Effects of spinosad on the heat tolerance and cold tolerance of Sitophilus oryzae L. (Coleoptera: Curculionidae) and Rhyzopertha dominica F. (Coleoptera: Bostrichidae)

Determinou-se a suscetibilidade de Sitophilus oryzae (L.), S. zeamais (Motsch.) e Rhyzopertha dominica (Fabr.) a dois isolados do fungo Beauveria bassiana (Bals.) Vuill. Para isso foram usados recipientes contendo arroz beneficiado, inoculado previamente com conídios dos isolados, infestados com as três espécies de insetos. Esses recipientes foram mantidos a 26 ± 0,5°C, 70 ± 10% de UR e fotofase de 12 horas. As três espécies foram suscetíveis aos dois isolados do patógeno. Os dois isolados foram eficientes para o controle de S. oryzae, na concentração de 0,5 g de conídios/100 g de grãos. Para S. zeamais, o isolado 604 foi mais eficiente na concentração de 0,1 g de conídios/100 g de grãos. Com relação a R. dominica, foram suficientes dosagens de 0,01 g (isolado 476) e 0,05 g (isolado 604)/100 g de grãos, confirmando a maior suscetibilidade desta espécie ao patógeno.

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Arboreality drives heat tolerance while elevation drives cold tolerance in tropical rainforest ants

Ecology ◽

10.1002/ecy.3549 ◽

2021 ◽

Author(s):

Lily Leahy ◽

Brett R. Scheffers ◽

Stephen E. Williams ◽

Alan N. Andersen

Keyword(s):

Cold Tolerance ◽

Heat Tolerance ◽

Tropical Rainforest

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Thermal diversity of North American ant communities: Cold tolerance but not heat tolerance tracks ecosystem temperature

Global Ecology and Biogeography ◽

10.1111/geb.13121 ◽

2020 ◽

Vol 29 (9) ◽

pp. 1486-1494 ◽

Cited By ~ 4

Author(s):

Jelena Bujan ◽

Karl A. Roeder ◽

Kirsten Beurs ◽

Michael D. Weiser ◽

Michael Kaspari

Keyword(s):

Cold Tolerance ◽

Heat Tolerance ◽

North American ◽

Ant Communities ◽

Thermal Diversity

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Mobility of Stored Product Beetles after Exposure to a Combination Insecticide Containing Deltamethrin, Methoprene, and a Piperonyl Butoxide Synergist Depends on Species, Concentration, and Exposure Time

Insects ◽

10.3390/insects11030151 ◽

2020 ◽

Vol 11 (3) ◽

pp. 151 ◽

Cited By ~ 5

Author(s):

Frank H. Arthur ◽

Christos G. Athanassiou ◽

W. Robert Morrison

Keyword(s):

Exposure Time ◽

General Pattern ◽

Sitophilus Oryzae ◽

Piperonyl Butoxide ◽

Rhyzopertha Dominica ◽

Cryptolestes Ferrugineus ◽

Curve Fit ◽

Exposure Interval ◽

Grain Protectant ◽

The Relationship

Adults of Rhyzopertha dominica (F.), the lesser grain borer, Cryptolestes ferrugineus (Stephens), the rusty grain beetle, and Sitophilus oryzae (L.), the rice weevil, were exposed for 1, 24, and 72 h on wheat treated with concentrations of 0% (untreated controls) to 100% of the proposed label rate of an experimental formulation of deltamethrin + Methoprene + piperonyl butoxide synergist. Movement and velocity of movement were assessed after each exposure time using a camera-based monitoring system (Ethovision®). Movement of R. dominica decreased with increasing concentration and exposure time, so that movement had virtually ceased at the 48 and 72 h exposures. Cryptolestes ferrugineus was less susceptible compared to R. dominica, but there was still a general pattern of decreased movement and velocity of movement with increasing concentration and exposure time. Sitophilus oryzae was the least susceptible species, with less differences at the 1 h exposure interval compared to the other two species, but after 24–72 h, the patterns of declining movement and velocity were apparent as the concentration increased. Data were analyzed using curve-fit equations to show the relationship between concentration and exposure time for each species. Results show that the Ethovison system can be used to assess the sub-lethal effects of exposure to grain protectant insecticides and elucidate behavioral variation between different stored product insects.

