Occurrence of target‐site resistance to neonicotinoids in the aphid Myzus persicae in Tunisia,and its status on different host plants          下载免费PDF全文

Kamel Charaabi  Sonia Boukhris‐Bouhachem  Mohamed Makni  Ian Denholm 《Pest management science》2018,74(6):1297-1301

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Quantitative and qualitative content of alkaloids in seeds of a narrow-leafed lupin (Lupinus angustifolius L.) collection     

Katarzyna A. Kamel  Wojciech Święcicki  Zygmunt Kaczmarek  Paweł Barzyk 《Genetic Resources and Crop Evolution》2016,63(4):711-719

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Quantitative and qualitative analysis of alkaloids composition in the seeds of a white lupin (<Emphasis Type="Italic">Lupinus albus</Emphasis> L.) collection     

Magdalena Kroc  Wojciech Rybiński  Paulina Wilczura  Katarzyna Kamel  Zygmunt Kaczmarek  Paweł Barzyk  Wojciech Święcicki 《Genetic Resources and Crop Evolution》2017,64(8):1853-1860

White lupin (Lupinus albus L.) has unexploited potential as a crop plant due to its high seed yield as well as protein and oil content in seeds. Well-characterized collections of gene resources are very important for breeding as a source of genetic variation. This paper presents the results of analyses for total content and qualitative composition of alkaloids in seeds of 367 L. albus accessions from the Polish Genebank. Accessions were divided into four classes of origin: wild collected material, land races, breeding lines, and cultivars. Apart from the expected broad variation as well as strong differentiation in the alkaloid content, a clear influence of domestication was observed. This was shown as an apparent decrease in the alkaloid content in breeding lines and cultivars classes. The total alkaloid content varies from 0.02 to 12.73% of the seed dry weight. Six major alkaloids (abundance >1%) were revealed: lupanine (28.22–94.49%, mean 76.06% in total content), 13-hydroxylupanine (0.10–32.78%, mean 8.23%), multiflorine (0.00–21.67%, mean 5.52%), albine (0.00–18.55%, mean 4.48%), angustifoline (0.24–12.14%, mean 2.07%), 11,12-seco-12,13-didehydromultiflorine (0.00–12.28%, mean 1.74%). Owing to its abundance, lupanine was found to be the most closely correlated to the total alkaloid content.  相似文献   

Présence de Siphonatrophia cupressi (Hemiptera: Aphididae) en Tunisie          下载免费PDF全文

M. Ben Halima‐Kamel  L. Mdellel 《EPPO Bulletin》2017,47(3):549-550

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Effect of plant extracts and formic acid on the intestinal equilibrium of early-weaned pigs   总被引：2，自引：0，他引：2  

Manzanilla EG  Perez JF  Martin M  Kamel C  Baucells F  Gasa J 《Journal of animal science》2004,82(11):3210-3218

We evaluated the effects of a plant extracts mixture (XT) standardized in 5% (wt/wt) carvacrol, 3% cinnamaldehyde, and 2% capsicum oleoresin (oregano, cinnamon and Mexican pepper), alone or in combination with formic acid (FA), on the productive performance and the intestinal ecosystem of the early-weaned pig. Pigs weaned at 20 +/- 1 d of age (n = 216) were allocated in 24 pens and fed a standard medicated prestarter diet for 12 d. Twelve days after weaning, a stress management system based on social and dietary stress factors was applied to the animals, after which, each group was allocated to one of six dietary treatments, which followed a factorial arrangement, with three levels (as-fed basis) of the XT (0, 150, and 300 mg/kg) and two levels of FA (0 and 0.5%). On d 24 and 25 after the stress episode, eight pigs per treatment were killed to examine variables describing some aspects of the gastrointestinal ecology. Two days after the stress episode, an Escherichia coli K88 diarrhea episode occurred, and five casualties were registered. Four of the five deaths occurred in pens of pigs not fed the XT. The FA resulted in better G:F (P = 0.040) in coincidence with shorter villous height (P = 0.073) and lower rectal total microbial mass (P = 0.078). Both XT and FA addition increased stomach content (P = 0.006 and 0.003, respectively) and percentage of DM (P = 0.089 and 0.010, respectively), suggesting an increased gastric retention time; consequently, pH was also increased (P = 0.005 and 0.060, respectively). The XT decreased ileum total microbial mass (P = 0.025) and increased the lactobacilli:enterobacteria ratio (P = 0.002). The VFA profile in the cecum and colon was modified by XT inclusion, increasing the proportion of acetate (P = 0.018 and 0.025, respectively) and diminishing the proportion of butyrate (P = 0.096 and 0.040, respectively) and valerate (P = 0.001 and 0.039, respectively). Both XT and FA were shown to be effective in modifying the gastrointestinal ecosystem, stomach contents, and stomach emptying rate, which are proposed as important aspects in the mechanisms of action for these additives.  相似文献   

