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51.
These activities allow students to investigate behavioral responses of the large Milkweed bug, Oncopeltus fasciatus, and the mealworm, Tenebrio molitor or Tenebrio obscurus, to external stimuli of light, color, and temperature. During the activities, students formulate hypotheses to research questions presented. They also observe insects for a period of time, record observations, analyze the data, and draw conclusions. Important outcomes include experience with critical and analytical thinking and appreciation for the process of science as well as the biology of living things. The activities described herein are appropriate for upper elementary grades, middle school, and high school biology classes.  相似文献   
52.
Behavioral responses of the predatory stink bug Eocanthecona furcellata (Wolff) (Heteroptera: Pentatomidae) towards Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) larvae were observed in olfactometers. In single-and dual-tube olfactometers, adult bugs were observed to approach and stretch their proboscis toward the odor source. These types of behavior were also observed toward the control odor source in the dual-tube olfactometer. However, the frequency of these phases toward the control odor was significantly lower than that toward the odors from intact or dead larvae. The solvent extracts of larvae elicited these similar behavioral phases significantly more frequently and for significantly longer duration than the control. In a linear track olfactometer, E. furcellata nymphs were observed to be attracted to the fraction eluted with hexane from silica gel chromatography but proboscis-protruding behavior was not observed. The other fraction, 15%-ether-in-hexane from silica gel chromatography, elicited the proboscis-protruding behavior by a simple behavioral assay using a Pasteur pipette. These findings therefore indicate the presence of at least two different chemical cues in prey location.  相似文献   
53.
GOING FURTHER INTO LATE MESOZOIC MESOLYGAEIDS (HETEROPTERA, INSECTA)   总被引:1,自引:0,他引:1  
A large collection of fossil insects has recently been recovered from the Late Mesozoic nonmarine sediments throughout East Asia, with many specimens regarded as the mesolygaeids, representing a new family Mesolygaeidae of Heteroptera. As Lycoptera Muller and Eosestheria Chen, Mesolygaeus Ping is the common genus of the Jehol fauna Since some of them are geographically widespread and can be easily collected, they are significant to stratigraphic divisions and correlations in East Asia.  相似文献   
54.
Since its discovery in Florida in 2003, the weeping fig thrips, Gynaikothrips uzeli Zimmerman has spread rapidly throughout the southeastern United States in shipments of ornamental Ficus benjamina L. Concurrently, there have been reports of an invasive anthocorid, Montandoniola confusa (=moraguesi) Streito and Matocq sp. nov., widely associated with G. uzeli populations in landscape plantings of ornamental Ficus spp. We evaluated M. confusa and a commercially available anthocorid, Orius insidiosus Say, as biological control agents of G. uzeli. Prey preference studies revealed that eggs were the numerically preferred host stage for both predator species (representing 92% and 94% of all prey taken in ‘no choice’ and ‘choice’ tests, respectively). Females of both predator species consumed significantly more eggs than males (83–91 versus 25–35 per 48 h period, respectively), and (in the absence of eggs) also more larvae (4.1–5.5 versus 2.1–2.5). Fecundity of M. confusa was significantly higher than for O. insidious, 10.6 ± 1.5 eggs per 48 h versus 5.0 ± 1.4, respectively. Greenhouse tests on heavily infested F. benjamina revealed that M. confusa was a highly effective predator of G. uzeli. Evaluations with three F. benjamina cultivars showed that M. confusa reproduced throughout the year and reduced thrips populations ⩾95% and leaf galls by up to 77% within 5 weeks. By contrast O. insidiosus did not establish or significantly reduce populations of G. uzeli inside leaf galls. Methods to monitor and protect M. confusa in urban landscapes are discussed.  相似文献   
55.
Environmental fluctuations can influence invertebrate population dynamics over large spatial scales, and effects of climate change are of particular importance in understanding phenology. In this study, we tested whether changing climate patterns could increase voltinism and emergence synchrony in Stenotus rubrovittatus and drive the mirid bug’s expansion into currently uninhabited areas of Japan. This expansion could have potentially serious economic consequences for the rice industry. We modelled development of S. rubrovittatus in the field applying the effective accumulated temperature model to calculate the theoretical number of generations and the egg hatching dates from 2003 to 2012 based on a high-resolution, daily weather database. We then performed a regional analysis to assess the relationship between population dynamics and range expansion across the study region and also included a local analysis to evaluate how population parameters affect the presence of S. rubrovittatus at local sites in each year. Results showed that distribution expanded with a relative increase in voltinism and with synchrony of egg hatching date. Moreover, we showed that increased voltinism in the previous year positively influenced local population occurrence. This positive effect suggests that the species’ distribution range expands through increased reproduction at both the regional and local scale. Climate-mediated population dynamics play a significant role in range expansion of the mirid bug.  相似文献   
56.
We compared the biological traits of insecticide resistant and susceptible field populations of tea mosquito bug Helopeltis theivora Waterhouse. The insecticide resistant population of the conventional Tea Estate “Chuapara” of the Dooars, Jalpaiguri, differed significantly from the susceptible strain of the organic Tea Estate “Makibari” of Darjeeling. Both these tea plantation areas are located in the northern part of West Bengal, India. Adverse changes in biological and developmental traits were observed mainly in: (i) reduction in oviposition period; (ii) fecundity; and (iii) prolongation of nymphal and total developmental period. However, all other parameters such as pre- and post oviposition periods, egg incubation period, hatchability and adult longevity were not significantly different. These results clearly demonstrated that only certain fitness components in the resistant strains appear to be adaptively changed and lowered.  相似文献   
57.
