速生耐寒邓恩桉在桉树分布北缘区的适生性     

刘友全  李志辉  马英  杨模华  贺菊红  张斌 《中南林业科技大学学报(自然科学版)》2007,27(2):66-69

桉树E uca lyp tus为世界热带、亚热带地区的极有价值的造林树种.对邓恩桉在湘中地区引种后的生长情况进行调查.结果表明:在桉树引种北缘区,邓恩桉年平均高生长为2.3~3.0 m,胸径生长2.2~3.0 cm,表现出一定的抗瘠薄能力、抗寒耐寒性和速生性.扼要地总结了邓恩桉种苗繁殖技术的进展,并就存在的问题提出了解决方法.  相似文献   

桉树立地生产力与养分生产力参数的确定   总被引：9，自引：0，他引：9  

吴晓芙  胡曰利 《林业科学》2003,29(2):71-77

桉树试验林样本分析结果表明，桉树树杆中氮，磷，钾养分浓度的倒数与养分吸收量早明显的负线性相关。基于这一相关性，对实测的数据作回归分析。估测的立地生产力极限和养分生产力参数值，以及相应的立地养分效应曲线具有较高的精确度。本文为研究林木生长和营养的动态函数关系提供了新的思路和方法。  相似文献   

Characterization of an intravenous lipopolysaccharide inflammation model in calves with respect to the acute-phase response     

《Veterinary immunology and immunopathology》2015,163(1-2):46-56

Our objective was to develop a lipopolysaccharide (LPS) inflammation model in calves to evaluate the acute-phase response with respect to the release of pro-inflammatory cytokines and acute-phase proteins, fever development and sickness behaviour. Fourteen 4-week-old male Holstein Friesian calves were included and randomly assigned to a negative control group (n = 3) and an LPS-challenged group (n = 11). The latter received an intravenous bolus injection of 0.5 μg of LPS/kg body weight. Blood collection and clinical scoring were performed at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 12, 18, 24, 28, 32, 48, 54 and 72 h post LPS administration (p.a.). In the LPS group, the following clinical signs were observed successively: tachypnoea (on average 18 min p.a.), decubitus (29 min p.a.), general depression (1.75 h p.a.), fever (5 h p.a.) and tachycardia (5 h p.a.). Subsequent to the recovery from respiratory distress, general depression was prominent, which deteriorated when fever increased. One animal did not survive LPS administration, whereas the other animals recovered on average within 6.1 h p.a. Moreover, the challenge significantly increased plasma concentrations of tumour necrosis factor-α, interleukin 6, serum amyloid A and haptoglobin, with peaking levels at 1, 3.5, 24 and 18 h p.a., respectively. The present LPS model was practical and reproducible, caused obvious clinical signs related to endotoxemia and a marked change in the studied inflammatory mediators, making it a suitable model to study the immunomodulatory properties of drugs in future research.  相似文献   

松毛虫早期灾害点遥感监测研究初报   总被引：7，自引：1，他引：7  

武红敢  严小君 《林业科学》1995,31(4):379-384

松毛虫早期灾害点遥感监测研究初报武红敢，黄建文，乔彦友（中国林业科学研究院资源信息所北京１００００１）严小君，陈林洪（浙江省江山市森林防疫站江山３２４１００）关键词松毛虫害，ＴＭ数据，影像，监测松毛虫为我国最为严重的森林害虫［１］。几十年来，各级政府...  相似文献   

南极磷虾渔船船速对科学探鱼仪有效探测深度的影响     

王新良  于小涛  张吉昌  李显森  赵宪勇 《水产学报》2022,46(3):505-512

渔业资源声学调查评估的基本条件之一是科学探鱼仪的有效探测深度可以覆盖目标的主要分布水层.针对利用渔船采集声学数据开展南极磷虾资源调查评估,本研究基于后处理方法获得声学数据背景噪声强度,建立一种科学探鱼仪有效探测深度的评估方法,并以南极磷虾渔船"福荣海"轮为例,评估船速变化对该船船载Simrad EK60型科学探鱼仪(3...  相似文献   

An enrichment microsphere immunoassay for the detection of <Emphasis Type="Italic">Pectobacterium atrosepticum</Emphasis> and <Emphasis Type="Italic">Dickeya dianthicola</Emphasis> in potato tuber extracts     

