THE COMPARISON OF SUCTION TRAP, STICKY TRAP and TOW-NET FOR THE QUANTITATIVE SAMPLING OF SMALL AIRBORNE INSECTS

The sticky trap and stationary aerial 'tow-net' catch insects which alight or fly on to them or are blown against them by the wind. It would be expected that such traps would be inefficient in light winds or in calm weather; and even though their efficiency should increase with stronger winds, errors of unknown magnitude may occur not only in estimations of density and of proportions of species in the air, but also with comparisons of actual catches. These errors are due to unknown degrees of weighting as the traps sample by means of a variable wind from a changing population density. The suction trap, on the other hand, samples a constant quantity of air in all relevant wind-speeds and does not appear to suffer so seriously from these disadvantages. It also works efficiently in perfectly calm weather when maximum densities of insects are often in the air.
The performances of the three traps in the field operating over a range of wind-speeds are described. Particular attention has been paid to aphids, for which the sticky trap and tow-net are generally used and for which the suction trap was primarily designed. Density estimates of these insects in winds below about 3 m.p.h. are much larger when calculated from suction trap catches as compared with estimates from sticky trap and tow-net catches. There is reason for the belief that the suction trap is neither attractive nor repellent to aphids to a significant extent, and that it catches these insects at random by virtue of its air stream alone; weighting of catches due to variable quantities of air being sampled does not occur. It is considered, therefore, that the suction-trap values of density are likely to be the more accurate ones. Sampling of other small insects is also discussed.     

THE DEVELOPMENT OF LARGE SUCTION TRAPS FOR AIRBORNE INSECTS

Small suction traps for estimating the density of airborne insects, and its fluctuations, in relatively sheltered situations, e.g. in crops, have already been designed and used.
Larger, more powerful traps have now been developed for use in more exposed situations where insect densities are very low, or where winds are relatively strong, e.g. high in the air. Because of the large sample obtained they also enable very short-term density fluctuations to be followed.
The radical modifications of design and the special problems encountered in the operation of very large traps are described.     

LIME GREEN LIGHT-EMITTING DIODE EQUIPPED YELLOW STICKY CARD TRAPS FOR MONITORING WHITEFLIES, APHIDS AND FUNGUS GNATS IN GREENHOUSES

Abstract  Light-emitting diodes (LEDs) were attached to plastic cup and sticky card traps to improve pest insect catches in the laboratory and in greenhouses. Plastic cup traps equipped with 530 nm lime green LEDs caught more adult Trialeurodes vaporariorum (Westwood) and Bemisia tabaci (Gennadius) biotype B compared with plastic cup traps alone. Yellow sticky card (YC) and clear plastic sticky card (CS) traps equipped with lime green LEDs (LED-YC and LED-CS, respectively) caught more adult T. vaporariorum, B. tabaci biotype B, Aphis gossypii (Glover) and Bradysia coprophila (Lintner) compared with unlit traps of each type in greenhouse cage studies with shell beans, Phaseolus vulgaris (L.) and cotton, Gossypium hirsutum (L.). The lime green LED equipped YC traps have potential for use in greenhouses for insect detection, monitoring, and control.     

应用附加绿黄色光二极管的黄色胶片监测温室中的粉虱、蚜虫和蕈蚊

绿黄色光二极管(LED)附加在塑胶杯和胶片捕捉器可增加捕捉实验室和温室中昆虫的数量。附加有530nm绿黄色LED的塑胶杯捕捉器比没有附加的捕捉到更多的Trialeurodes vaporariorum(Westwood)和Bemisia tabaci(Gennadius)B生态型。在温室中昆虫笼以四季豆和棉花试验,附加有530nm绿黄色LED的黄色胶片(YC)和透明塑胶片(CS)分别缩写为LED—YC和LED—CS)比每一种没有附加的捕捉器捕捉到更多的T.vaporariorum,B．tabaci B生态型,Ahis gossypii(Glover)和Bradysia coprophila(Lintner)成虫。绿黄色LED—YC在温室中有用为监测和控制的潜在性。     

THE STANDARDIZATION OF AIR-FLOW IN INSECT SUCTION TRAPS

The air-flow and its variations in sixteen insect suction traps of five different types have been measured, using regularity of air sample size as the criterion of efficiency. Traps with the air-filtering cone enclosed in a cylinder and using axial flow fans with single-phase capacitor-start-and-run or three-phase motors are most efficient and can have normal working limits of + 4 % of the mean air delivery.
However, for smaller traps which are to be used only close to the ground or in cover, the original type with exposed cone and shaded-pole motor is quite satisfactory provided certain precautions are taken. Normal working limits of 5 8 % are then obtained.
These errors are derived in detail and the expected errors in more extreme conditions and with other traps are indicated.     

一种确定rm的简单方法的验证与分析

本文对一种测定蚜虫和螨的内禀增长率(rm)的简单方法进行了验证与分析。这种方法不要求详细的生殖力表资料,计算rm的公式如下:rm=0.74 ln(Md)/d。式中,d表示生殖前期,即从出生到第一次生殖之间的天数;Md表示在2d期间每个雌虫繁殖的平均雌性后代数。这种方法是Wyatt和White提出的。我们的研究表明:当Md小于1,这种方法不宜采用;当Md大于1和2d期间的繁殖贡献接近或大于70％时,可以用这种方法计算rm;不过,所有蚜虫和螨种群在2d期间对rm的繁殖贡献是否能够达到70％或70％以上还有待研究。研究繁殖分布特征对于这种简单方法的实际应用有重要意义。     

棉田棉铃虫卵抽样技术比较

本文对棉田棉铃虫卵抽样技术从两方面进行了比较,一系估值抽样方面:文中应用了简单随机抽样、阶层抽样、阶层抽样序贯估值与零频率抽样四种方法,并以估值的可靠性、代表性误差与抽样时间消耗三个指标进行了综合比较,结果认为以阶层抽样最佳.另一系风险决策抽样:本文应用了未着卵株的序贯抽样、阶层抽样、零频率抽样三种方法进行了综合比较,结果认为序贯抽样最佳,但若与零频率抽样相结合就既可迅速地作出风险决策又可获得虫口密度的信息.     

