花生蛴螬空间分布型研究及药效评价方法探讨

花生蛴螬田间分布属于聚集分布。在已知的m m回归关系的基础上提出了不同密度下花生蛴螬的理论抽样数和防治花生蛴螬的田间试验方法 ,并对 2种药效计算方法进行了评价。     

闽南旱地作物蛴螬发生及防治的研究

通过金龟子成虫在黑光灯下和田间的消长调查、蛴螬的田间定期挖查 ,初步摸清了闽南地区危害花生、大豆、甘薯、甘蔗等旱地作物的蛴螬种类有 2 6种 ,主要种类有 9种。明确了其主要蛴螬种类的生活习性与旱地作物互为相关。通过采用不同的药剂与不同方法进行防治试验 ,筛选出经济有效的药剂种类 ,并根据不同作物的生长特性和不同蛴螬种类的危害特点 ,确定了经济有效的防治适期 ,并制定了相应的防治技术措施     

大黑蛴螬活动规律及对农作物幼苗的取食趋性研究

研究了不同龄期大黑鳃金龟Holotrichia oblita幼虫（蛴螬）的活动规律及其对6种农作物幼苗根部的取食趋性。大黑蛴螬的活动规律结果表明：各龄期大黑蛴螬均易趋向于幼苗根部寻找食物。采用双因素方差分析法研究取食时间和幼苗种类对大黑蛴螬取食趋性的影响。结果显示：除二龄外，一、三龄大黑蛴螬3 d后和6 d后在幼苗根部的虫量没有显著性差异；而在不同幼苗根部，各龄期大黑蛴螬的虫量均存在显著性差异。     

蛴螬化学成分和药理作用的研究进展

蛴螬在中医临床中有着悠久的应用历史,近年来,随着人们对蛴螬的深入研究,化学成分的研究也有了新进展,从蛴螬提取物分离出含氮类化合物、有机酸类化合物和甾体类化合物。在药理学方面,蛴螬提取物具有抗肿瘤、治疗口疮和眼部疾病等多种生物活性,是一种极具研究和开发价值的动物药。现将其近年来的化学成分、药理作用研究进展做一综述,以期为进一步开发利用提供参考资料。     

蛴螬天敌──食虫虻的生物学研究

过去文献曾报道食虫虹幼虫生活于土中捕食或腐食[1],也曾提及有可能捕食蛴螬[2],以及新种描述[3]和翅振[4],作者通过多年调查研究,首次提出了利用食虫虹幼虫对地下害虫蛴螬的生物防治,初步弄清了食虫蛇的生物学特性及其幼虫对蛴螬的控制效应和对麦苗的保护。通过多点大量调查,弄清了不同地势、不同土质、不同茬口对食虫虻幼虫分布的影响。人工放养观察结果进一步说明其在地下害虫生物防治方面的利用价值。现将近10年的研究结果报道如下。1试验方法及手段1．1生物学特性观察观将20cm×20cm×15cm的昆虫饲养缸3个置于室内,缸内装入经过…     

稀土元素对土栖动物群落结构的影响及对蛴螬的生态毒性

采用土施法和OECD推荐的滤纸接触法研究了稀土(ReCl₃·6H₂O)对豆田土栖动物群落结构的影响以及稀土对蛴螬的生态毒性.结果表明,对照与各处理之间动物种类数、主要动物种群数量、多样性指数差异均不显著;急性和慢性毒性试验表明,对照与各处理间的死亡率差异不显著.在稀土有效施用范围内,稀土对蛴螬的生态毒性很小,不会明显改变蛴螬种群结构.     

三化螟为害水稻白穗空间分布型及其应用

本研究探讨了水稻三化螟白穗空间分布格局和抽样技术,为该虫害的监测预报和有效防控提供参考.选取9块水稻田逐丛调查资料,应用6种聚集度指标、 Iwao的m~*—m回归分析法和Taytor幂法则,研究三化螟白穗的空间分布型和抽样技术.结果表明,三化螟白穗在水稻田呈聚集分布,分布的基本成分为个体间相互吸引,其聚集度是随着密度的增加而升高.在此基础上,采用Iwao法确定了三化螟白穗的田间最适理论抽样公式;田间调查时,可用白穗丛率估计白穗种群密度,其公式为■.所建立的理论抽样公式和简易估计公式可在三化螟白穗调查、监测预报和科学防控中推广应用.     

