小麦赤霉病禾谷镰孢菌生物基增效剂的筛选

[目的]探明苦参、黄岑片、丹参等9种中药提取物对小麦赤霉病菌禾谷镰孢菌(Fusarium grami-narum Schw)的敏感性及抑菌活性较高中药提取物与防控效果较好的化学农药复配后对小麦赤霉病菌禾谷镰孢菌的毒力,为小麦赤霉病防控上抑菌活性较好的生物基增效剂的选择提供科学依据.[方法]通过室内毒力测定法,测定9种中...     

薄皮甜瓜新品种龙庆5号的选育

龙庆5号是以07-91-10为母本,以MN-100为父本配制而成的适宜保护地栽培的薄皮甜瓜杂交种。黑龙江省冷棚栽培全生育期80d左右,子孙蔓均可结瓜,结瓜能力强,果实膨大速度快。成熟瓜高圆形,白绿色润黄,果面光滑耐贮运,果味清香,中心可溶性固形物含量11.02%,单果质量400～450g。黑龙江省冷棚栽培667m2产量3000kg左右。     

植物多糖提取技术的研究进展

植物多糖是普遍存在于自然界的由许多相同或不同的单糖以α-或β-糖苷键所组成的化合物。植物多糖作为一类重要的天然活性物质,其最大优点是毒副作用小,来源广泛,因此其应用具有广阔的发展前景。本文论述了近年来植物多糖的提取方法的研究进展,并对植物多糖前景进行展望。     

基于集合经验模态分解算法的土壤肥力胁迫甄别与监测

土壤肥力是农作物生长所需的关键要素之一,其水平直接影响农作物的长势甚至产量,然而作物生长过程中受多种胁迫因素的综合影响。避免土壤肥力监测结果受到其他胁迫因素的干扰是土壤肥力精准监测的关键问题之一。该研究旨在分析利用集合经验模态分解（Ensemble Empirical Mode Decomposition,EEMD）算法进行土壤肥力胁迫甄别和监测的可行性。以河北省廊坊市大厂县冬小麦耕地为研究区域,以EEMD算法为基础,将分解后的本征模函数（Intrinsic Mode Function,IMF）分量按照年际、年间和年内的尺度进行合成,结合不同的时间尺度及胁迫特征剔除土壤水分胁迫、病虫害胁迫及重金属胁迫等因素,实现对土壤肥力胁迫的有效甄别提取。结合主成分分析相关方法,将有机质、全氮、有效磷以及速效钾4项养分指标转换为3个主成分,初步得到土壤肥力综合评价简易模型,后与分解结果进行拟合,构建并实现了土壤肥力综合水平的定量评价模型。结果表明：1）在年际、年间以及年内3组波动组分中,年际波动组分可以较好地反映研究区内土壤肥力胁迫作用对农作物长势的影响;2）利用最小二乘法对土壤养分指标测定数据进行线性拟合,拟合结果与原始数据的决定系数达到了0.857,能够较好地反映出原始数据的变化水平;3）最终土壤肥力水平评价模型评价结果与实测结果间的平均误差为11.82%,表明模型预测结果与实际情况契合程度高,模型反演结果能够较好地反映研究区的土壤肥力水平。该研究结合EEMD算法与统计学分析实现了土壤肥力胁迫的有效甄别及土壤肥力定量评价模型的构建,为遥感技术在土壤肥力研究领域的应用提供了参考。     

生物炭对粉黏壤土水力参数及胀缩性的影响

该文选取2种粒径（细炭0.013～0.048 mm、粗炭0.3～0.7 mm）的生物炭,以2种质量百分比（3%、6%）施入一种粉黏壤土,通过测定不同粒径生物炭及施加比例下土壤的水分特征曲线、饱和水力传导度、收缩性及饱和膨胀率,研究生物炭对粉黏壤土水力参数及胀缩性的影响。结果表明,2种粒径及添加比例的生物炭均降低了粉黏壤土的持水能力。但4种添加生物炭处理相互之间持水能力差异不显著。生物炭可降低粉黏壤土中极微孔隙和中大孔隙的比例,提高微孔隙和小孔隙所占的比例。生物炭的添加降低了该粉黏壤土的饱和含水率和凋萎系数。细炭对粉黏壤土的田间持水率没有显著影响,粗炭降低了粉黏壤土的田间持水率。两种粒径的生物炭均可提高粉黏壤土的有效含水率,并降低离心失水过程中土壤的收缩,在这2方面细炭的影响效果比粗炭显著;细炭的添加对粉黏壤土饱和膨胀率没有显著影响,粗炭则降低了粉黏壤土的饱和膨胀率。2种粒径生物炭的添加均降低了该粉黏壤土的饱和水力传导度。3%和6%的添加比例在大部分研究指标中未表现出明显差异。该研究可为生物炭在土壤环境修复应用方面提供一定的理论指导。     

Prevalence,Molecular Characterization and Antimicrobial Resistance of Thermophilic <Emphasis Type="Italic">Campylobacter</Emphasis> Isolates from Cattle,Hens, Broilers and Broiler Meat in South-eastern Italy

