among them,3 species(2 subspecies) relate to Equidae(Perrisodactyla) ,and 16 species(28 subspecies) are from 5 families of Artiodactyla. In this paper,we analyzed the conservation status of most rare and important 13 ungulate species. Firstly,we proposed the protection of genetic diversity of Camelus ferus and the distribution areas of Moschus sifanicus,Procapra przewalskii and Saiga tatarica in Xinjiang. We found that Moschus sifanicus but not Procapra przewalskii distributed in Xinjiang. It was not clear whether the remnant populations of Saiga tatarica existed in Xinjiang and China-Kazakhstan border or not. We discussed that the protection level and rational use of Capra sibirica and enhancing protection level and enlarging monitoring and research projects for Pantholops hodgsoni and Gazella subgutturosa. And we would like to suggest Forestry Department to develop the captive breeding of Tibetan antelope for rational use. In addition,the captive breeding of Cervus elaphus in Xinjiang was reviewed. Local government should lessen strong control to Cervus elaphus because of many breeding centers' establishment. 相似文献
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松褐天牛的天敌及其对寄主的控制能力研究 总被引：4，自引：0，他引：4
根据国内外的研究和作者的研究结果,总结和记述了传播松材线虫的媒介昆虫松褐天牛的天敌种类及其控害情况。共有9 7种天敌,其中天敌昆虫4 7种,病原微生物1 7种,捕食性鸟类3 3种。同时对主要天敌种类病原微生物、肿腿蜂、斑头陡盾茧蜂、花绒寄甲、天牛斑叩甲和捕食性鸟类对松褐天牛的控制能力进行了阐述。 相似文献
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乌鲁木齐及附近地区蚁科区系的初步调查 总被引：4，自引：0，他引：4
对乌鲁木齐及附近地区蚁类的调查表明 ,计有 2亚科 1 3属 37种 ;区系组成以蚁属FormicaL .和弓背蚁属CamponotusMayr的种类较为丰富 ,分别有 1 5种和 6种 ;区系成分较为复杂 ,含古北种、新北种和广布种 ,其中 ,古北种有 30种 ,占总数的 81 % ;古北种下含泛古北种、中亚细亚种、欧洲种、欧洲中亚种、特有种、地中海种、欧洲—西伯利亚种、中央亚细亚种 ,而泛古北种最多 ,达 1 2种 ,占 32 .4 % ;其次为中亚细亚种有 7种 ,占 1 8.9% ;在所记录的种类中 ,草地蚁Formicapratensis,小林蚁 F .polyctena等多为中生性的种类 ,主要分布于森林地带或林间草地 ;草原箭蚁C .aenescens,草原原蚁P .epinotalis多分布在荒漠、半荒漠地带 ;褐色收获蚁Messorclivorum为乌鲁木齐地区的优势种 ,较为广泛地分布于乌鲁木齐及周边地区 相似文献
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Luigi Faino Valeria Scala Alessio Albanese Vanessa Modesti Alessandro Grottoli Nicoletta Pucci Andrea Doddi Alessia L’Aurora Giuseppe Tatulli Massimo Reverberi Stefania Loreti 《Plant pathology》2021,70(8):1860-1870
Xylella fastidiosa (Xf) is a gram-negative bacterial plant pathogen that can infect over 500 plant species. While it is endemic in America, X. fastidiosa subsp. pauca was reported for the first time in Europe in 2013 on olive trees in southern Italy. The availability of fast, sensitive, and reliable diagnostic tools is indispensable for managing current and future outbreaks of Xf. In this paper, we use the OXford Nanopore Technologies (ONT) MinION platform for detecting and identifying Xf at species, subspecies, and sequence type (ST) level. Two workflows were developed: the first one provided a “shotgun” strategy, that is, exploring the possibility of detecting Xf within DNA extracted from plant samples. This allowed detection of Xf by direct DNA sequencing and identifying the subspecies only in samples with high bacterial levels. Nanopore amplicon sequencing was pursued as a second workflow. This consists of PCR amplification of a set of seven multilocus sequence typing (MLST) fragments, officially adopted for identifying Xf at type strain level, followed by Nanopore-sequencing of the amplicons and an ad hoc pipeline to generate MLST consensus calls. This combined approach, which takes only a few hours, allowed the detection and identification of Xf at ST level in plant material with low bacterial infection. 相似文献