河套苹果梨不同行间套作物昆虫群落结构分析     

陈培民  王建民  钟延平  达愣  刘双平 《内蒙古农业大学学报(自然科学版)》2003,24(4):64-69

通过对河套苹果梨产区不同果园行间套作物内昆虫群落调查,结果表明,河套地区果园天敌昆虫资源丰富。果园中主要害虫为害、益害虫比值及多样性指数与当地果园化学喷施次数密切相关;果树行间套种适宜作物或适宜种草有利于天敌昆虫的栖息,促进天敌昆虫数量的增加。  相似文献   

Lamellar perfusion and energy metabolism in a preferential weight bearing model     

Andrew W. van Eps  James K. Belknap  Xavier Schneider  Darko Stefanovski  Julie B. Engiles  Dean W. Richardson  Steven T. Zedler  Carlos E. Medina-Torres  Mauria R. Watts 《Equine veterinary journal》2021,53(4):834-844

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Rodent hosts and flea vectors in Brazilian plague foci: a review     

Diego Leandro REIS DA SILVA FERNANDES  Matheus FILGUEIRA BEZERRA  Marise SOBREIRA BEZERRA DA SILVA  Nilma Cintra LEAL  Christian Robson DE SOUZA REIS  Alzira Maria Paiva DE ALMEIDA 《Integrative zoology》2021,16(6):810-819

Plague, caused by the Yersinia pestis bacterium, has several foci scattered throughout a large area from the Brazilian territory that ranges from the Northeastern State of Ceará to the Southeastern State of Minas Gerais and another separated area at the State of Rio de Janeiro. This review gathers data from plague control and surveillance programs on the occurrence and geographic distribution of rodent hosts and flea vectors in the Brazilian plague areas during the period of from 1952 to 2019. Furthermore, we discuss how the interaction between Y. pestis and some rodent host species may play a role in the disease dynamics. The absence of human cases nowadays in Brazil does not mean that it was eradicated. The dynamics of plague in Brazil and in other countries where it was introduced during the 3rd pandemic are quite alike, alternating epidemics with decades of quiescence. Hence, it remains an important epidemic disease of global concern. The existence of a large animal reservoir and competent vectors demonstrate a need for continuous surveillance to prevent new outbreaks of this disease in humans.  相似文献   

Vertical SOC distribution and aromatic carbon in centuries old charcoal-rich Technosols     

Alexander Bonhage  Thomas Raab  Anna Schneider  Thomas Fischer  Shaghayegh Ramezany  William Ouimet  Alexandra Raab  Florian Hirsch 《European Journal of Soil Science》2022,73(4):e13293

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极晚熟杏品种‘冬杏’花粉活力及柱头可授性研究     

赵世荣  廖康  达梦香  徐桂香  徐乐  董胜利  杜润清 《农业科学与技术》2015,(5)

[目的]了解‘冬杏’的花器官发育特性及其与其它杏品种间的差异。[方法]观察和测定冬杏和其它杏品种的花器官形态、花粉量、花粉活力、柱头可授性。[结果]‘冬杏’中长花柱比率82.4%,雌蕊退化率较低。花粉量为32183.2粒/花,含量较低。离体花粉培养最适培养基为1%琼脂+15%蔗糖+0.01%硼酸,花粉萌发率为53.0%,花粉活力相对偏低。从蕾期到开花花粉活力呈现先升高后降低的趋势,最大值出现在开花后1 d,离体花粉的活力随贮藏时间持续下降,在开花（贮藏）3 d后花粉萌发率下降至最大值的一半。柱头可授性先增强后减弱,开花后2h～4h柱头可授性极强。开花后1h至8h为‘冬杏’的适宜授粉期,略短于其它品种。[结论]‘冬杏’中长花柱比率较高,从蕾期到开花花粉活力呈现先升高后降低的趋势,开花后1h至8h为‘冬杏’的适宜授粉期。  相似文献   

Biomass, carrageenan yield and reproductive state of Hypnea musciformis (Rhodophyta: Gigartinales) under natural and experimental cultivated condition     

