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The Auchenorrhyncha (Hemiptera: Cicadomorpha and Fulgoromorpha) of Mose Farm, Shropshire: a baseline survey for the Sandscapes restoration project
Get PDFA survey of Auchenorrhyncha was undertaken as a baseline for monitoring changes arising from a long-term landscape-scale restoration project at Mose Farm in Shropshire. Surveying was completed before work began to create a mosaic of acid grass-heath, scrub and species-rich grasslands. A total of 46 taxa were recorded, including several uncommon species new to the West Midlands. Rarefaction analyses suggested other species remained undetected at low frequency. There were no clear differences in the species composition across various grassland habitats and arable field margins, although arable field margins yielded a longer species list due, in part, to higher turnover (beta diversity) between sample sites. A small number of species were numerically dominant and indicative of nutrient enrichment. However, a range of species often associated with lowland dry acid grasslands were also present in low numbers. These may be expected to increase in abundance across the site as restoration progresses. Records of the Nationally Scarce species Scottianella dalei and Ribautodelphax angulosa, and the uncommon species, R. imitans, are discussed in relation to their known distributions and host plant preferences
Can Bio-Based Stomatal Blockers Inhibit Rapeseed Growth?
Get PDFStomatal blockers are hydrophobic polymers applied to leaves to physically block stomatal pores and restrict gas exchange, and which have potential as plant growth regulators to retard growth. Three experiments in a heated glasshouse, one sown in autumn and two sown in winter, were conducted with pot-grown rapeseed plants at the four-leaf stage to evaluate retardant potential of two bio-based polymers: di-1-p-menthene (DPM) and extracted cauliflower leaf wax. Both stomatal blockers reduced stomatal conductance and plant dry weight in the autumn-sown experiment, when solar radiation was high during leaf development and stomatal conductance of water-treated plants was relatively high. Wax was more effective than DPM at reducing plant dry weight, despite no difference in stomatal conductance. In the two winter-sown experiments, when solar radiation was lower during leaf development, stomatal conductance in water-treated plants was less than in the autumn-sown experiment. Stomatal conductance was reduced by the blockers in the winter-sown experiments, but plant dry weight was unaffected. It was concluded that stomatal blockers may have potential to act as plant growth regulators to retard growth in rapeseed, but further research is necessary to define the circumstances when a response will occur
Question of compatibility: combining botanical garlic extract and entomopathogenic nematode as integrated biological control for vine weevil
No full textThis study evaluated the potential of combining the entomopathogenic nematode Steinernema kraussei, commonly used to control vine weevil, with a garlic extract-based bioinsecticide(Pitcher GR®). Steinernema kraussei survival was reduced in the presence of Pitcher GR®, decreasing from 5,280 ± 398 on Day 1–1,280 ± 196 by Day 21 in laboratory conditions. Under glasshouse conditions, the nematode alone reduced mean larval numbers to0.6 ± 0.35 compared with 10.6 ± 1.5 in the control, whereas Pitcher GR® alone was ineffective and did not enhance control. These findings highlight the importance of assessing controls compatibility for effective IPM integration
Exploring the Rural Landscape of the Marches of the Welsh Borders in Roman Times Through Intervisibility Analysis
Get PDFThe distribution of archaeological sites in the rural landscape has attracted the attention of researchers over a long period of time, leading to the several site distribution approaches that have been proposed to explain existing patterns. The main disadvantage of some of these approaches is that they assume a priori a site distribution based on some assumed behaviour such as profit maximisation, among others. The objective of this article is to propose a methodological approach, based on network theory and visibility data, that can generate models that emerge from existing data without imposing a priori assumptions on site distribution. In this approach, archaeological sites are seen as nodes, and visibility between them as links. The approach was applied to a sample of Roman Britain sites located in the Marches of the Welsh Borders. As expected, a model of site distribution emerged from the proposed approach, and the results suggest that people in the Roman period organised the landscape in subareas according to functional as well as symbolic considerations
A Theoretical Assessment of Informal Agricultural Cooperation Under Distrust: Implications from a Network Perspective
