• Title/Summary/Keyword: Predators

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Susceptibility of the Predatory Mite, Neoseiulus californicus (Acari: Phytoseiidae) to Acaricides (사막이리응애의 살응애제에 대한 감수성)

  • Lee, Sung Min;Kim, Sang Soo
    • The Korean Journal of Pesticide Science
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    • v.19 no.4
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    • pp.418-423
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    • 2015
  • Effects of 9 acaricides to the predatory mite, Neoseiulus californicus were evaluated. Seven of the acaricides tested, cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron and cyflumetofen exhibited low toxicity to adult females and nymphs of N. californicus and had little effect on the reproduction and eclosion of eggs deposited by treated predators. Moreover, hatch percentage of N. californicus eggs was unaffected by exposure to these seven acaricides. Etoxazole did not significantly affect the survival and reproduction of adult female predators but caused very low eclosion in eggs laid by treated females and high egg mortality. Pyraclofos was extremely toxic to adult female predators and caused 100% mortality. Adult female predators survived on a diet of spider mites treated with cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron and cyflumetofen and their fecundity was not substantially affected. Based on the results, cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron and cyflumetofen are appeared to be promising candidates for use in integrated mite management program where N. californicus is the major natural enemy.

Biological Control of Pests of Non-Mulberry Silkworms and Its Host Plants in India

  • Singh, R.N.;Maheshwari, M.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.4 no.2
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    • pp.83-91
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    • 2002
  • The protection of silkworm and its host plants from various kinds of pests parasite and predator is a chronic problem in sericulture. Silkworms and its primary food plants are heavily damaged by large number of pest. The major pests of primary tasar food plants (Terminalia arjuna and Terminalia tomentosa) are the gall insect (Trioza fletcheri minor). Various species of aphids (Eutrichosiphum sp.) have been recorded to damage oak tasar food plants whereas muga silkworm host plants (Machilus bombycina and Litsaea polyantha) are generally attacked by stem bores (Zeuzera multistrigata). Castor (Ricinus communis) is one of the primary host plant of eri silkworm and extensive damage is caused by the castor white fly (Trialeurodes ricini). Insects pests are major enemies of silkworms. Parasites (Blepharipa zebina, Exorista bombycis, Apateles glomeratus), predators (Canthecona furcellata, Sycanus collaris, Hierodulla bipapilla), wasps (Vespa orientalix) and ants (Oecophylla smargdina) continues to cause damage to silk industry. It is estimated that the losses due to parasites and predators are to an extent of 15-20 percent and varies from crop to crop. The complexities in the behaviour and life cycle of pest population existing in semi ecosystem warrant a special attention for their effective management specially in changing scenario for our modern sericulture. Though use of synthetic insecticides has provided us with effective control of almost all major pests and predators, yet their undesirable side effects limit their continued use. Biological control is one of the most important method which can be used to control the pests, parasites and predators population in sericulture. Various potential parasitoids, which can be utilized as an agent of biological control in sericulture have been screened. The natural enemies of the uzi fly (E. bombycis and B. zebina ) are already present in the nature. Nesolynx thymus, Trichria sp., Splangia endius, Dirhinus sp., Trichopria sp., Trichomalopsis apanteloctena and Pediobius sp. are the major parasitoids effective against uzi fly pupa. The scelionid Psix striaticeps and Trissolcus sp. are the Potential egg Parasitoids against stink bug (Canthecona furcellata). Various other native natural potential parasitoids have been screened and suitable strategies have been developed to check the population of pest insect in sericulture.