Carbon isotopic signature of CO2 emitted by plant compartments and soil in two temperate deciduous forests     

Florence Maunoury-Danger  Nicolas Chemidlin Prevost Boure  Jérôme Ngao  Daniel Berveiller  Claude Brechet  Eric Dufrene  Daniel Epron  Jean-Christophe Lata  Bernard Longdoz  Caroline Lelarge-Trouverie  Jean-Yves Pontailler  Kamel Soudani  Claire Damesin 《Annals of Forest Science》2013,70(2):173-183

? Context

The carbon isotope composition of the CO₂ efflux (δ¹³C_E) from ecosystem components is widely used to investigate carbon cycles and budgets at different ecosystem scales. δ¹³C_E, was considered constant but is now known to vary along seasons. The seasonal variations have rarely been compared among different ecosystem components.

? Aims

We aimed to characterise simultaneously the seasonal dynamics of δ¹³C_E in different compartments of two temperate broadleaved forest ecosystems.

? Methods

Using manual chambers and isotope ratio mass spectrometry, we recorded simultaneously δ¹³C_E and δ¹³C of organic matter in sun leaves, current-year twigs, trunk bases and soil in an oak and a beech forest during 1 year.

? Results

In the two forests, δ¹³C_E displayed a larger variability in the tree components than in the soil. During the leafy period, a pronounced vertical zonation of δ¹³C_E was observed between the top (sun leaves and twigs with higher values) and bottom (trunk and soil with lower values) of the ecosystem. No correlation was found between δ¹³C_E and δ¹³C of organic matter. Causes for these seasonal variations and the vertical zonation in isotope signature are discussed.

? Conclusion

Our study shows clear differences in values as well as seasonal dynamics of δ¹³C_E among different components in the two ecosystems. The temporal and local variation of δ¹³C_E cannot be inferred from organic matter signature or CO₂ emission rates.  相似文献   

Insecticide residues in pollen and nectar of a cucurbit crop and their potential exposure to pollinators     

Dively GP  Kamel A 《Journal of agricultural and food chemistry》2012,60(18):4449-4456

Neonicotinoids are systemic insecticides widely used on many pollinated agricultural crops, and increasing evidence indicates that they move to some extent into pollen and nectar. This study measured levels of neonicotinoid residues in pollen and nectar from a pumpkin crop treated with formulated products containing imidacloprid, dinotefuran, and thiamethoxam using different timings and application methods. Environmental conditions have a significant effect on overall residue levels; nectar residues were 73.5-88.8% less than pollen residues, and metabolites accounted for 15.5-27.2% of the total residue amounts. Foliar-applied treatments and chemigated insecticides applied through drip irrigation during flowering resulted in the highest residues of parent insecticide and metabolites, which may reach average levels up to 122 ng/g in pollen and 17.6 ng/g in nectar. The lowest levels of residues were detected in treatment regimens involving applications of insecticides at planting, as either seed dressing, bedding tray drench, or transplant water treatment.  相似文献   

Tracheal respiration in insects visualized with synchrotron x-ray imaging     

Westneat MW  Betz O  Blob RW  Fezzaa K  Cooper WJ  Lee WK 《Science (New York, N.Y.)》2003,299(5606):558-560

Insects are known to exchange respiratory gases in their system of tracheal tubes by using either diffusion or changes in internal pressure that are produced through body motion or hemolymph circulation. However, the inability to see inside living insects has limited our understanding of their respiration mechanisms. We used a synchrotron beam to obtain x-ray videos of living, breathing insects. Beetles, crickets, and ants exhibited rapid cycles of tracheal compression and expansion in the head and thorax. Body movements and hemolymph circulation cannot account for these cycles; therefore, our observations demonstrate a previously unknown mechanism of respiration in insects analogous to the inflation and deflation of vertebrate lungs.  相似文献