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Combined influences of transgenerational effects, temperature and insecticide on the moth Spodoptera littoralis
2021
Massot, Manuel | Bagni, Thibaut | Maria, Annick | Couzi, Philippe | Drozdz, Thomas | Malbert-Colas, Aude | Maïbèche, Martine | Siaussat, David
Climate warming is expected to impact the response of species to insecticides. Recent studies show that this interaction between insecticides and temperature can depend on other factors. Here, we tested for the influence of transgenerational effects on the Insecticide × Temperature interaction in the crop pest moth Spodoptera littoralis. Specifically, we analysed reaction norms among experimental clutches based on a split-plot design crossing the factors temperature, insecticide and clutch. The study was performed on 2280 larvae reared at four temperatures (23, 25, 27 and 29 °C), and their response to the insecticide deltamethrin (three concentrations and a control group) was tested. Temperature had a global influence with effects on larval survival, duration of development, pupal body mass, and significant reaction norms of the clutches for temperature variations of only 2 °C. In addition to the expected effect of deltamethrin on mortality, the insecticide slightly delayed the development of S. littoralis, and the effects on mortality and development differed among the clutches. Projection models integrating all the observed responses illustrated the additive effects of deltamethrin and temperature on the population multiplication rate. Variation in the response of the clutches showed that transgenerational effects influenced the impact of insecticide and temperature. Although no evidence indicated that the Insecticide × Temperature interaction depended on transgenerational effects, the studies on the dependence of the Insecticide × Temperature interaction on other factors continue to be crucial to confidently predict the combined effects of insecticides and climate warming.
Mostrar más [+] Menos [-]Pine weevil feeding on Norway spruce bark has a stronger impact on needle VOC emissions than enhanced ultraviolet-B radiation
2009
Blande, James D. | Turunen, Katariina | Holopainen, Jarmo K.
Plants can respond physiologically to damaging ultraviolet-B radiation by altering leaf chemistry, especially UV absorbing phenolic compounds. However, the effects on terpene emissions have received little attention. We conducted two field trials in plots with supplemented UV-B radiation and assessed the influence of feeding by pine weevils, Hylobius abietis L., on volatile emissions from 3-year old Norway spruce trees (Picea abies L. Karst.). We collected emissions from branch tips distal to the feeding weevils, and from whole branches including the damage sites. Weevil feeding clearly induced the emission of monoterpenes and sesquiterpenes, particularly linalool and (E)-β-farnesene, from branch tips, and the sums of monoterpenes and sesquiterpenes emitted by whole branches were substantially increased. We discovered little effect of UV-B radiation up to 30% above the ambient level on volatile emissions from branch tips distal to damage sites, but there was a possible effect on bark emissions from damage sites. Chronic exposure to enhanced UV-B radiation has little effect on volatile emissions of Norway spruce.
Mostrar más [+] Menos [-]Elevated atmospheric ozone increases concentration of insecticidal Bacillus thuringiensis (Bt) Cry1Ac protein in Bt Brassica napus and reduces feeding of a Bt target herbivore on the non-transgenic parent
2009
Himanen, Sari J. | Nerg, Anne-Marja | Nissinen, Anne | Stewart, C. Neal Jr | Poppy, Guy M. | Holopainen, Jarmo K.
Sustained cultivation of Bacillus thuringiensis (Bt) transgenic crops requires stable transgene expression under variable abiotic conditions. We studied the interactions of Bt toxin production and chronic ozone exposure in Bt cry1Ac-transgenic oilseed rape and found that the insect resistance trait is robust under ozone elevations. Bt Cry1Ac concentrations were higher in the leaves of Bt oilseed rape grown under elevated ozone compared to control treatment, measured either per leaf fresh weight or per total soluble protein of leaves. The mean relative growth rate of a Bt target herbivore, Plutella xylostella L. larvae was negative on Bt plants in all ozone treatments. On the non-transgenic plants, larval feeding damage was reduced under elevated ozone. Our results indicate the need for monitoring fluctuations in Bt toxin concentrations to reveal the potential of ozone exposure for altering dosing of Bt proteins to target and non-target herbivores in field environments experiencing increasing ozone pollution. Elevated atmospheric ozone can induce fluctuations in insecticidal protein concentrations in transgenic plants.
Mostrar más [+] Menos [-]Forest health conditions in North America
2008
Tkacz, Borys | Moody, Ben | Villa Castillo, Jamie | Fenn, Mark E.
Some of the greatest forest health impacts in North America are caused by invasive forest insects and pathogens (e.g., emerald ash borer and sudden oak death in the US), by severe outbreaks of native pests (e.g., mountain pine beetle in Canada), and fires exacerbated by changing climate. Ozone and N and S pollutants continue to impact the health of forests in several regions of North America. Long-term monitoring of forest health indicators has facilitated the assessment of forest health and sustainability in North America. By linking a nationwide network of forest health plots with the more extensive forest inventory, forest health experts in the US have evaluated current trends for major forest health indicators and developed assessments of future risks. Canada and Mexico currently lack nationwide networks of forest health plots. Development and expansion of these networks is critical to effective assessment of future forest health impacts.
Mostrar más [+] Menos [-]Short-term effects of dimethoate on metabolic responses in Chrysolina pardalina (Chrysomelidae) feeding on Berkheya coddii (Asteraceae), a hyper-accumulator of nickel
2007
Augustyniak, M. | Migula, P. | Mesjasz-Przybylowicz, J. | Tarnawska, M. | Nakonieczny, M. | Babczynska, A. | Przybylowicz, W. | Augustyniak, M.G.
