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31.
32.
A field experiment was conducted using Ceranock bait station, "attract and kill" system to combat Mediterranean fruit fly, Ceratitis capitata, in apricot orchards, Central of lraq during the 2013 field season. Control program was implemented in three orchards of mixed apricot varieties. Ceranock traps were hung in each tree of two separate orchards. Delta and McPhail traps were used to monitor Medfly population density in each treated and control orchards. Results indicated that Medfly activity in apricot orchards started during the last week of April coincided with the beginning of maturity for fruits of early varieties. The total of trapped insects in monitoring traps after one week of Ceranock application were 0, 1 and 31 adults for the 1st, 2nd and the control orchards, respectively. Three weeks later and on, the number of trapped adults started to increase dramatically. At the end of apricot season and after 45 days of Ceranock trap application, the number of trapped insects in monitoring traps reached 110, 111 and 2,349 adults/week, respectively, for the 1st, 2nd and 3rd orchard. The use of Ceranock traps reduced Medfly population density by 86%-97%. The percentage of fruit injuries in early maturing varieties were 0.75%, 1% and 34% for the 1st, 2nd and control orchards, respectively. While, late varieties were 2% and 3% for 1st and 2nd orchards, and 69% for the control. The percentage of reduction in fruit damages reached to 95% and 97%, respectively in the 1st and 2nd orchard. The results of this study demonstrate clearly the efficacy of Ceranock bait station, "attract and kill" system as a control measure for Medfly in apricot orchards. 相似文献
33.
A. van Harten 《Potato Research》1983,26(1):1-15
Summary In the Netherlands early haulm destruction is the main method of preventing excessive spread of virus diseases in seed potato
crops. When potato leaf roll virus was the principal problem, the time of haulm destruction was determined by the flight ofMyzus persicae (Sulzer), studied with the aid of Moericke yellow water traps. As potato virus YN became a problem and other aphid species interfered, the interpretation of aphid flights became difficult.
An attempt is made to quantify total aphid flight activity in terms of risk to the crop. By attributing relative efficiency
factors to 9 vector species and considering their flights as recorded with suction traps, values of vector-pressure are obtained
that correlate well with weekly infection of bait plants. If accumulated vector pressures are compared with the flights ofM. persicae as recorded with Moericke traps during 1970–1979, it appears that during 6 of these years the critical periods of both systems
coincide. However, in 1974 and 1976 much potential vector threat occurred before the start of the flight ofM. persicae. Suggestions are made as to how to apply the method in practice.
A semi-popular account of this paper has appeared in Dutch inGewasbescherming 12 (1981) 57–71. 相似文献
34.
35.
Green roofs are a promising tool to return nature to cities and mitigate biodiversity loss brought about by urbanization. Yet, we lack basic information on how green roofs contribute to biodiversity and how their placement in the urban landscape affects different taxa and community composition. We studied the effects of local and landscape variables on beetle communities on green roofs. We expected that both local roof characteristics and urban landscape composition shape communities, but that their relative importance depends on species characteristics. Using pitfall traps, we collected beetles during two consecutive years from 17 green roofs in Basel, Switzerland. We evaluated the contribution of six local and six landscape variables to beetle community structure and to the responses of individual species. Communities on the roofs consisted of mobile and open dry-habitat species, with both local and landscape variables playing a role in structuring these communities. At the individual species level, local roof variables were more important than characteristics of the surrounding urban landscape. The most influential factors affecting the abundances of beetle species were vegetation, described as forb and grass cover (mainly positive), and roof age (mainly negative). Therefore, we suggest that the careful planning of green roofs with diverse vegetation is essential to increase their value as habitat for beetles. In addition, while beetle communities on green roofs can be diverse regardless of their placement in the urban landscape, the lack of wingless species indicates the need to increase the connectivity of green roofs to ground level habitats. 相似文献
36.
中性粒细胞是机体先天性免疫系统中的重要组成成分,是外周血中数量最多的免疫细胞,在非特异性免疫中至关重要,是构成机体内抵御微生物入侵的第一道防线。近年来,人们发现中性粒细胞除了经典的通过胞吞作用吞噬病原微生物、释放嗜天青颗粒及产生并分泌抑菌杀菌物质外,还具有抵抗微生物入侵的新机制--中性粒细胞细胞外诱捕网(neutrophil extracellular traps,NETs)。该机制主要通过活性氧和肽酰基精氨酸脱亚氨酶4等影响因子刺激中性粒细胞形成以DNA为骨架的网状结构,内含有多种蛋白酶,能非特异性捕获杀伤病原体,还能在机体某些疾病的产生和发展中起到协同作用。作者就NETs的形成、影响因素及与病原、疾病的相互关系作一概述,为进一步研究中性粒细胞的功能提供依据。 相似文献
37.
38.
中性粒细胞作为机体天然免疫系统的重要组成部分,发挥至关重要的防御病原体感染的作用。中性粒细胞发挥防御作用的机制之一是通过释放中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)捕获并消灭病原体。然而有些病原体已进化出逃避NETs的机制,从而对机体造成持续损伤。此外,NETs的异常状态也会对机体造成一些损伤。近年来,NETs已成为中性粒细胞功能研究的热点,受到了国内外学者的广泛关注。有学者在禽的异嗜性粒细胞中也发现了类似NETs功能的网状结构,并将其命名为异嗜性粒细胞胞外诱捕网(heterophil extracellular traps,HETs)。作者主要对NETs抵御病原体入侵和病原体逃避NETs的机制并引起宿主致病等过程进行综述。 相似文献
39.
40.
In 1992–2002, the flight activity of Adoxophyes orana (AO) was investigated using pheromone traps placed in apple orchards in five localities in Central and Eastern Bohemia. The
cumulative catches of AO were plotted against time expressed as the sum of day-degrees (D°) above 8°C and approximated by
a Richards’ function. This model was constructed using the numbers of AO males caught by pheromone traps from 1992–1998 at
all the localities. The flight of the overwintering generation of AO began when 200 D° had accumulated, culminated at 300
D° and ceased at 430 D°, irrespective of locality. The high predictive ability of the model was validated using data from
one locality for 2001–2003. It was impossible to construct a similar model to predict the flight activity of the summer generation
because its dependence on D° varied greatly between localities and years. 相似文献