02611nas a2200169   4500008004100000020001400041245008100055210006900136260001200205300001200217490000800229520203500237653001902272100002302291700002302314856010402337       2010                        eng d  a0029-854900aElevated CO2 and aboveground-belowground herbivory by the clover root weevil0 aElevated CO2 and abovegroundbelowground herbivory by the clover   cJanuary  a209-2160 v1623 aPredicted increases in atmospheric carbon dioxide (CO2) concentrations are expected to increase primary productivity in many terrestrial ecosystems, which could lead to plants becoming N limited. Studies suggest that legumes may partially overcome this by increasing biological nitrogen fixation. However, these studies have not yet considered how these changes may be affected by the altered dynamics of insect herbivores feeding on the plant. This study investigated how elevated CO2 (700 [mu]l l-1) affected the clover root weevil (Sitona lepidus), a significant pest of white clover (Trifolium repens). Adults feed on leaves aboveground where they lay eggs; soil-dwelling larvae initially feed on root nodules that house N2-fixing bacteria. Foliar C:N ratios rose by 9% at elevated CO2, but the biggest responses were observed belowground, with increases in root mass (85% greater) and nodule abundance (220% more abundant). Root C:N ratios increased significantly from 10.95 to 11.60 under elevated CO2, which increased even further to 13.13 when nodules were attacked by larval S. lepidus. Adult S. lepidus consumed significantly more leaf tissue at elevated CO2 (0.47 cm2 day-1) compared with ambient CO2 (0.35 cm2 day-1), suggesting compensatory feeding, but laid 23% fewer eggs at elevated CO2. Even though fewer eggs were laid at elevated CO2, 38% more larvae were recovered suggesting that larval survival was much better under elevated CO2. Increased larval abundance and performance at elevated CO2 were positively correlated with the number of nodules available. In conclusion, reduced foliar quality at elevated CO2 was generally disadvantageous for adult S. lepidus living aboveground, but extremely beneficial for S. lepidus larvae living belowground, due to the enhanced nodulation. Climate change may, therefore, enhance biological nitrogen fixation by T. repens, but potential benefits (e.g. provision of N without chemical fertilizers) may be undermined by larger populations of S. lepidus larvae belowground.10aSitona lepidus1 aJohnson, Scott, N.1 aMcNicol, James, W.  uhttps://weevil.myspecies.info/elevated-co2-and-aboveground-belowground-herbivory-clover-root-weevil02355nas a2200193   4500008004100000020001400041245010800055210006900163260000800232300001200240490000700252520165100259653002601910100002301936700002501959700002501984700002202009856013002031       2010                        eng d  a1461-955500aProtected raspberry production accelerates onset of oviposition by vine weevils (Otiorhynchus sulcatus)0 aProtected raspberry production accelerates onset of oviposition   cAug  a277-2830 v123 aSoft fruit production is increasingly reliant on crops that are grown under the protection of plastic tunnels, which may also affect insect communities as a result of localized climate change and changes to host plant physiology and chemistry. In particular, insect development rates may differ from field populations, making it more difficult to target control measures. The present study investigated how protected environments affected adult vine weevil (Otiorhynchus sulcatus) feeding and reproduction on red raspberry (Rubus idaeus). We focused on the period between adult emergence and the onset of oviposition (i.e. the pre-reproductive period), which represents the optimal period for control. Tunnels were up to 4 [degree]C warmer than field plantations in 2008, with plants growing significantly faster (50% increase in height and 16% increase in leaf area) than field grown plants. The carbon/nitrogen ratio in leaves was higher in tunnels (12.07) than the field (10.89) as a result of a significant decrease in nitrogen concentrations (3.40 and 3.90 mg g-1, respectively). Over 4 weeks, weevils consumed significantly more foliage in tunnels (370.89 mg) than weevils in the field (166.68 mg), suggesting compensatory feeding to counteract lower leaf nitrogen concentrations. Weevils in tunnels achieved sexual maturity 8 days earlier than those in the field and produced 20-fold more eggs by the time they were 5 weeks old. Applying a degree-day model showed good agreement between predicted and observed pre-reproductive periods for weevils in tunnels (36 and 30 days, respectively) and in field plots (41 and 38 days, respectively).10aOtiorhynchus sulcatus1 aJohnson, Scott, N.1 aPetitjean, Sebastien1 aClark, Katherine, E.1 aMitchell, Carolyn  uhttps://weevil.myspecies.info/protected-raspberry-production-accelerates-onset-oviposition-vine-weevils-otiorhynchus-sulcatus02792nas a2200217   4500008004100000020001400041245014400055210006900199260001300268300001200281490000700293520197100300653002602271100002302297700002102320700002502341700002302366700002602389700002402415856013502439       