نتایج جستجو برای: tobacco beetle

تعداد نتایج: 65301  

2015
J. C. Vandygriff E. M. Hansen B. J. Bentz K. K. Allen G. D. Amman L. A. Rasmussen

Mountain pine beetle, Dendroctonus ponderosae Hopkins, is the most significant mortality agent in pine forests of western North America. Silvicultural treatments that reduce the number of susceptible host trees, alter age and size class distributions, and diversify species composition are considered viable, long-term options for reducing stand susceptibility to mountain pine beetle-caused tree ...

2004
BRIAN J. KOPPER KIER D. KLEPZIG KENNETH F. RAFFA

Efforts to describe the complex relationships between bark beetles and the ophiostomatoid (stain) fungi they transport have largely resulted in a dichotomous classiÞcation. These symbioses have been viewed as either mutualistic (i.e., fungi help bark beetles colonize living trees by overcoming tree defenses or by providing nutrients after colonization in return for transport to a host) or antag...

2007
Nora Underwood Mark D. Rausher D. RAUSHER

To determine whether plant genotype can affect long-term herbivore population dynamics, we used a density manipulation experiment to compare the dynamics of Mexican bean beetle populations living on four genotypes of soybeans. Five densities of beetle populations were created on each plant genotype. Each combination of density and genotype was replicated four times, yielding 80 experimental bee...

2016
Barbara J. Bentz Jacob P. Duncan James A. Powell

Future forests are being shaped bychanging climate and disturbances. Climate change is causing large-scale forest declines globally, in addition to distributional shifts of many tree species. Because environmental cues dictate insect seasonality and population success, climate change is also influencing tree-killing bark beetles. The mountain pine beetle, Dendroctonus ponderosae, is a major dis...

Journal: :Ecological applications : a publication of the Ecological Society of America 2016
D W Goodsman D Koch C Whitehouse M L Evenden B J Cooke M A Lewis

Most species that are negatively impacted when their densities are low aggregate to minimize this effect. Aggregation has the potential to change how Allee effects are expressed at the population level. We studied the interplay between aggregation and Allee effects in the mountain pine beetle (Dendroctonus ponderosae Hopkins), an irruptive bark beetle that aggregates to overcome tree defenses. ...

Journal: :Journal of economic entomology 2005
G Christopher Cutler Jeffrey H Tolman Cynthia D Scott-Dupree C Ronald Harris

Novaluron (Rimon 10 EC), a novel insect growth regulator, could play an important role in future management programs for Colorado potato beetle, Leptinotarsa decemlineata (Say). Studies were conducted to determine the potential of Colorado potato beetle to develop resistance to novaluron before its widespread use in Colorado potato beetle management. Second instars of an imidacloprid-resistant ...

Journal: :iranian journal of pharmaceutical research 0
f fathiazad a delazar r amiri sd sarker

the potential of tobacco waste as a viable source of medicinally important flavonoids like rutin has been investigated. three flavonoids, apigenin, quercetin and rutin, have been isolated from waste tobacco leaves, and their identities have been confirmed by uv-visible, 1h-nmr and 13c-nmr spectroscopy. by using analytical hplc, the amount of rutin present in the tobacco leaves, before and after...

Journal: :Current Biology 2008
Florian Maderspacher

Beetles are reckoned to make up about one quarter of animal species. Now, the first genome of a beetle--the red flour beetle Tribolium castaneum, a pest and developmental model system alike--has been sequenced.

2012
Michael P. Moore Charles R. Burt Thomas D. Whitney Steven A. Hastings Gary C. Chang

Lady beetles typically lay eggs in clusters, and clutch-mates that emerge near to each other might benefit in multiple ways. For example, lady beetle larvae are attracted to the pheromone released by aphids under attack. Thus, one potential advantage to larvae emerging as a group is if one larva captures an aphid, others can share in consuming the same aphid. Sharing a meal likely reduces the p...

2013
Diane L. Larson James B. Grace Jennifer L. Larson

Three flea beetle species (Aphthona spp.), first introduced into North America in 1988, have come to be regarded as effective biological control organisms for leafy spurge (Euphorbia esula). The black flea beetles (Aphthona lacertosa and A. czwalinae) in particular have been shown to cause reductions in leafy spurge stem counts in the northern Great Plains, while the brown flea beetle (A. nigri...

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