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101.
Design and selection of trap color for capture of the tea leafhopper,Empoasca vitis,by orthogonal optimization 总被引:2,自引:0,他引:2
Lei Bian Xiao‐Ling Sun Zong‐Xiu Luo Zheng‐Qun Zhang Zong‐Mao Chen 《Entomologia Experimentalis et Applicata》2014,151(3):247-258
The tea leafhopper, Empoasca vitis (Göthe) (Hemiptera: Cicadellidae), is a major pest of the tea plant, Camellia sinensis (L.) O. Kuntze (Theaceae). In this study, the RGB color model was used to describe the colors of sticky traps. The most effective color for attraction of E. vitis was investigated by orthogonal optimization. The selected color was verified in tea gardens and the most effective height for positioning of color sticky traps for capturing tea leafhoppers was investigated. After the determination of the effect of the three color parameters and their interactions by orthogonal optimization, the color gold (RGB: 255, 215, 0) was selected as the most effective color to trap tea leafhoppers. In tea gardens, more leafhoppers were captured using gold sticky traps (RGB: 226, 204, 4) than using commercially available yellow sticky traps. The most effective height of gold sticky traps for trapping leafhoppers was 40–60 cm above the tea canopy. Few lady beetles were captured at this height. We conclude that the orthogonal optimization method is a convenient and efficient method to screen digitally generated colors for attracting and trapping of pests. 相似文献
102.
Monarch butterflies, Danaus plexippus L. (Lepidoptera: Nymphalidae), have a multiple brood migration in the spring as they move between their overwintering grounds and summer breeding grounds. In Oklahoma, USA, monarchs produce at least one generation in the spring, which develops and continues the northward migration, leaving Oklahoma without a breeding population during the hot summer months. Female monarchs leave the overwintering grounds prior to males, but it is not clear whether females re‐colonize areas along the migration route prior to, or at the same time as males. Male‐to‐female ratios are 1:1 at emergence, but studies have identified a male‐biased sex ratio in the field. Both males and females are susceptible to infection by the obligate protozoan parasite, Ophryocystis elektroscirrha McLaughlin & Myers (OE), which reduces flight abilities and life spans of infected individuals. We examine sex ratios during the spring migration through Oklahoma and whether sex ratios or OE infection estimates vary with capture technique (active or passive). Our data suggest populations are male‐biased during the 1st week of spring migration in Oklahoma, but shift to female‐biased by the 3rd week in both cool and warm springs. Therefore, males may leave southern areas prior to females or migrate longer distances per day. Active sampling (i.e., netting) did not bias sex compared to passive sampling (i.e., sticky traps). Significantly fewer OE‐carrying monarchs (with two or more spores) were captured via netting than by sticky traps which may be caused by sticky trap glue affecting tape sampling effectiveness, but there was no difference in the number of heavily infected individuals (more than 100 spores). Therefore, data from netted monarchs may underestimate OE infection rates within populations. 相似文献
103.
Jerry F. Tien Neil T. Umbreit Alex Zelter Michael Riffle Michael R. Hoopmann Richard S. Johnson Bryan R. Fonslow John R. Yates III Michael J. MacCoss Robert L. Moritz Charles L. Asbury Trisha N. Davis 《Genetics》2014,198(4):1483-1493
Accurate transmission of genetic material relies on the coupling of chromosomes to spindle microtubules by kinetochores. These linkages are regulated by the conserved Aurora B/Ipl1 kinase to ensure that sister chromatids are properly attached to spindle microtubules. Kinetochore–microtubule attachments require the essential Ndc80 complex, which contains two globular ends linked by large coiled-coil domains. In this study, we isolated a novel ndc80 mutant in Saccharomyces cerevisiae that contains mutations in the coiled-coil domain. This ndc80 mutant accumulates erroneous kinetochore–microtubule attachments, resulting in misalignment of kinetochores on the mitotic spindle. Genetic analyses with suppressors of the ndc80 mutant and in vitro cross-linking experiments suggest that the kinetochore misalignment in vivo stems from a defect in the ability of the Ndc80 complex to stably fold at a hinge in the coiled coil. Previous studies proposed that the Ndc80 complex can exist in multiple conformations: elongated during metaphase and bent during anaphase. However, the distinct functions of individual conformations in vivo are unknown. Here, our analysis revealed a tightly folded conformation of the Ndc80 complex that is likely required early in mitosis. This conformation is mediated by a direct, intracomplex interaction and involves a greater degree of folding than the bent form of the complex at anaphase. Furthermore, our results suggest that this conformation is functionally important in vivo for efficient error correction by Aurora B/Ipl1 and, consequently, to ensure proper kinetochore alignment early in mitosis. 相似文献
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105.