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Thermal tolerance patterns across latitude and elevation

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2019.0036 ◽

2019 ◽

Vol 374 (1778) ◽

pp. 20190036 ◽

Cited By ~ 34

Author(s):

Jennifer Sunday ◽

Joanne M. Bennett ◽

Piero Calosi ◽

Susana Clusella-Trullas ◽

Sarah Gravel ◽

...

Keyword(s):

Cold Tolerance ◽

Heat Tolerance ◽

Thermal Tolerance ◽

Large Scale ◽

Global Climate ◽

Climate Extremes ◽

Species Traits ◽

Acclimation Temperature ◽

Tolerance Limits ◽

Thermal Limits

Linking variation in species' traits to large-scale environmental gradients can lend insight into the evolutionary processes that have shaped functional diversity and future responses to environmental change. Here, we ask how heat and cold tolerance vary as a function of latitude, elevation and climate extremes, using an extensive global dataset of ectotherm and endotherm thermal tolerance limits, while accounting for methodological variation in acclimation temperature, ramping rate and duration of exposure among studies. We show that previously reported relationships between thermal limits and latitude in ectotherms are robust to variation in methods. Heat tolerance of terrestrial ectotherms declined marginally towards higher latitudes and did not vary with elevation, whereas heat tolerance of freshwater and marine ectotherms declined more steeply with latitude. By contrast, cold tolerance limits declined steeply with latitude in marine, intertidal, freshwater and terrestrial ectotherms, and towards higher elevations on land. In all realms, both upper and lower thermal tolerance limits increased with extreme daily temperature, suggesting that different experienced climate extremes across realms explain the patterns, as predicted under the Climate Extremes Hypothesis . Statistically accounting for methodological variation in acclimation temperature, ramping rate and exposure duration improved model fits, and increased slopes with extreme ambient temperature. Our results suggest that fundamentally different patterns of thermal limits found among the earth's realms may be largely explained by differences in episodic thermal extremes among realms, updating global macrophysiological ‘rules’. This article is part of the theme issue ‘Physiological diversity, biodiversity patterns and global climate change: testing key hypotheses involving temperature and oxygen’.

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Natural Formulation Based on Diatomaceous Earth and Botanicals against Stored Product Insects

Insects ◽

10.3390/insects11090613 ◽

2020 ◽

Vol 11 (9) ◽

pp. 613 ◽

Cited By ~ 2

Author(s):

Ivan Paponja ◽

Vlatka Rozman ◽

Anita Liška

Keyword(s):

Diatomaceous Earth ◽

Corn Oil ◽

Sitophilus Oryzae ◽

Rhyzopertha Dominica ◽

Lower Amount ◽

Favorable Effect ◽

Stored Product Insects ◽

N Form ◽

Negative Side Effects ◽

Natural Formulation

Diatomaceous earth (DE) has long been known as a potential protectant for stored cereals against various stored product insects. Despite favorable effect for the environment and human health, DE has some negative side effects on the treated commodity. In order to minimize negative response and to improve its efficacy, this paper represents a study of developed natural formulation based on DE SilicoSec® enhanced with botanicals (essential oil lavender, corn oil, and bay leaves dust) and silica gel. The activity of formulation (labeled as N Form) was tested against Sitophilus oryzae (L.), Rhyzopertha dominica (F.), and Tribolium castaneum (Herbst) in seed wheat and barley under controlled conditions. As a reference comparative value, DE SilicoSec® was used. N Form showed higher efficacy than DE, especially in barley at the lowest concentration, inducing higher mortality of all three insect species. The highest average progeny inhibition was recorded in R. dominica population both in seed wheat and barley with 94.9% and 96.3% of inhibition, respectively, followed with S. oryzae and T. castaneum inhibition of 90.6% and 86.1%, respectively, in wheat and 94.9% and 89.7%, respectively, in barley. Results indicate that the developed natural formulation N Form enhanced the activity of DE SilicoSec® using lower amount of DE dust and that it could be successfully implemented for storage of cereals as alternatives to chemical pesticides for stored product insect control.

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