M. WALLNER  S. LOBO  N. BOCCANERA  E. MENDES DA  SILVA 《Aquaculture Research》1992,23(4):443-451

Cultivation of the macroalga Hypnea musciformis (Wulfen) Lamouroux was conducted from April 1987 to January 1988 at Praia do Forte (State of Bahia, Brazil), utilizing floating racks, Biomass, reproductive state, carrageenan yield and viscosity of algae artificially grown in situ were compared with those from natural populations. Temperature, salinity, pH, dissolved oxygen, organic and inorganic suspended matter and phosphate in surface waters were similar in all experimental phases. Algae growing on the racks exhibited significantly higher daily biomass increase (0·94-9·69g/m²day dw) than plants from natural reefs (1·39-1·74g/m²/day dw). Cultivated algae presented a dominance of tetrasporic stages, while algae from the reefs had a high occurrence of vegetative stages. Both cultivated and natural plants showed higher numbers of cystocarpic specimens during the summer. Carrageenan yield of cultivated plants was significantly higher than those growing under natural conditions only during summer-time experiments, presenting values of 3972% and 38-28% for experiments and a range of 22·7-34·88% for the reef plants. However, carrageenan viscosity of cultivated algae was always higher (40·33 ± 4·62 centipoise) and less variable than that found for the reef growing algae (35·71 ± 19·92 centipoise).  相似文献   

Clinical Outcome After Intra‐Articular Administration of Bone Marrow Derived Mesenchymal Stem Cells in 33 Horses With Stifle Injury     

Dora J. Ferris DVM  David D. Frisbie DVM  PhD  Diplomate ACVS  John D. Kisiday PhD  C. Wayne McIlwraith BVSc  PhD  DSc  Diplomate ACVS  Brent A. Hague DVM  MS  Diplomate ACVS & ABVP  Michael D. Major DVM  MS  Diplomate ACVS  Robert K. Schneider DVM  MS  Diplomate ACVS  Chad J. Zubrod DVM  MS  Diplomate ACVS  Christopher E. Kawcak DVM  PhD  Diplomate ACVS  Laurie R. Goodrich DVM  PhD  Diplomate ACVS 《Veterinary surgery : VS》2014,43(3):255-265

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Immunogenicity of a Recombinant Mycobacterium smegmatis Vaccine Expressing the Fusion Protein CMX in Cattle from Goiás State, Brazil     

Duanne ALVES DA SILVA  Marcos Ant?nio Rocha CAVALCANTI  Fábio MUNIZ DE OLIVEIRA  Monalisa Martins TRENTINI  Ana Paula JUNQUEIRA-KIPNIS  André KIPNIS 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(7):977-984

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浙江天童灌木层树种个体生物量分配及模拟   总被引：1，自引：0，他引：1  

夏晨诚  杨同辉  曹菁  赵琦  林波  达良俊 《安徽农业大学学报》2014,41(6):945

根据不同生活型树种标准木实测数据,比较个体生物量器官分配状况以探索其生长策略;同时建立了该地区灌木层主要树种的生物量回归模型,并与全收割法测量数据比较,检验模型估算精度。结果表明,相对常绿树种,天童灌木层落叶树种分配较多的生物量于地上部分来获取更多光照资源以满足自身生长需要;灌木树种分配较多生物量于树叶,相比之下,乔木树种则更多地累积树干和根系生物量;各生活型树种器官生物量模型以幂函数为主,树干和地上部分模型拟合度最好;应用于样地生物量估算,树干模型精度最高,树叶模型精度最低;地上部分生物量回归模型能较为准确地估算灌木层生物量,与实测值误差仅为0.47 %,表明该模型适用于地区灌木层生物量的测算。  相似文献   

牛BMP-15基因cDNA的克隆和序列分析     

祁云霞  王峰  刘永斌  田蕾  董文杰  达赖  田春英  荣威恒 《华北农学报》2007,22(4):63-66

BMP-15基因主要在哺乳动物卵巢中表达,对卵泡的发育和分化起重要作用,克隆了牛BMP-15成熟肽编码区的cDNA序列并进行序列分析,旨在为BMP-15在牛繁殖性能方面的进一步研究奠定理论基础。根据其他物种BMP-15基因的保守序列设计特异性引物,扩增牛的cDNA序列。从牛卵巢中提取总RNA,采用RT-PCR技术扩增出牛BMP-15cDNA序列。将此片段克隆到PMD18-T载体中,经菌落PCR鉴定和DNA序列测定分析验证,证实所克隆序列BMP-15为骨形态发生蛋白,符合骨形态发生蛋白基因的特征。序列分析表明,该cDNA包含有1 185 bp组成的开放读码框(ORF),该ORF编码394个氨基酸,与绵羊、猪、人、小鼠等动物氨基酸序列比对发现同源性分别为98.5%,87.6%,74.0%,69.4%。  相似文献