大渤海区海水入侵态势与防治构想

本文主要研究大渤海区海水入侵的若干问题及其对生态环境的影响和应采取的对策。大渤海区的山东、河北、辽宁、天津４省市沿海区,７０年代出现海水入侵后,发展速度相当快,且十分严重,结果使该地区土地生产力下降,工农业发展受阻,表生景观退化。仅莱州市７０年代末,海水入侵向内陆推移的速度为每年４６ｍ,而到８０年代末则增加到４０４ｍ,１０ａ扩大约８倍。鉴于此,应采取相应对策。     

COMPARISON OF THE EFFECTIVENESS OF TWO TRAPS FOR BACTROCERA TRYONI (FROGGATT) (DIPTERA: TEPHRITIDAE) AND IMPLICATIONS FOR QUARANTINE SURVEILLANCE SYSTEMS

The effectiveness of 2 traps for Queensland fruit fly, Bactrocera tryoni was compared for 1 year amongst relatively low populations at Applethorpe-Stanthorpe in southeast Queensland. The Lynfield trap which is an inexpensive, non-sticky, pot-type trap was significantly more effective than the Jackson trap and was at least as reliable in the detection of fruit fly populations. Use of Lynfield traps in quarantine surveillance programs should allow for a greater trap density and a more sensitive detection system to be established without vastly increased operational costs.     

随机与系统取样的生态学信息量比较

系统取样与随机取样是两种常用的取样方法。植被取样,也即是一有关植被数据的收集过程,通常采用系统取样的方法,其具有简便快捷易于操作的特点,但所获得的数据常是不甚妥当地应用于一些要求取样必须为随机的统计检验分析。随机取样从理论上来讲则是最理想的,但在植被实际调查过程中,真正达到随机取样的可能性较小。两者除了各自的统计学特点以及实际操作的可行性之外,在相同取样面积等条件下,所收集的数据所包含的生态学信息量是否显著不同,迄今鲜有报道。本文借助地理信息系统（ＧＩＳ）技术,以在海南霸王岭自然保护区所建立的永久样地为例,进行了计算机模拟的随机与系统取样。结果表明,在取样面积小于最小取样面积的范围内,随机取样在物种丰富度、种群密度、物种重要值等指标的测度上,在相同取样面积的条件下,所含信息量一般高于系统取样下所含信息;当取样面积较大时,两种取样方法所含的信息量则未有明显差异。     

稻茎毛眼水蝇幼虫田间分布型及抽样技术

根据14丘稻田稻茎毛眼水蝇幼虫调查资料．对其幼虫分布型进行了分析。结果表明;用I、CAm／m、Iσ四种聚集指标法测定,64．3％的田块呈随机分布．28．4%为均匀分布．7．3%为聚集分布。用Iwao平均拥挤度和Taylor幂法则测定．其田间分布型符合随机分布。用频次拟合法测验,50%的田块同时符合渡松、奈曼和负二项分布三种分布型;35．7%的田块同时符合2种分布型。根据该虫田间分布型的特点．制定了相应的序贯抽样技术。     

COMPARISON OF SIGMPLOT, PROBIT, AND EXTREME-VALUE METHODS FOR THE ANALYSIS OF THRESHOLD DATA

Two panels consisting of 12 and of 14 members, respectively,evaluated solutions of ethyl caprylate at different concentrationsto establish flavor detection thresholds. The resulting frequenciesof success at each concentration level were analyzed by a probitmethod and Drake's procedure (1975). These two methods in turnwere compared with extreme-value analysis. Agreement among thethree methods was good. The lowest threshold observed was 0.00069ppm and the highest, 26.9 ppm. An extreme-value plot is presentedfor 59 determinations obtained in prior studies and the 26 valuesof this study. The limitations and advantages of each methodof calculation are discussed as are precautions relative tothe way the extreme-value data should be accumulated or arrayedfor analysis. ^*Station Statistician, Georgia Agricultural Experiment Station.     

水溶性红曲黄色素的表征及其稳定性

以含硫化合物还原红曲色素,红斑素和红曲红素分子中的环羰基还原成羟基,得到水溶性红白曲黄色素.以 UV-Vis、IR和(?)H-~(13)CNMR对其结构进行了表征.该色素的吸光度随pH增大而略呈上升趋势,避光可明显提高其稳定性.除Mg~(2 )在pH9下使其溶液产生沉淀外,Sn~(2 )、Ca~(2 )、Fe~(3 )和AI~(3 )均不影响其稳定性.不同pH和温度下加热实验结果表明,酸性条件对其热稳定性影响较大.     

COMPARISON OF TWO SIMPLE METHODS FOR THE MEASUREMENT OF DETECTION THRESHOLDS FOR BASIC, UMAMI AND METALLIC TASTES

Two simple methods were followed to determine detection thresholds for the taste of substances in aqueous solution. The methods applied were: a modification of the ascending method of limits and a method based on the use of scales. Detection thresholds were calculated for the four basic tastes (sweet, salty, acid, and bitterness), umami and metallic. Reference substances for each taste were sucrose, sodium chloride, citric acid, caffeine, monosodium glutamate and iron (II) sulfate heptahydrate and the results of the two methods were compared. We found that the threshold values calculated by method ASTM-679 was within the range of concentrations identified with the scales method.