2011                        eng d  a1354-101300aElevated atmospheric carbon dioxide impairs the performance of root-feeding vine weevils by modifying root growth and secondary metabolites0 aElevated atmospheric carbon dioxide impairs the performance of r  cFebruary  a688-6950 v173 aPredicting how insect crop pests will respond to global climate change is an important part of increasing crop production for future food security, and will increasingly rely on empirically based evidence. The effects of atmospheric composition, especially elevated carbon dioxide (eCO2), on insect herbivores have been well studied, but this research has focussed almost exclusively on aboveground insects. However, responses of root-feeding insects to eCO2 are unlikely to mirror these trends because of fundamental differences between aboveground and belowground habitats. Moreover, changes in secondary metabolites and defensive responses to insect attack under eCO2 conditions are largely unexplored for root herbivore interactions. This study investigated how eCO2 (700 [mu]mol mol-1) affected a root-feeding herbivore via changes to plant growth and concentrations of carbon (C), nitrogen (N) and phenolics. This study used the root-feeding vine weevil, Otiorhynchus sulcatus and the perennial crop, Ribes nigrum. Weevil populations decreased by 33% and body mass decreased by 23% (from 7.2 to 5.4 mg) in eCO2. Root biomass decreased by 16% in eCO2, which was strongly correlated with weevil performance. While root N concentrations fell by 8%, there were no significant effects of eCO2 on root C and N concentrations. Weevils caused a sink in plants, resulting in 8-12% decreases in leaf C concentration following herbivory. There was an interactive effect of CO2 and root herbivory on root phenolic concentrations, whereby weevils induced an increase at ambient CO2, suggestive of defensive response, but caused a decrease under eCO2. Contrary to predictions, there was a positive relationship between root phenolics and weevil performance. We conclude that impaired root-growth underpinned the negative effects of eCO2 on vine weevils and speculate that the plant's failure to mount a defensive response at eCO2 may have intensified these negative effects.10aOtiorhynchus sulcatus1 aJohnson, Scott, N.1 aBarton, Adam, T.1 aClark, Katherine, E.1 aGregory, Peter, J.1 aMcMenemy, Lindsay, S.1 aHancock, Robert, D.  uhttps://weevil.myspecies.info/elevated-atmospheric-carbon-dioxide-impairs-performance-root-feeding-vine-weevils-modifying-root-gro02878nas a2200217   4500008004100000020001400041245012200055210006900177260001200246300001000258490000700268520209800275653001902373100002302392700002302415700002302438700002102461700002002482700002302502856013502525       2010                        eng d  a0929-139300aEffects of soil conditions and drought on egg hatching and larval survival of the clover root weevil (Sitona lepidus)0 aEffects of soil conditions and drought on egg hatching and larva  cJanuary  a75-790 v443 aSoil-dwelling insect herbivores are significant pests in many managed ecosystems. Because eggs and larvae are difficult to observe, mathematical models have been developed to predict life-cycle events occurring in the soil. To date, these models have incorporated very little empirical information about how soil and drought conditions interact to shape these processes. This study investigated how soil temperature (10, 15, 20 and 25 [degree]C), water content (0.02 (air dried), 0.10 and 0.25 g g-1) and pH (5, 7 and 9) interactively affected egg hatching and early larval lifespan of the clover root weevil (Sitona lepidus Gyllenhal, Coleoptera: Curculionidae). Eggs developed over 3.5 times faster at 25 [degree]C compared with 10 [degree]C (hatching after 40.1 and 11.5 days, respectively). The effect of drought on S. lepidus eggs was investigated by exposing eggs to drought conditions before wetting the soil (2-12 days later) at four temperatures. No eggs hatched in dry soil, suggesting that S. lepidus eggs require water to remain viable. Eggs hatched significantly sooner in slightly acidic soil (pH 5) compared with soils with higher pH values. There was also a significant interaction between soil temperature, pH and soil water content. Egg viability was significantly reduced by exposure to drought. When exposed to 2-6 days of drought, egg viability was 80-100% at all temperatures but fell to 50% after 12 days exposure at 10 [degree]C and did not hatch at all at 20 [degree]C and above. Drought exposure also increased hatching time of viable eggs. The effects of soil conditions on unfed larvae were less influential, except for soil temperature which significantly reduced larval longevity by 57% when reared at 25 [degree]C compared with 10 [degree]C (4.1 and 9.7 days, respectively). The effects of soil conditions on S. lepidus eggs and larvae are discussed in the context of global climate change and how such empirically based information could be useful for refining existing mathematical models of these processes. [copyright] 2009 Elsevier B.V. All rights reserved.10aSitona lepidus1 