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BACKGROUND

Monitoring is an integral component of integrated pest management (IPM) programmes used to inform crop management decisions. Vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae), continues to cause economically significant losses in horticultural crops due to an inability to reliably detect the presence of this species before crop damage occurs. To improve vine weevil monitoring we investigated the behavioural responses of adult vine weevils to visual (monitoring tool shade/colour, height and diameter as well as the effect of monitoring tool and plant density) and olfactory (host plant and conspecifics) cues under glasshouse conditions.

RESULTS

Monitoring tool shade, height and diameter all influenced monitoring tool efficacy, with individuals exhibiting a preference for black, tall and wide monitoring tools. The total number of individuals recorded in monitoring tools increased with monitoring tool density. By contrast, plant density did not influence the number of individuals recorded in monitoring tools. Yew-baited monitoring tools retained a larger number of individuals compared to unbaited ones. Similarly, more vine weevils were recorded in monitoring tools baited with yew and conspecifics than in unbaited monitoring tools or those baited with only yew. Baiting monitoring tools with conspecifics alone did not enhance the number of vine weevils recorded in monitoring tools.

CONCLUSIONS

Our study confirms that visual and olfactory cues influence vine weevil behaviour. This provides information on key factors that influence vine weevil monitoring tool efficacy and can be used to inform the development of a new monitoring tool for this pest. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
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Red clover (Trifolium pratense) and lucerne (Medicago sativa) are among the most common legume species used for ruminant feeding systems. Besides the greater nutritive quality and first-year ley yield compared to lucerne, red clover decreases its yield over the years. However, under unfavourable soil conditions the persistency of lucerne can be compromised, not performing as expected. This study compared yield and chemical composition of eight lucerne cultivars and one tetraploid red clover cultivar, with similar growth capacity as lucerne, replicated over two years. In the second year, four lucerne cultivars and the red clover cultivar were analysed for crude protein (CP) fractions, dry matter and neutral detergent fibre (NDF) digestibility. A randomized block design was used with three field blocks per cultivar for the multiple comparisons within each year. There were differences in DM yield, concentrations of CP and NDF and CP fractions among the lucerne cultivars, but the differences were inconsistent between years and between growth cycles within year. The red clover cultivar had lower CP and NDF concentrations than a majority of the lucerne cultivars, and greater in vitro organic matter digestibility compared to all of the lucerne cultivars. Also, the red clover cultivar had greater rumen undegradable-to-degradable CP ratio but confirmed its lower yield persistency compared to the lucerne cultivars.  相似文献   
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We investigated wheat (Triticum aestivum) grain quality under Free Air CO2 Enrichment (FACE) of 550 ± 10% CO2 μmol mol−1. In each of two full growing seasons (2008 and 2009), two times of sowing were compared, with late sowing designed to mimic high temperature during grain filling. Grain samples were subjected to a range of physical, nutritional and rheological quality assessments. Elevated CO2 increased thousand grain weight (8%) and grain diameter (5%). Flour protein concentration was reduced by 11% at e[CO2], with the highest reduction being observed at the late time of sowing in 2009, (15%). Most of the grain mineral concentrations decreased under e[CO2] - Ca (11%), Mg (7%), P (11%) and S (7%), Fe (10%), Zn (17%), Na (19%), while total uptake of these nutrients per unit ground area increased. Rheological properties of the flour were altered by e[CO2] and bread volume reduced by 7%. Phytate concentration in grains tended to decrease (17%) at e[CO2] while grain fructan concentration remained unchanged. The data suggest that rising atmospheric [CO2] will reduce the nutritional and rheological quality of wheat grain, but at high temperature, e[CO2] effects may be moderated. Reduced phytate concentrations at e[CO2] may improve bioavailability of Fe and Zn in wheat grain.  相似文献   
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Production characteristics of channel catfish (Ictalurus punctatus) reared in cages and open ponds were compared. Fish reared in open ponds had significantly better growth and food conversion ratios than fish reared in cages. Cages and open ponds stocked with fish which were closely graded in size produced fish with less size variability at harvest compared to ponds and cages stocked with nongraded and coarsely graded fish. The decrease in size variability at harvest was reflected in a greater proportion of marketable fish.  相似文献   
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