Behavioral Function of the Anomalous Song in the Bush Warbler, Cettia diphone

  • Park, Shi-Ryong;Cheong, Seok-Wan;Chung, Hoon
    • Animal cells and systems
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    • v.8 no.2
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    • pp.89-95
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    • 2004
  • The bush warblers (Cettia diphone) have been recognized to possess two types of songs: a normal song that plays roles in attracting mate and territorial defense, and an anomalous song. The present study suggests that the anomalous song functions as an alarm signal as well as other unknown signals. Field observations and playback experiments on the anomalous song of bush warbler were conducted in order to investigate the contextual information that occurred between sender and receiver. In the field observation, the males frequently emitted anomalous songs to potential predators. The males responded with an anomalous song to stuffed potential predators. The distance from where the anomalous song occurs to the stimulating source varied depending upon the kinds of stimulus. The males of bush warbler possibly show different responses to the anomalous song depending on the level of danger. When the anomalous song was played back to terrestrial males and females, no distinctive behavior was observed. The anomalous song may be sung to defend the territory against predators or to distract invaders from the nest and female because the male and female behaviors were related with the anomalous song and its phonetic characteristics.

Fauna of Macroinvertebrates and Composition of Functional Feeding Groups about the Aquatic Insects to Microhabitats from the Geum River, Korea

  • Park, Young-Jun;Cho, Young-Ho;Han, Yong-Gu;Oh, Hong-Sik;Kwon, Oh-Seok;Nam, Sang-Ho
    • Journal of Ecology and Environment
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    • v.29 no.5
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    • pp.415-424
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    • 2006
  • The main objective of this study is to find out the fauna of macroinvertebrate and composition of functional feeding groups about the aquatic insects to microhabitat from the Geum River, Korea. This study is based on investigations of the main channel of Geum River, Korea which is upstream of Daecheong Dam, and carried out in the spring and autumn of 2004. Collections from all the sites were 39,532 individuals, 130 species, 54 families, 16 orders, 7 classes, and 4 phyla of macroinvertebrates. Aquatic insects were composed of 90.76% (118 species) and 98.88% (39,088 individuals) of all the identified species. Among the microhabitats, the riffles were collected 26,293 individuals and 92 species, and the runs were collected 12,329 individuals and 89 species. Finally, the pools were collected 494 individuals and 41 species. In this survey, the proportions of functional feeding groups of aquatic insects were as follows (percent of identified): predators 37.65%, gathering-collectors 23.53%, scrapers 16.47%, filtering-collectors 11.76%, shredders 9.41% and plant-piercers 1.18%. Also, the functional feeding groups were sorted according to microhabitat, in the riffles 30.65% were predators and 29.03% were gathering-collectors; in the run 30.3% were predators, and 28.79% were gathering-collectors; while in the pools 36.67% were predators, and 30.0% were gathering-collectors. In all microhabitats, gathering collectors and predators were predominant, because most of the survey sites are in the midstream. Also, the scrapers were shown more frequently in the riffle (17.74%) and run (18.18 %) than pool (13.13%), the filtering-collectors were shown more frequently in the riffle (14.52%) and the run (12.12%) than the pool (6.67%), and the plant-piercers (3.33%) were found only in pools. But the shredders weren't a difference in the run (10.61%), the pool (10.0%) and the riffle (8.06%), because of the characteristic. Microhabitats (riffle and run) are much alike in composition ratio of functional feeding groups and pool was very lower out of composition ratio in microhabitats. But riffle is very important than run, because most of individual occur in streams. Besides, pool was diverse to composition ratios, considering the number of individuals.

Growth and Reproductive Biology of the Freshwater Shrimp Exopalaemon modestus(Decapoda: Palaemonidae) in A Lake of Korea

  • Oh, Chul-Woong;Suh, Hae-Lip;Ma, Chae-Woo;Jeong, In-Ju;Kim, Jang-Young
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.10a
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    • pp.313-314
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    • 2001
  • The palaemonid shrimp Exopazaemon modestus inhabits the freshwater of the Indo-West Pacific, Siberia, Manchuira, Korea, China, Taiwan (Holthuis, 1980) and is abundant in the fresh water areas of southwest of Korea. Palaemonid shrimps are adapted to a variety of habitats in freshwater, brackish and marine environments. They play important role in the ecosystem of fresh, brackish and marine waters, acting as predators feeding on algae, detritus, crustaceans and meiofauna (Bell and Coull, 1978) and in turn, as preys for fishes and other predators (Anderson, 1985). (omitted)