Piezodorus guildinii (Westwood) (Heteroptera: Pentatomidae), a major pest of soybean in South America, feeds on alternative legume hosts, and four species of Indigofera were tested. Nymphal survival was 88% on I. endecaphylla Jacq. (IE), 15% on I. suffruticosa Mill. (IS), 70% on I. hirsuta L. (IH) and 40% on I. truxilliensis H.B.K. (IT). From stadia 2 through 5, fastest development (22 days) occurred on IE and IT, and the slowest (29 days) on IS. Fresh body weight at emergence was higher for nymphs fed on IE and IT. Adult survival of P. guildinii after 40 days, was greater than 70% on IT and IE, and less than 20% on IS. Females oviposited on all Indigofera species, but <30% were observed to lay eggs on IS. Body weight gain during the first week was greater for adults feeding on IE and IH. Insects lost weight on IS; at the end of day 15 no differences in percent change in body weight, among the food plants tested, were observed. Field surveys conducted on IT and IS, the two most abundant species in northern Paraná, indicated a greater number of nymphs, adults, and egg masses on the former host. On both hosts P. guildinii was more abundant during April/May, after soybean harvest, suggesting movement of the populations from soybean to Indigofera.  相似文献   
58.
The swallow bug (Oeciacus vicarius) is the only known vector for Buggy Creek virus (BCRV), an alphavirus that circulates in cliff swallows (Petrochelidon pyrrhonota) and house sparrows (Passer domesticus) in North America. We discovered ants (Crematogaster lineolata and Formica spp.) preying on swallow bugs at cliff swallow colonies in western Nebraska, U.S.A. Ants reduced the numbers of visible bugs on active swallow nests by 74‐90%, relative to nests in the same colony without ants. Ant predation on bugs had no effect on the reproductive success of cliff swallows inhabiting the nests where ants foraged. Ants represent an effective and presumably benign way of controlling swallow bugs at nests in some colonies. They may constitute an alternative to insecticide use at sites where ecologists wish to remove the effects of swallow bugs on cliff swallows or house sparrows. By reducing bug numbers, ant presence may also lessen BCRV transmission at the spatial foci (bird colony sites) where epizootics occur. The effect of ants on swallow bugs should be accounted for in studying variation among sites in vector abundance.  相似文献   
59.
Ongoing studies by our group showed that the outcome of the intrinsic competition between two solitary egg parasitoids, Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), is dominated by O. telenomicida. In this article we investigated the role played by the ovipositing O. telenomicida female in the suppression of a T. basalis competitor. Laboratory experiments were conducted by allowing an O. telenomicida female to puncture the eggs of Nezara viridula (L.) (Heteroptera: Pentatomidae) with her ovipositor (= no oviposition) or to parasitize them. The results show that O. telenomicida relies on some physiological mechanisms to mediate its interspecific intrinsic competition with T. basalis. In fact, the emergence of T. basalis was strongly reduced in host eggs that were parasitized either before or after being punctured by O. telenomicida at fixed time intervals (5, 15, 30, or 45 h). The low percentage of emergence of T. basalis (ranging from approximately 4–20%) was a consequence of the delay and growth rate reduction of larval development. Furthermore, the percentage of eclosion of N. viridula nymphs was negatively affected by the O. telenomicida female’s punctures (96% from healthy host eggs, 4% from punctured host eggs). Host eggs punctured or oviposited in by O. telenomicida showed alterations in the ooplasm including some melanized‐like areas near the hole made with the ovipositor; such alterations indicate that the adult parasitoid releases substances that affect the host eggs survival. These results suggest that the O. telenomicida female influences both the physiological interspecific parasitoid‐parasitoid interaction, as well as the host‐parasitoid interaction, providing, for the first time in egg parasitoids, evidence that physiological suppression of some competitive egg parasitoids is mediated by the ovipositing female.  相似文献   
60.
The tarnished plant bug, Lygus hesperus Knight, is a pest that causes considerable economic losses to vegetables, cotton, canola, and alfalfa. Detailed knowledge of its digestive physiology will provide new opportunities for a sustainable pest management approach to control this insect. Little is known about the different protease class contributions to the overall digestion of a specific protein. To this end, the proteolytic activities in female adult L. hesperus salivary gland and midgut homogenates were quantified over a range of pH's and time points, and the contribution of different classes of proteases to the degradation of FITC-casein was determined. In the salivary gland, serine proteases were the predominant class responsible for caseinolytic activity, with the rate of activity increasing with increasing pH. In contrast, both aspartic and serine proteases contributed to caseinolytic activity in the midgut. Aspartic protease activity predominated at pH 5.0 and occurred immediately after incubation, whereas serine protease activity predominated at pH 7.5 after a 9h delay and was resistant to aprotinin. The salivary serine proteases were distinctly different from midgut serine proteases, based on the tissue-specific differential susceptibility to aprotinin and differing pH optima. Collectively, the caseinolytic activities complement one another, expanding the location and pH range over which digestion can occur.  相似文献   
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