aJohnson, Scott, N.1 aGregory, Peter, J.1 aMcNicol, James, W.1 aOodally, Yasmina1 aZhang, Xiaoxian1 aMurray, Philip, J.  uhttps://weevil.myspecies.info/effects-soil-conditions-and-drought-egg-hatching-and-larval-survival-clover-root-weevil-sitona-lepid02603nas a2200193   4500008004100000020001400041245012000055210006900175260000800244300001200252490000800264520188400272653002602156100002102182700002502203700002302228700002302251856013502274       2011                        eng d  a0013-870300aPrior host feeding experience influences ovipositional but not feeding preference in a polyphagous insect herbivore0 aPrior host feeding experience influences ovipositional but not f  cFeb  a137-1450 v1383 aBlack vine weevils, Otiorhynchus sulcatus (Fabricius) (Coleoptera: Curculionidae), are globally-distributed polyphagous pests of many horticultural crops. We investigated how adult weevils were affected by host switching and, in particular, how host plant species nutritional and defensive chemistry affected subsequent host plant species selection and oviposition. Adults were fed one of three host plant species, blackcurrant (Ribes nigrum L. (Grossulariaceae)), raspberry (Rubus idaeus L. (Rosaceae)), or strawberry (Fragaria x ananassa Duchesne (Rosaceae)), throughout their pre-reproductive periods and then subjected to behavioral choice assays with these plants. Foliar chemistry differed significantly among the three host plant species. Compared to raspberry and strawberry foliage, blackcurrant foliage was 13% lower in nitrogen, 3% higher in carbon, and 28% higher in phenolic compounds. Initial host plant species had a significant effect on weevil mortality, with more weevils dying when previously fed blackcurrant (12%) than strawberry (3%) or raspberry (0%) regardless of subsequent host. Initial host plant species also affected oviposition, with weevils laying only ca. two eggs per week when previously fed blackcurrant, compared to those on raspberry or strawberry (ca. 11 and 15 eggs per week, respectively). When given a choice, weevils discriminated among host plant species and tended to oviposit on plants on which they had previously fed, even when the plant was nutritionally inferior for egg production and adult survival. In contrast, feeding behavior was only affected by the current host plant species. Feeding and oviposition were related to leaf chemistry only in blackcurrant, as leaf consumption was negatively correlated with foliar carbon and zinc concentrations, and positively correlated with foliar phosphorus and potassium concentrations.10aOtiorhynchus sulcatus1 aCoyle, David, R.1 aClark, Katherine, E.1 aRaffa, Kenneth, F.1 aJohnson, Scott, N.  uhttps://weevil.myspecies.info/prior-host-feeding-experience-influences-ovipositional-not-feeding-preference-polyphagous-insect-her02661nas a2200229   4500008004100000020001400041245015300055210006900208260000800277300001000285490000700295520181100302100002502113700002302138700002102161700002002182700002602202700002302228700002202251700002302273856013502296       2012                        eng d  a0261-219400aEffects of cultivar and egg density on a colonizing vine weevil (Otiorhynchus sulcatus) population and its impacts on red raspberry growth and yield0 aEffects of cultivar and egg density on a colonizing vine weevil   cFeb  a76-820 v323 aBlack vine weevil (Otiorhynchus sulcatus) is regarded as a damaging pest of horticultural crops, yet empirical data about its population dynamics and effects on crop yield are largely lacking. This paper reports a four year (2007-2010) field study that simulated colonisation by O. sulcatus in a red raspberry (Rubus idaeus) plantation comprising two cultivars (Glen Ample and Glen Rosa). The study tested whether adult O. sulcatus abundance was affected by cultivar or original egg distribution. Total population estimates were also made using mark and recapture methods. Finally, the effects of O. sulcatus on plant growth and berry yield were quantified. O. sulcatus abundance was significantly higher on Glen Ample than Glen Rosa, with the difference becoming even greater in 2009 compared to 2008. The abundance of O. sulcatus adults on particular plants was not related to original egg density. Mark and recapture based estimates suggested that the overall O. sulcatus population reached 3500 in 2008 and 44,100 in 2009. O. sulcatus abundance on plants was negatively related to plant height. Comparing plants with greatest and lowest O. sulcatus burdens showed that the heavily infested plants had lower shoot and root biomass in both Glen Ample (62% and 60%, respectively) and Glen Rosa (50% and 12%, respectively), significantly smaller berries (5.1 g and 2.8 g, respectively, in Glen Ample and 3.3 g and 2.7 g, respectively, in Glen Rosa) and smaller yields (2.93 kg and 0.99 kg in Glen Ample and 2.80 kg-1.71 kg in Glen Rosa, respectively). While cane fruits like raspberry were thought to tolerate O. sulcatus attack due to extensive root systems, this study suggests that damage can be extensive, particularly on cultivars such as Glen Ample. [copyright]2011 Elsevier