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Feeding by common heterotrophic protist predators on seven Prorocentrum species

  • You, Ji Hyun;Jeong, Hae Jin;Kang, Hee Chang;Ok, Jin Hee;Park, Sang Ah;Lim, An Suk
    • ALGAE
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    • v.35 no.1
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    • pp.61-78
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    • 2020
  • Species belonging to the dinoflagellate genus Prorocentrum are known to cause red tides or harmful algal blooms. To understand the dynamics of a Prorocentrum sp., its growth and mortality due to predation need to be assessed. However, there are only a few Prorocentrum spp. for which heterotrophic protist predators have been reported. We explored feeding by the common heterotrophic dinoflagellates Gyrodinium dominans, Oxyrrhis marina, Pfiesteria piscicida, Oblea rotunda, and Polykrikos kofoidii and the naked ciliate Strombidinopsis sp. (approx. 90 ㎛ cell length) on the planktonic species Prorocentrum triestinum, P. cordatum, P. donghaiense, P. rhathymum, and P. micans as well as the benthic species P. lima and P. hoffmannianum. All heterotrophic protists tested were able to feed on the planktonic prey species. However, O. marina and O. rotunda did not feed on P. lima and P. hoffmannianum, while G. dominans, P. kofoidii, and Strombidinopsis sp. did. The growth and ingestion rates of G. dominans and P. kofoidii on one of the seven Prorocentrum spp. were significantly different from those on other prey species. G. dominans showed the top three highest growth rates when it fed on P. triestinum, P. cordatum, and P. donghaiense, however, P. kofoidii had negative growth rates when fed on these three prey species. In contrast, P. kofoidii had a positive growth rate only when fed on P. hoffmannianum. This differential feeding on Prorocentrum spp. between G. dominans and P. kofoidii may provide different ecological niches and reduce competition between these two common heterotrophic protist predators.

An Integrated Approach in the Pest Management in Sericulture

  • Singh, R.N.;Saratchandra, Beera
    • International Journal of Industrial Entomology and Biomaterials
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    • v.5 no.2
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    • pp.141-151
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    • 2002
  • The success of sericulture industry in India is mainly attributed to the well-planned annual sericultural activity and the systematic implementation of pest preventive and control measures. The insect spectrum of silkworm and its food plants is complex and plays a major role in limiting the production of silk. Insects cause extensive damage to plant whereas predators and parasites either kill the silkworm larvae or force them to spin flimsy cocoons. Unilateral control measure against this pest is mainly based on the use of synthetic organic insecticides. Though these approaches initially paid rich dividends, the undesirable consequences soon surfaced. Insecticide induced resurgence of gall midges, leafhopper, leaf roller, secondary pest out breaks and development of pest biotypes has led to realization of Integrated Pest Management in sericulture. Various components of IPM, viz. Host plant resistance, cultural practices, biological control, chemical control and integrating them at various technological levels have been studied. Sources of host plant resistance have been identified for some of the major insect pests. High yielding mulberry variety has been propagated and their resistances towards major pests have been recorded. Cultural practices like pruning, pollarding, judicious use of nitrogen, optimum spacing and weed management have preyed to be the powerful tools in containing pests. Natural control over the pest population build- up exerted by the wide range of parasitoids, predators and pathogens has been well documented with identification of natural enemies and studies on their potential. Augmentation, through inoculation or inundative releases of parasitic arthropods, is the most direct way of increasing the numbers of these beneficials in sericulture.