Jeroen Peters  Wojciech Sledz  Jan H. W. Bergervoet  Jan M. van der Wolf 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(2):97-107

An enrichment microsphere immunoassay (MIA) was developed, based on the Luminex xMAP® technology, for the simultaneous (duplex) detection of Pectobacterium atrosepticum (former name Erwinia carotovora subsp. atroseptica) (Pca) and Dickeya dianthicola (former name Erwinia chrysanthemi) (Dcd) in potato plant extracts. Target bacteria in the extracts were enriched for 48 h in a semi-selective broth containing polypectate under low oxygen conditions. Samples were subsequently incubated with antibody-coated colour-coded microspheres (beads) and with secondary antibodies conjugated with Alexa Fluor® 532, a reporter dye. Samples were analyzed with the Luminex analyzer, in which one laser identified each microsphere and another laser the reporter dye conjugated to the secondary antibodies. The assay required minimal sample preparation, could be completed in 1 h, was performed in 96 wells microtitreplates and required no wash steps. The limit of detection for the duplex enrichment MIA was 100–1000 cfu ml^?1, which was a hundred times lower than of an enrichment-ELISA. Without enrichment, the sensitivity of MIA and ELISA was largely similar and ranged between 10⁶ and 10⁷ cells ml^?1. No difference in sensitivity was found between a MIA in a single or duplex format. In a comparative test with non-infected potato plant extracts and extracts from plants infected with Pca or Dcd, results of the enrichment MIA correlated well with those of the enrichment ELISA and enrichment PCR. These results indicate that MIA can be reliably used for multiplex detection of soft rot Enterbacteriaceae in crude potato plant extracts. The technology is an attractive and cost-effective alternative to other detection methods, including ELISA.  相似文献   

一起猪流行性腹泻病毒与博卡病毒混合感染病例分析     

朱小甫  吴旭锦  郑红青  尹宝英 《陕西农业科学》2022,(1):79-80

陕西渭南某猪场发生了一起仔猪腹泻病例,通过临床症状观察、病理解剖、细菌分离以及病原RT-PCR检测,确诊为一起流行性腹泻病毒混感博卡病毒病例。针对发病原因提出了防治措施,为防控仔猪腹泻提供参考。  相似文献   

草莓种子实生苗的病毒分子检测     

缪军  马秀明  孙杨  兰成云  王俊峰  韩伟 《现代农业科技》2022,(2)

草莓易感染病毒,从而导致产量减少和品质下降。目前生产上主要采用茎尖组织培养脱毒的方法,并不能保证完全脱除病毒,还需要进行无病毒检测鉴定。因此,需进一步探索简便、高效、免检的脱毒体系。利用RT-PCR技术,以草莓肌动蛋白基因序列为内标,结合4种草莓病毒特异性扩增,验证了草莓种子实生苗不携带病毒。旨在助推种子繁殖型草莓品种的应用。  相似文献   

抗旱王牛的血细胞及生化指标的测定研究     

孙晓燕  黄德均  蒋安 《中国牛业科学》2014,(4):33-36

[目的]为了掌握引进的抗旱王牛的血液理化指标。[方法]使用全自动分析仪,选择成年的雌性抗旱王牛和雌性西门塔尔牛各14头,测定了30项血液理化指标,并进行统计分析。[结果]检测结果如下：抗旱王牛的30项血液理化指标中有73.33%（22/30）的指标变异系数小于20%,有20.00%（6/30）的变异系数介于20%～30%,有6.67%（2/30）的变异系数超过30%;西门塔尔的30项血液理化指标中有70.00%（21/30）的指标变异系数小于20%,有20.00%（6/30）的变异系数介于20%～30%,有10.00%（3/30）的变异系数超过30%。西门塔尔牛的LYM水平显著高于抗旱王牛（P〈0.05）;抗旱王牛的GGT、TCHOL、BU、TG水平显著高于西门塔尔牛（P〈0.05）。其他指标差异不显著。[结论]抗旱王牛血液理化测定指标相对较稳定,初步体现了其抗旱耐热的品种特性,但其他特性与优点的体现仍需进一步研究。  相似文献   

口蹄疫病毒解旋酶恒温扩增检测方法的建立     

金静维  马保华  邱索平  凌彬冰  李贺  胡晓冰  曹永长  薛春宜 《贵州畜牧兽医》2014,(5):1-5

  相似文献