草坪地下害虫蛴螬的生物防治研究进展

蛴螬是草坪上最重要的一类地下害虫 ,对草坪的危害极大。文章综述了应用昆虫病原线虫、昆虫病原细菌、昆虫病原真菌、原生动物、昆虫病毒和寄生性、捕食性天敌昆虫等生防因子防治草坪害虫蛴螬的研究进展 ,并对未来草坪害虫蛴螬防治的研究发展方向做了一些探讨。     

高尔夫球场不同功能区草地蛴螬虫口密度及迁移动态研究

对亚热带地区3家高尔夫球场不同功能区草地蛴螬虫口密度及迁移动态进行了研究。结果表明,3家球场球道和果岭区草地蛴螬虫口密度及迁移动态明显受干湿季节、地形(区域)及养护水平的影响。雨季高地形(长草高地和短草高地)蛴螬虫口密度是旱季同地形蛴螬虫口密度近1倍,是雨季凹地形蛴螬虫口密度近数倍,而雨季凹地形(长草凹地和短草凹地)虫口密度则与此相反;旱季和雨季高水平养护区(短草高地和短草凹地)蛴螬虫口密度分别略高于粗养护区(长草高地和长草凹地);果岭蛴螬虫口密度变化除工区、Ⅱ区与球道区(长草高地和短草高地)相似外,Ⅲ区、Ⅳ区变化不明显,而且蛴螬数量很少。工区、Ⅱ区占整个果岭区蛴螬总密度约90％;果岭4区之间发生一定程度的蛴螬迁移,但局限在相邻区内,3天内2家球场迁移率平均为41．09％,相隔区迁移率为0,蛴螬迁移能被隔离措施完全阻隔;漆标记和隔离试验表明,4区蛴螬虫口密度显著性差异是果岭外部蛴螬迁入的结果;旱季球道区蛴螬主要分布于地下较深土壤中(5～11cm),雨季向地表位移(2～5cm),其中长草高地和短草高地年均入土较深,长草凹地和短草凹地入土较浅;果岭区蛴螬年均入土深度为球道区的一半左右,周年在0．3～7cm之间土层活动,9～10月接近地表活动(0．3～1cm)。     

竹小蜂幼虫空间分布型及抽样技术研究

竹小蜂幼虫空间分布型属于负二项分布;聚集度各指标测定结果表明,幼虫是聚集分布;经测定M^*=6．2836 0．3028^ˉx,屑于聚集分布。并用刀切法和F偏离度检验法对M^*进行了估计和检验测定为聚集分布。中分析并计算了林间调查的理论抽样数和序贯抽样决策,为今后该虫林间调查与防治提供了科学的依据。     

云南元阳梯田水稻田白背飞虱若虫空间分布型及理论抽样数

采用Taylor幂法扩散法和Iwao回归法分析了云南元阳哈尼梯田1400～2000m海拔16个哈尼族传统水稻品种田白背飞虱Sogatella furcifera(Horvath)1～3龄若虫的空间分布特征。结果表明,白背飞虱1～3龄若虫在不同海拔、不同水稻品种田均呈聚集分布中的负二项分布,其负二项分布的公共K值为3.53,聚集原因主要是由白背飞虱生物学特性和环境因素引起。Iwao直线回归方程拟合公式为m*=3.96+1.09m(R=0.97),Taylor幂拟合公式为lg(V)=0.28+1.34×lg(m)(R=0.85)。其中,在1400～1500、1501～1600、1601～1700、1701～1800、1801～1900和1901～2000m海拔梯田稻田中,白背飞虱若虫平均拥挤度分别为10.74±0.83、23.67±3.50、21.64±6.02、47.10±5.71、52.59±12.75、13.72±3.14,差异显著(F=5.77,P<0.01),其中在1701～1800和1801～1900m海拔稻田中白背飞虱平均拥挤度最高,表明在该海拔处白背飞虱在稻丛上分布较为集中,而在1400～1500和1901～2000m海拔稻田中平均拥挤度最低。根据空间分布型参数,建立了精度分别为0.1和0.2时的理论抽样数模型,分别为n=1905.43x+34.57,n=476x.36+8.64,该模型适用于不同虫口密度下的田间抽样。当白背飞虱虫口密度为5、10、20头/丛时,分别取样30、20和15个样方。     

Sequential sampling protocols for Spodoptera frugiperda (Lepidoptera: Noctuidae), on Zea mays fields: influence of sampling unit size