Integration of Optimality, Neural Networks, and Physiology for Field Studies of the Evolution of Visually-elicited Escape Behaviors of Orthoptera: A Minireview and Prospects

  • Shin, Hong-Sup;Jablonski, Piotr G.
    • Journal of Ecology and Environment
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    • v.31 no.2
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    • pp.89-95
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    • 2008
  • Sensing the approach of a predator is critical to the survival of prey, especially when the prey has no choice but to escape at a precisely timed moment. Escape behavior has been approached from both proximate and ultimate perspectives. On the proximate level, empirical research about electrophysiological mechanisms for detecting predators has focused on vision, an important modality that helps prey to sense approaching danger. Studies of looming-sensitive neurons in locusts are a good example of how the selective sensitivity of nervous systems towards specific targets, especially approaching objects, has been understood and realistically modeled in software and robotic systems. On the ultimate level, general optimality models have provided an evolutionary framework by considering costs and benefits of visually elicited escape responses. A recent paper showed how neural network models can be used to understand the evolution of visually mediated antipredatory behaviors. We discuss this new trend towards integration of these relatively disparate approaches, the proximate and the ultimate perspectives, for understanding of the evolution of behavior of predators and prey. Focusing on one of the best-studied escape pathway models, the Orthopteran LGMD/DCMD pathway, we discuss how ultimate-level optimality modeling can be integrated with proximate-level studies of escape behaviors in animals.

Population Dynamics Pattern of Green Peach Aphid (Homoptera: Aphididae) and Its Predator Complex in a Potato System

  • Ro, Tae-Ho;Garrell E. Long
    • Animal cells and systems
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    • v.2 no.2
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    • pp.217-222
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    • 1998
  • Green peach aphid, Myzus persicae(Sulzer) (Homoptera: Aphididae), interacts with many predatory insects in potato fields during the summer. The concept of the predator complex associated with green peach aphids was applied to explain the interactions between the aphid and its predators. The predator power of the predator complex was determined by two factors: the number of predators and the relative feeding capacity. The dynamics of the green peach aphid population was expressed by the number of individuals while the predator power was used to characterize the predator complex. Cumulative degree-days for green peach aphids were used as a time scale to analyze phonology and dynamics patterns of the aphid and its predator complex. The patterns of population changes in aphids were similar during the period of study(1993-1995) although the highest density of aphids fluctuated significantly from year to year. However, the predator power appeared more stable than the green peach aphid population over the three year period. The results indicated that the predator complex plays an important role to suppress the aphid populations during the latter part of the season and that the applications of control measures for green peach aphids in between the initiation and the peak timing of aphid populations are critical to minimize the damage on potatoes.

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Influences of Disturbance Intensity on Community Structure, Species Richness and Abundance of Arthropod Predators (Araneae, Carabidae, Staphylinidae, and Formicidae) in Burned-pine Forest (산불지에서 절지동물 포식자(거미목, 딱정벌레과, 반날개과와 개미과)의 군집구조, 종풍부도 및 풍부도에 대한 교란강도의 영향)

  • Lee, Cheol Min;Kwon, Tae-Sung;Park, Young Kyu;Kim, Byung-Woo
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.488-500
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    • 2012
  • The present study was carried out to evaluate arthropod predators (Araneae, Carabidae, Staphylinidae, and Formicidae) as bioindicator for forest disturbance. We selected 12 study sites according to disturbance intensities caused by fire intensity and recovery methods at Goseong, Gangneung, and Samcheok in Gangwondo. Intensities of disturbance were characterized as follows: 0 (no fire), 1 (surface fire), 2 (crown fire), and 3 (crown fire followed by reforestation). Arthropod predators were captured using pitfall trap. Species richness and abundance of Araneae, Carabidae, Staphylinidae, and Formicidae were not different along disturbance intensities. However, species richness and abundance of grassland ants significantly increased in higher disturbance intensities. Abundance of grassland ants such as Formica japonica and Camponotus japonicas linearly decreased along litter depth. Furthermore, ant communities were clustered along disturbance intensities. In a one-time survey, ants may be most useful as bioindicator for forest disturbance among the four predator taxa, because ants actively forage for long seasons.