Eleven cattle farms, 8 layer farms, 7 broiler farms and 30 broiler meat samples were investigated in south-eastern Italy throughout 2003 to evaluate the prevalence, the molecular type and antimicrobial resistance of thermophilic Campylobacters. A total of 398 samples were analysed. One Campylobacter isolate for each positive faecal swab and three isolates per positive broiler meat sample were selected for further analysis. Multiplex PCR was performed for species-level identification and PCR-RFLP of the flagellin A gene for genotyping. Resistance to 14 antimicrobials was studied in 188 Campylobacter isolates. Prevalence of campylobacters was high both on farms (100%) and in food samples (73%). On 4/11 cattle farms and on 10/15 poultry farms more than one species was isolated. The presence of more than one genotype was found on 8/11 cattle farms, on 10/15 poultry farms and in 8/22 Campylobacter-positive food samples. High rates of resistance to quinolone were observed: 9/31 (29%) C. jejuni bovine isolates, 4/22 (18%) C. jejuni poultry isolates, and 14/26 (54%) C. coli poultry isolates. Resistance to sulphamethoxazole-trimethoprim was also observed frequently: 18/26 (69%) of the avian C. coli strains, 25/31 (80%) of the C. jejuni strains isolated from poultry and 15/22 (68%) of those isolated from cattle were resistant. There was a significant difference between the rate of resistance to macrolides of C. coli and C. jejuni isolated in poultry, which amounted to 23% and 3%, respectively. This study provided data on the prevalence and antimicrobial resistance of thermophilic campylobacters in south-eastern Italy and confirmed that flaA-typing is an efficient tool to study the epidemiology of Campylobacter strains in short-term investigations.     

“赤霞珠”发酵不同阶段去籽对葡萄酒品质的影响

以宁夏贺兰山东麓主栽葡萄品种"赤霞珠"为试材,采用传统酿造工艺,双层筛网去籽,研究了不同去籽处理(早期去籽、中期去籽、后期去籽、以不去籽为对照)对葡萄酒理化性质和品质的影响。结果表明:不同处理条件下葡萄酒常规理化指标与柔和指数无显著性差异;不同处理对葡萄酒总酚、单宁、总花色苷、色度和明胶指数均产生影响,表现为葡萄籽参与发酵时间越长,葡萄酒中总酚、单宁、总花色苷、色度以及明胶指数越高;色调除对照外,其它处理无显著性差异。综合品评结果可知,发酵结束后去籽的葡萄酒品质最好、酒体结构感强、酒体饱满度及复杂度较好。     

观赏荷花新品种‘宝莲灯’

观赏荷花‘宝莲灯’由‘红灯高照’荷花种子经60Co辐照诱变后人工选育获得的新品种。植株小微型,立叶高40~49 cm,叶长径20~24 cm,短径18~20 cm。花朵繁密,单盆开花17~25朵。花重台,花径10~11 cm,粉红色,花瓣100~120枚。雄蕊及雌蕊瓣化,不结实。     

Seroprevalence for norovirus genogroups GII and GIV in captive non‐human primates

Noroviruses (NoVs) are a major cause of epidemic gastroenteritis in children and adults. Several pieces of evidence suggest that viruses genetically and antigenically closely related to human NoVs might infect animals, raising public health concerns about potential cross‐species transmission. The natural susceptibility of non‐human primates (NPHs) to human NoV infections has already been reported, but a limited amount of data is currently available. In order to start filling this gap, we screened a total of 86 serum samples of seven different species of NPHs housed at the Zoological Garden (Bioparco) of Rome (Italy), collected between 2001 and 2017, using an enzyme‐linked immunosorbent assay (ELISA) based on virus‐like particles (VLPs) of human GII.4 and GIV.1 NoVs. Antibodies specific for both genotypes were detected with an overall prevalence of 32.6%. In detail, IgG antibodies against GII.4 NoVs were found in 18 Japanese macaques (29.0%, 18/62), a mandrill (10.0%, 1/10), a white‐crowned mangabey (16.6%, 1/6) and in an orangutan (33.3%, 1/3). Twelve macaques (19.3%, 12/62), five mandrills (50.0%, 5/10), two chimpanzees (100%, 2/2) and a white‐crowned mangabey (16.6%, 1/6) showed antibodies for GIV.1 NoVs. The findings of this study confirm the natural susceptibility of captive NHPs to GII NoV infections. In addition, IgG antibodies against GIV.1 were detected, suggesting that NHPs are exposed to GIV NoVs or to antigenically related NoV strains.     

种植密度和顶端调节剂对烤烟质体色素及其降解产物的影响

以烤烟品种吉烟九号(当地主栽品种)为试材,于2008-2009年采用种植密度和顶端调节剂二因素裂区试验设计,研究了种植密度和顶端调节剂(自制)对烤烟质体色素及其降解产物含量的影响.结果表明,种植密度和顶端调节剂及其两者互作对叶绿素和类胡萝卜素及其降解产物均有极显著影响.随着种植密度的减小,叶绿素含量先降低再升高,类胡萝...