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221.
Dariusz Piesik Kevin J. Delaney Anna Wenda-Piesik Sebastian Sendel Piotr Tabaka Bogusław Buszewski 《Chemoecology》2013,23(4):241-250
Insect pollination and pollen feeding can reduce plant volatile emissions and future insect floral attraction, with oviposition having different effects. Meligethes aeneus F. (Coleoptera: Nitidulidae), is a pollen-feeding pest beetle of oilseed rape, Brassica napus L. (Brassicaceae). We measured plant VOC emission over 72 h from two types of 24 h M. aeneus exposure to B. napus: pollen feeding vs. flower bud injury and oviposition. The most abundant constitutive volatile organic compounds (VOCs), lilac aldehydes A (LA A) & B (LA B) and veratrole (VER), had 30–40 % reductions from M. aeneus pollen-feeding exposure at 24 h and 50–90 % reductions by 72 h, with greater reductions after bud injury and oviposition. Linalool (LIN), a common herbivore-induced plant volatile (HIPV), emission did not change at 24 h, but was induced six- to sevenfold 48 h after both exposure treatments. By 72 h, LIN had even greater (tenfold) induction after bud injury and oviposition, but no induction from pollen feeding. Three common HIPVs (β-caryophyllene, = βCAR (E)-β-farnesene = EβFAR, and (Z)-β-ocimene = ZβOCI) were progressively induced up to 2.5-fold 72 h after floral bud injury and oviposition. We assayed M. aeneus adult behavioral responses to LA A and B, and VER. Both M. aeneus sexes were attracted to higher concentrations than single plant constitutive emission for these VOCs, but avoided much higher doses. Progressive LA A and B, and VER, emission reductions might help plants (e.g., B. napus) to avoid future interactions with pollen-feeding pest herbivores (e.g., M. aeneus). After bud injury and oviposition, HIPV induction could help plants deter future oviposition and/or attract natural enemies to deposited eggs. 相似文献
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Anna Kärrman Kouji H. Harada Kayoko Inoue Takumi Takasuga Etsumasa Ohi Akio Koizumi 《Environment international》2009,35(4):712-717
Daily dietary intake of perfluorinated chemicals (PFCs) in relation to serum levels was assessed by determination of nine PFCs including perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in matched daily diet duplicates and serum samples. Diet and serum were collected in year 2004 from 20 women in Osaka and Miyagi, Japan. Only PFOS and PFOA were detected in the diet samples and no significant difference between cities was seen. After adjusted by water content, diet concentration of PFOA was significantly higher in Osaka. The median daily intake calculated using the measured diet concentrations was 1.47 ng PFOS/kg b.w. and 1.28 ng PFOA/kg b.w. for Osaka, and 1.08 ng PFOS/kg b.w. and 0.72 ng PFOA/kg b.w. for Miyagi. A significant difference between cities was seen for the serum concentrations with median of 31 ng/mL PFOS and PFOA in Osaka, compared to 14 ng/mL PFOS and 4.6 ng/mL PFOA in Miyagi. Carboxylates such as perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUnDA) were also detected in serum at median levels 6.9 ng/mL and 3.2 ng/mL (Osaka), and 2.8 ng/mL and 5.1 ng/mL (Miyagi). Based on one-compartment model under steady state, dietary intake of PFOS and PFOA accounted for only 22.4% and 23.7% of serum levels in Osaka females, and in contrast 92.5% and 110.6% in Miyagi females, respectively. 相似文献
223.
Anna Bozzano Patricia M. Pankhurst Natalie A. Moltschaniwskyj Roger Villanueva 《Marine Biology》2009,156(7):1359-1373
Eye development, optical properties and photomechanical responses were examined in embryos and hatchlings of the southern
calamary, Sepioteuthis australis. This species occurs in shallow coastal waters in Australia and New Zealand, and the egg masses were collected in October
and December 2004 from Great Oyster Bay, Tasmania. At the earliest developmental stage the eye of the squid was comprised
of a hemispherical cup of undifferentiated neural retina, while presumptive iris cell layers and lentigenic precursor cells
enclosed a posterior eye chamber. Differentiation of the proximal and distal processes was observed in correspondence with
the cornea development and lens crystallization, and occurred before differentiation of the neural retina, which was complete
prior to hatching. Longer photoreceptor distal processes were first observed just prior to hatching in the dorsal-posterior
retina. After hatching, this difference was much more evident and higher photoreceptor density was found in the central retina.