Using Optics to Measure Biological Forces and Mechanics 总被引:1,自引:0,他引:1
Scot C. Kuo 《Traffic (Copenhagen, Denmark)》2001,2(11):757-763
Spanning all size levels, regulating biological forces and transport are fundamental life processes. Used by various investigators over the last dozen years, optical techniques offer unique advantages for studying biological forces. The most mature of these techniques, optical tweezers, or the single-beam optical trap, is commercially available and is used by numerous investigators. Although technical innovations have improved the versatility of optical tweezers, simple optical tweezers continue to provide insights into cell biology. Two new, promising optical technologies, laser-tracking microrheology and the optical stretcher, allow mechanical measurements that are not possible with optical tweezers. Here, I review these various optical technologies and their roles in understanding mechanical forces in cell biology. 相似文献
106.
Evaluation of traps of six different designs to capture pine sawyer beetles (Coleoptera: Cerambycidae) 总被引:1,自引:0,他引:1
1 Sawyer beetles (Coleoptera: Cerambycidae) and metallic wood‐boring beetles (Coleoptera: Buprestidae) attack recently killed or felled trees. They are attracted to potential hosts by volatiles and possibly by visual cues. We examined traps of six different designs to determine the role of silhouette and shape in the capture of pine sawyer beetles, Monochamus L. 2 Traps with a round black cylinder, a single vane (clear or black), or cross vanes (clear or black) all mounted above a pan were compared to an open pan. Each pan contained soapy water to retain insects. 3 Traps with a black silhouette were significantly more effective in capturing male and female Monochamus scutellatus (Say) than traps with or without clear vanes. For both sexes of M. mutator LeConte, pan traps were as effective as traps with a black silhouette. Silhouette was not important for the capture of male and female M. notatus (Drury). Trap catches for the six trap types were not significantly different for male Buprestis maculativentris Say. 4 A pan trap with a black silhouette is recommended for general use in capturing wood‐boring cerambycids and buprestids. 相似文献
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109.
为了探究科研调查中不同昆虫采集方法的采集效率差异,在北京珍珠泉乡不同的生境类型中,采用样线法、马氏网法、灯诱法、陷阱法(糖醋液)4种采集方法进行昆虫采集,按生境类型对不同采集方法采集的昆虫进行统计分析.在实验中共采集昆虫3996头,隶属12目87科,其中在昆虫种类数量上,鳞翅目最多,其次是半翅目和鞘翅目;在数量上,半翅目昆虫数量最多,依次是双翅目和鳞翅目.样线法共采集到昆虫61科72种、灯诱法共采集到45科95种、马氏网法共采集到39科41种、陷阱法共采集到14科25种.在调查中,不同方法在不同生境采集昆虫种类数多存在显著差异(P<0.05).不同的采集方式间除马氏网和样线法采集昆虫的种类相似度为中等不相似(q=0.436),其他方法间均为极不相似.采用不同的采集方式可以采集到更多的昆虫种类.马氏网法是最优选的采集方式,马氏网采集昆虫最方便,节省人力;样线法采集的效果最稳定;灯诱法的采集效果好,但是应用较为复杂;糖醋液陷阱法采集昆虫效率对比其他三种方法,既不能采集到大量昆虫也没有采集到特定种昆虫,如无特别需求可以考虑减少或者放弃使用. 相似文献
110.
Yoamel MilinGarcía Robert Young Mary Madden Erin BullasAppleton Robert H. Hanner 《Ecology and evolution》2021,11(5):1999
Environmental DNA (eDNA) metabarcoding has revolutionized biodiversity monitoring and invasive pest biosurveillance programs. The introduction of insect pests considered invasive alien species (IAS) into a non‐native range poses a threat to native plant health. The early detection of IAS can allow for prompt actions by regulating authorities, thereby mitigating their impacts. In the present study, we optimized and validated a fast and cost‐effective eDNA metabarcoding protocol for biosurveillance of IAS and characterization of insect and microorganism diversity. Forty‐eight traps were placed, following the CFIA''s annual forest insect trapping survey, at four locations in southern Ontario that are high risk for forest IAS. We collected insects and eDNA samples using Lindgren funnel traps that contained a saturated salt (NaCl) solution in the collection jar. Using cytochrome c oxidase I (COI) as a molecular marker, a modified Illumina protocol effectively identified 2,535 Barcode Index Numbers (BINs). BINs were distributed among 57 Orders and 304 Families, with the vast majority being arthropods. Two IAS (Agrilus planipennis and Lymantria dispar) are regulated by the Canadian Food Inspection Agency (CFIA) as plant health pests, are known to occur in the study area, and were identified through eDNA in collected traps. Similarly, using 16S ribosomal RNA and nuclear ribosomal internal transcribed spacer (ITS), five bacterial and three fungal genera, which contain species of regulatory concern across several Canadian jurisdictions, were recovered from all sampling locations. Our study results reaffirm the effectiveness and importance of integrating eDNA metabarcoding as part of identification protocols in biosurveillance programs. 相似文献