Ltd. All rights reserved.1 aClark, Katherine, E.1 aHartley, Susan, E.1 aBrennan, Rex, M.1 aJennings, Nikki1 aMcMenemy, Lindsay, S.1 aMcNicol, James, W.1 aMitchell, Carolyn1 aJohnson, Scott, N.  uhttps://weevil.myspecies.info/effects-cultivar-and-egg-density-colonizing-vine-weevil-otiorhynchus-sulcatus-population-and-its-imp02437nas a2200193   4500008004100000020001400041245014700055210006900202260000800271300002200279490000700301520168700308100002501995700002302020700002102043700002202064700002302086856013402109       2012                        eng d  a1461-955500aOviposition and feeding behaviour by the vine weevil Otiorhynchus sulcatus on red raspberry: effects of cultivars and plant nutritional status0 aOviposition and feeding behaviour by the vine weevil Otiorhynchu  cMay  aNIL_0044-NIL_00510 v143 a1 The vine weevil Otiorhynchus sulcatus is a major pest of horticultural crops worldwide, with root-feeding larvae causing most damage. Adult oviposition aboveground may therefore influence levels of damage as the larvae are relatively immobile after oviposition. 2 The present study investigated feeding and oviposition behaviour on red raspberry Rubus idaeus using intact plants, ensuring that choices reflected the realistic differences in cultivar appearance and chemical composition. Previous studies investigating vine weevil feeding and oviposition on other crops have used excised plant material, which may inadvertently influence behaviour. 3 Adult weevils significantly preferred to feed on particular cultivars in the choice experiment (e.g. Tulameen), although they consumed significantly more foliage (0.221.03 cm2/day) on different raspberry cultivars (e.g. Glen Moy, Glen Rosa and a wild accession) in no-choice situations. 4 In choice experiments, weevils tended to avoid laying eggs on some cultivars (e.g. Glen Moy and the wild accession). The number of eggs laid (1.914.32 eggs per day) did not, however, differ significantly between the cultivars in a no-choice situation. Foliar nitrogen and magnesium concentrations were positively, although weakly, correlated with the total number of eggs laid. 5 The present study highlights the importance of considering both choice and no-choice tests when assessing crop susceptibility to attack because weevils may avoid feeding on certain cultivars (e.g. Glen Moy) when given a choice, although this would cause significant damage to such cultivars if they were grown in monoculture (i.e. when there is no alternative).1 aClark, Katherine, E.1 aHartley, Susan, E.1 aBrennan, Rex, M.1 aMacKenzie, Katrin1 aJohnson, Scott, N.  uhttps://weevil.myspecies.info/oviposition-and-feeding-behaviour-vine-weevil-otiorhynchus-sulcatus-red-raspberry-effects-cultivars02426nas a2200169   4500008004100000020001400041245014400055210006900199260000800268300001200276490000700288520175500295100002502050700002302075700002302098856013502121       2011                        eng d  a0307-694600aDoes mother know best? The preference-performance hypothesis and parent-offspring conflict in aboveground-belowground herbivore life cycles0 aDoes mother know best The preferenceperformance hypothesis and p  cApr  a117-1240 v363 a1. A substantial amount of research on host- plant selection by insect herbivores is focused around the preference- performance hypothesis (PPH). To date, the majority of studies have primarily considered insects with aboveground life cycles, overlooking insect herbivores that have both aboveground and belowground life stages, for which the PPH could be equally applicable. 2. This study investigated the factors influencing the performance of the root-feeding vine weevil (Otiorhynchus sulcatus) larvae and whether this was linked to the oviposition behaviour of the maternal adult living aboveground. 3. Maternal insects feeding aboveground reduced root biomass by 34% and increased root carbon by 4%. Larvae feeding on plants subjected to aboveground herbivory had reduced mass. Irrespective of the presence of maternal herbivory, larval mass was positively correlated with root biomass. 4. Larval mass was also reduced by conspecific larvae, previously feeding on roots (19% reduction). However, the mechanism underpinning this effect remains unclear, as in contrast to maternal herbivory aboveground, prior larval feeding did not significantly affect root biomass or root carbon concentrations. 5. Maternal insects did not distinguish between plants infested with larvae and those that were free of larvae, in terms of their egg-laying behaviour. Conversely, maternal insects tended to lay eggs on plants with smaller root systems, a behaviour that is likely to negatively affect offspring performance. 6. The PPH is not supported by our findings for the polyphagous vine weevil feeding on the host plant raspberry (Rubus idaeus), and in fact our results suggest that there is the potential for strong parent-offspring conflict in this system.1 aClark, Katherine, E.1 aHartley, Susan, E.1 aJohnson, Scott, N.  uhttps://weevil.myspecies.info/does-mother-know-best-preference-performance-hypothesis-and-parent-offspring-conflict-aboveground-be