Spodoptera frugiperda (J.E. Smith) is a major pest in maize fields in Argentina. However, a sampling method that accounts for spatial pattern and allows reliable pest density estimations is still lacking. This paper addresses the issue of how sampling unit size can influence the characterization of S. frugiperda spatial pattern and the performance of sampling plans. An intensive sampling programme for S. frugiperda larvae was carried out in maize fields from October until March in four growing seasons. On each sampling date, 12 to 20 sampling units were taken at random. Each unit consisted of 1, 2, 4, 6, 8, 10 or 12 consecutive plants along a row. The linearized version of the Taylor's power law (TPL) was fitted to mean and variance estimated for each sampling date and data set through least squares regression. In general, b values from TPL were significantly >1 (P<0.05), indicating an aggregated sampling distribution. Regression slopes (b) ranged from 1.28 to 1.48 in small larvae and from 1.06 to 1.24 in large larvae, indicating stronger clumping in the former. TPL parameters were used to develop constant precision sampling plans. The efficiency of these plans in terms of expected total cost (searching and handling sampling units) was very sensitive to the size of the sampling units with small larvae but not with large larvae. The influence of sampling unit size and spatial pattern on TPL parameters and sampling costs is discussed.     

叶菜田节肢动物多样性系统调查与抽样技术研究

通过对以株和区组面积两种抽样单位，以随机取样和定点定株取样两种抽样方式下叶菜田节肢动物多样性测度的变异程度分析表现，在菜心田苗期以区组（０．１１ｍ＾２）为抽样单位，定苗后生长期～成熟期以株为抽样单位，采用随机抽样方式所获得的调查结果变异程度较小。在此基础上，通过对菜田节肢动物丰富度、多样性和均匀性等指标同样方数量间的关系分析表明，苗期、生长期、成熟期分别抽取１２、３０、２０个样方，可以达到各多样性     

Stability and Characteristics of Spatial Description Parameters for Nematode Populations

The parameters of Taylor''s Power Law (s² = am^b) relating variance (s²) to mean population level (m) were acceptably stable in different fields with similar cropping systems. Values of both a and b parameters varied with nematode species. The value of a was a function of sample size (number of cores) and was characterized for each species. The value of b was stable across sample size and reflective of the life history strategy of the species. The relationship between the economic threshold and sampling intensity required to allow management decisions, with specified levels of risk, indicated the need for improved sampling technology.     

荒漠绿洲过渡带植被空间异质性的可塑性面积单元问题

 以荒漠绿洲过渡带植被为研究对象,采用地统计理论与方法,以优势植物泡泡刺(Nitraria sphaerocarpa)和红砂(Reaumuria soongorica)种群为例,采用一个样地内2 500个10 m×10 m小样方中获取的植物盖度数据来研究采样尺度和划区方式对荒漠植被空间异质性的影响。其中尺度效应研究的思路是：一是保持粒度（样方）不变,增加幅度（样地）分析其对空间异质性的影响;二是保持幅度不变,改变粒度进行分析。划区效应是在样地尺度（500 m×500 m）上,把整块样地数据聚合成10 m×200 m、20 m×100 m、40 m×50 m、50 m×40 m、100 m×20 m和200 m×10 m等不同形状和不同方向的网格进行地统计分析。结果表明：荒漠绿洲过渡带植被空间异质性受采样尺度和划区方式影响显著。当样地面积小于200 m×200 m 时,所获取的数据不能真实反映泡泡刺种群的空间异质性;当样地面积小于100 m×100 m 时,所获取的数据不能真实反映红砂种群的空间异质性。调查泡泡刺和红砂种群的空间格局时,样方面积在20 m×20 m到30 m×30 m较为合适。植被空间异质性参数对划区方式的敏感性较强,其中泡泡刺种群的敏感性高于红砂种群。     

华北农牧交错带农田-草地界面土壤水分的空间特征

利用经典统计与地统计学方法,对华北农牧交错带农田-草地界面不同采样粒度（1 m×1 m、2 m×2 m）0～50 cm土层土壤水分的空间异质性进行了分析.结果表明：研究区农田、草地、农田-草地界面土壤水分均属中等变异,草地土壤水分的变异系数较农田大;土壤水分的变异系数随土层深度的增加而逐渐增大,且1 m×1 m采样粒度下农田-草地界面土壤水分变异系数与土壤深度呈显著相关(P＜0.05);1 m×1 m采样粒度下,农田-草地界面各土层土壤水分的空间异质性明显高于邻近的农田和草地,表现为中度到强度的空间自相关性,变程在7.65～30.99 m,且具斑块分布格局;2 m×2 m采样粒度下,农田-草地界面各土层土壤水分的空间结构既有中到强度的空间自相关性,又有完全随机化的纯块金效应,变程在4.16～18.86 m;在农田-草地边界存在土壤水分的界面效应.     