This indicates that the eye of S. australis at this age uses different retina areas for different visual tasks. Optical sensitivity and resolution suggest that juvenile
S. australis are diurnal. This study also found functional photomechanical responses of visual screening pigment migration and pupil constriction
in S. australis embryos, although complete functionality of the pupil at this stage was uncertain. However, the pupils of squid aged 2 days
closed almost completely under bright conditions, showing that photomechanical responses were highly developed in the juvenile
squid. These findings indicate that squid embryos are able to perceive visual stimulation, suggesting an early reliance on
vision for survival after hatching. 相似文献
224.
Andrei Nicoară Aurora Neagoe Paula Stancu Giovanni de Giudici Francesca Langella Anna Rosa Sprocati Virgil Iordache Erika Kothe 《Environmental science and pollution research international》2014,21(11):6905-6920
We performed an experiment at pot scale to assess the effect of plant growth-promoting bacteria (PGPB) on the development of five plant species grown on a tailing dam substrate. None of the species even germinated on inoculated unamended tailing material, prompting use of compost amendment. The effect of inoculation on the amended material was to increase soil respiration, and promote elements immobilisation at plant root surface. This was associated with a decrease in the concentrations of elements in the leaching water and an increase of plant biomass, statistically significant in the case of two species: Agrostis capillaris and Festuca rubra. The experiment was repeated at lysimeter scale with the species showing the best development at pot scale, A. capillaris, and the significant total biomass increase as a result of inoculation was confirmed. The patterns of element distribution in plants also changed (the concentrations of metals in the roots of A. capillaris and F. rubra significantly decreased in inoculated treatments, while phosphorus concentration significantly increased in roots of A. capillaris in inoculated treatment at lysimeter scale). Measured variables for plant oxidative stress did not change after inoculations. There were differences of A. capillaris plant–soil system response between experimental scales as a result of different substrate column structure and plant age at the sampling moment. Soil respiration was significantly larger at lysimeter scale than at pot scale. Leachate concentrations of As, Mn and Ni had significantly larger concentrations at lysimeter scale than at pot scale, while Zn concentrations were significantly smaller. Concentrations of several metals were significantly smaller in A. capillaris at lysimeter scale than at pot scale. From an applied perspective, a system A. capillaris—compost—PGPB selected from the rhizosphere of the tailing dam native plants can be an option for the phytostabilisation of tailing dams. Results should be confirmed by investigation at field plot scale. 相似文献
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Increasing the share of renewable energy is of principal concern for the EU energy policy. A number of policies have been adopted, and, in part, been implemented by the EU member countries. An increasing share of renewable energy implies an increasing utilisation of biofuels in general and of forest-based biomass in particular. However, in the EU, the endowment and uses of forest-base biomass are diverse suggesting that an increasing trade would become necessary in order to cost effectively increase the utilisation of forest-based biomass. The purpose of this study is to, in the presence of EU energy policy, quantify and analyse possible trade levels for forest fuels in the EU. Particularly, the consequences on trade after implementing the White Paper and the RES-E Directive are analysed. Investigating the European trade in forest fuels is important for understanding how industry sectors in the EU will be affected by the policies. The results suggest that the implementation of the White Paper and the RES-E Directive will increase the trade in forest fuels, resulting in total trade increases of up to 67 percent. Furthermore, the national net trading levels are possible to derive. Depending on policy implementation the results differ – a country that was net importing given the White Paper implementation can instead be net exporting when applying the RES-E Directive. The fact that the policy implementations will increase the trade may mitigate potential industry problems to secure the needed inputs. On the other hand, the integration of countries increases the possibility for some industries to increase their production even more, possibly strengthening any input scarcity problems. It is therefore not possible to generally conclude if a more integrated European forest fuel market, and hence an increased European forest fuel trade, will mitigate industry problems to secure their needed inputs or not. 相似文献