Berkheya coddii Roessler (Asteraceae) is a hyper-accumulator of nickel, which can be used in phytomining and phytoremediation. Chrysolina pardalina Fabricius (Chrysomelidae) is a phytophagous leaf beetle, which may be useful in controlling population levels of B. coddii after it has been introduced into a new habitat. The aim of this study was to investigate the response of C. pardalina to topical application of dimethoate. Data recorded included the activity of acetylcholinesterase (AChE), the concentration of glutathione (GSH), and the activity of selected enzymes connected with GSH metabolism. Assays were carried out several times during the first 24 h after exposure to dimethoate. At the dosages used in this study, dimethoate was not as toxic as expected. AChE activity was significantly decreased 14 and 24 h after application. GST activity was significantly decreased 24 h after application. GSTPx activity was significantly decreased 2, 14 and 24 h after application. GR activity was significantly increased 4 h after application. GSH concentration was significantly increased 24 h after application. Long-term exposure to high levels of nickel may have caused adaptive changes in the enzymes that enable C. pardalina to deal with other stressors, including organophosphate pesticides. Long-term exposure to high levels of nickel may have caused adaptive changes in the enzymes that enable Chrysolina pardalina to deal with other stressors, including organophosphate pesticides.
Mostrar más [+] Menos [-]Conifer aphids in an air-polluted environment. II. Host plant quality
1993
Kainulainen, P. | Satka, H. | Mustaniemi, A. | Holopainen, J.K. | Oksanen, J. (Department of Environmental Sciences, University of Kuopio, PO Box 1627, SF-70211 Kuopio (Finland))
Conifer aphids in an air-polluted environment. I. Aphid density, growth and accumulation of sulphur and nitrogen by Scots pine and Norway spruce seedlings
1993
Holopainen, J.K. | Mustaniemi, A. | Kainulainen, P. | Satka, H. | Oksanen, J. (Department of Environmental Sciences, University of Kuopio, PO Box 1627, SF-70211 Kuopio (Finland))
The response of spruce shoot aphid Cinara pilicornis Hartig to ambient and filtered air at two elevations and pollution climates
1994
Holopainen, J.K. | Braun, S. | Fluckiger, W. (Ecological Laboratory, Department of Environmental Sciences, University of Kuopio, PO Box 1627, SF-70211 Kuopio (Finland))
Using golden apple snail to mitigate its invasion and improve soil quality: a biocontrol approach
2020
Wang, Jiaxin | Lu, Xuening | Zhang, Jiaen | Ouyang, Ying | Qin, Zhong | Zhao, Benliang
The invasive and widespread golden apple snail (GAS, Pomacea canaliculata) is a harmful crop pest in many parts of Asia. The heavy use of molluscicides to control GAS could result in soil and water pollution as well as in loss of biodiversity. A sustainable and pollution-free control method is urgently needed to counteract this invasion. In this study, we proposed using dried and powdered GAS residue to neutralize and fertilize soils. We compared the effects of adding GAS residue (i.e., ground GAS shell and meat residue) to the effects of adding lime upon soil properties and microbes in a greenhouse pot experiment. Each pot was incubated for 120 days, and soil pH, nutrients, microbial species, and enzyme activity were assessed. Results showed that addition of GAS residue significantly improved soil pH, contents of total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and available nitrogen but decreased soil available phosphorus (AP) content due to phosphorus sorption induced by soil organic matter (OM) and high pH. The GAS residue added to soil released nutrients and alleviated soil acidity, as well as provided more resources to soil microbes to increase their bioactivity, although lime addition was better at mitigating soil acidity. We found that with added GAS residue of 25 g kg⁻¹, the soil nitrate nitrogen (NO₃-N) content increased by 10 times; microbial biomass increased by 43%; and enzyme activity of β-1,4-glucosidase, β-1,4-N-acetylglucosaminidase, and β-D-cellobiosidase also were enhanced, compared to the control. Our findings suggest that GAS residue functions well as a fertilizer and soil amendment to aid the remediation of barren and acidic soils, making it a valuable and useful option in the control of the invasive GAS.
Mostrar más [+] Menos [-]A global perspective on the biology, impact and management of Chenopodium album and Chenopodium murale: two troublesome agricultural and environmental weeds
2019
Bajwa, Ali Ahsan | Zulfiqar, Usman | Sadia, Sehrish | Bhowmik, Prasanta | Chauhan, Bhagirath Singh
Chenopodium album and C. murale are cosmopolitan, annual weed species of notable economic importance. Their unique biological features, including high reproductive capacity, seed dormancy, high persistence in the soil seed bank, the ability to germinate and grow under a wide range of environmental conditions and abiotic stress tolerance, help these species to infest diverse cropping systems. C. album and C. murale grow tall and absorb nutrients very efficiently. Both these species are allelopathic in nature and, thus, suppress the germination and growth of native vegetation and/or crop plants. These weed species infest many agronomic and horticultural crops and may cause > 90% loss in crop yields. C. album is more problematic than C. murale as the former is more widespread and infests more number of crops, and it also acts as an alternate host of several crop pests. Different cultural and mechanical methods have been used to control these weed species with varying degrees of success depending upon the cropping systems and weed infestation levels. Similarly, allelopathy and biological control have also shown some potential, especially in controlling C. album. Several herbicides have been successfully used to control these species, but the evolution of wide-scale herbicide resistance in C. album has limited the efficacy of chemical control. However, the use of alternative herbicides in rotation and the integration of chemicals and biologically based control methods may provide a sustainable control of C. album and C. murale.
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