Electronic particle counting for evaluating the quality of air in operating theatres: a potential basis for standards?

Airborne particle counting in eight size ranges (0.5 → 20 μm), by computerized electronic equipment, was compared with the numbers of bacteria-carrying particles (BCP) assessed by slit sampling in ultra-clean and turbulently ventilated operating theatres. In the ultra-clean theatre the number of particles of 5–7 μm size range correlated with BCP while peaks in the numbers of particles <3 μm and > 15 μm corresponded with activity. Comparative relationships also occurred in the turbulently ventilated theatre but the use of this equipment in that environment cannot yet replace counts of airborne bacteria. We consider that electronic particle counting in the 0–20 μm size range may be used to judge the performance of a clean air operating theatre distribution system, including efficiency and integrity of the filter/seal systems and the presence or absence of entrainment of bacteria and other particles. The sampling techniques and analysis of particle concentration results described here may be a suitable basis for standards.     

Early deflections of cerebral magnetic responses to median nerve stimulation

We have recorded early components of somatosensory evoked magnetic fields with a sensitive 7-channel first-order gradiometer using a wide recording passband (0.05–2000 Hz) and high sampling frequency (8000 Hz). The left median nerve was stimulated at the wrist and responses were recorded over the right hemisphere. The responses typically consisted of a N20m peaking at 18–20 msec, a small P22m peaking at 21–23 msec and a P27m peaking at 29–31 msec. The topography of N20m could be explained by a tangential current dipole in the posterior wall of the central sulcus (probably in area 3b). The equivalent dipoles of P27m were located on average 10 mm antero-medially to the sources of N20m. This suggests that P27m may get a contribution from the anterior wall of the central sulcus. An increase of stimulus repetition rate from 2 to 5 Hz decreased the amplitude of P27m more than that of N20m, which implies that these two deflactions are generated by different neural netwoks.     

沿黄稻区灰飞虱越冬种群的时空分布及抽样技术研究

2009—2010年间系统调查了河南省境内沿黄稻区灰飞虱Laodelphax striatellus Fallén越冬种群的时空动态变化,并在田间调查的基础上,运用聚集度指标法和改进的Iwao回归分析法对沿黄稻区灰飞虱越冬种群的空间分布格局、理论抽样数及序贯抽样技术进行了研究。结果表明,灰飞虱在沿黄流域主要以少量3、4龄若虫进行越冬,11月下旬进入越冬期,翌年4月上中旬为越冬代种群发生高峰期,成、若虫虫量分别为22头/m2、43头/m2;灰飞虱成虫在5月中旬开始向水稻田迁飞,迁入高峰时虫量在450头/m2以上;灰飞虱越冬代成虫在麦田中空间分布型的聚集性指标大于1,空间分布型为聚集分布型,在此基础上得出灰飞虱田间调查的理论抽样数公式:N=t2/D2(0.324/m+0.086),并且描述了灰飞虱种群序贯抽样的Iwao模型:Tn=25n±15.4n~(1/2)。研究结果为田间灰飞虱的准确抽样调查和有效防治提供了科学依据。     

Evaluation of sequential sampling plans for the larger grain borer (Coleoptera: Bostrichidae) and the maize weevil (Coleoptera: Curculionidae) and of visual grain assessment in West Africa

Repeated sampling of rural maize stores in Benin was conducted to evaluate published parameters of a sequential sampling plan for a negative binomial distribution to determine pest status for Prostephanus truncatus (Horn) and Sitophilus zeamais Motschulsky. A computer program was used to rerandomize the data and evaluate the effects, in terms of average sample number and error rates, of different sampling plan parameter values. With respect to P. truncatus, lower and upper thresholds of 0.2 and 1.0 insects per ear and parameter values of k = 0.2 and alpha = beta = 0.1 were found to be adequate. With respect to S. zeamais, lower and upper thresholds of 10 and 20 insects per ear and parameter values of k = 1.0 and i alpha = beta = 0.1 were found to be adequate. Simplified sampling rules were proposed in which 11 ears should be sampled and if no P. truncatus are found, the population is low; otherwise the Wald plan should be followed. Owing to the lower per capita rate of damage, effective simplified sampling rules for S. zeamais were difficult to construct. An evaluation of the visual assessment scale rising whole ears showed that a visual scale estimating percentage damage rather than percentage loss, might be easy to construct and preferable for traders. Further work is needed to improve the usefulness of the visual scale in pest management decision support.