No full textA common form of cooperation in rural areas corresponds to informal alliances in which farmers save productive costs, for example, by sharing inputs, machinery, and information. By reducing costs cooperatively, these alliances contribute to agricultural land management by increasing efficiency. Despite the benefits, these alliances are typically formed by a small number of farmers. Some researchers attribute this lack of participation to distrust. To model this type of cooperation, this article extends the traditional Network of Collaboration approach which has traditionally been developed in an oligopolistic context. While oligopoly is a type of market structure that can exists in agriculture, most of the farmers who participate in informal cooperation are small enterprises suggesting that the price-taking assumption is a more realistic description for these farmers. We use this market structure extension to show that profit-maximising farmers consider the positive impact of cost reduction; the negative impact of distrust; and the expected gain in output when joining new informal alliances. As such, recommendations are provided to integrate these three factors to facilitate the formation of beneficial informal network alliances in the rural landscape and their positive externality in agricultural land management
Using radio frequency identification technology to track the movement of slugs within domestic garden habitats
Get PDFSlugs (Gastropoda: Stylommatophora) are common domestic garden inhabitants in the United Kingdom (UK) but few studies have explored the spatial behaviour of slugs within these habitats, largely due to limitations in available mark-recapture methodologies. Attempts to improve such methodologies for slugs have previously come at a high economic cost, short lifespan, and inability to detect slugs beneath the soil surface. The use of radio-frequency
identification (RFID) technology has previously shown potential in overcoming these limitations, reducing the cost
and impracticality of studying slug movement. However, this has yet to be applied to a domestic garden setting. This
study explored the potential of RFID technology to track slug movement in a UK domestic garden. Both the common
garden pests Deroceras reticulatum and Arion hortensis and the non-pestiferous Limacus maculatus were tagged with
modest to no detrimental effects on survival at 62.5%, 25%, and 0% respectively. A novel method for the containment
of D. reticulatum within a section of garden habitat was also assessed and found to be effective in containing 80% of
slugs for a period of 67 days. RFID technology was able to identify the location of D. reticulatum amongst dense garden foliage and sub-soil for 67 days, enabling slug tracking within a domestic garden habitat. No homing instinct was identified in this study when attempting to induce a home territory over a period of 67 days for the species D. reticulatum. This study demonstrates the potential of RFID technology to track the locomotion of slugs in UK domestic garden habitats and provides an opportunity to update our knowledge on this subject by overcoming the methodological limitations associated with the high cost and impracticality of studying slugs
Participación laboral por género desde una perspectiva multisectorial y regional: El caso de los Macroterritorios Norte Chico y Patagonia en Chile durante el período 2008- 2018 Labour participation by gender from a multisectoral and regional perspective: The case of the Norte Chico and Patagonia Macro-territories in Chile during the period 2008-2018
Get PDFStudies of labor participation by gender normally consider a single economic sector at the country level. Although this simplification allows obtaining appropriate results for general labor equality policies, this level of aggregation could hide more complex labor dynamics that are verified at the regional level, particularly in countries with great geographic diversity. The objective of this article is to study these dynamics in two macrozones of Chile, known for being underdeveloped areas. As expected, the results suggest that a national policy is not enough to address gender participation, since one type of economic impact has different repercussions depending on the sector and territory being analyzed. Based on this evidence, this work proposes that Local Authorities be the ones who also join National Public Policies for the leveling of labor participation
What is the evidence of human-wildlife interactions with wild mesocarnivores in Africa? A systematic map protocol
No full textMesocarnivores are small and mid-sized carnivores with a body mass of <15kg (Roemer et al., 2009). A large and taxonomically diverse group, they play an important role in the ecosystem (Curveira-Santos et al., 2021). Despite this, they are understudied (Marneweck et al., 2022) and
scientists have identified Africa, where ~30% of mesocarnivores are experiencing decreasing population trends (San et al., 2013), as an area where further research on mesocarnivores is particularly needed (San et al., 2022). Conflict with humans is one significant reason for the decline in mesocarnivore populations (Marneweck et al., 2022). They are persecuted by humans for real or perceived damage to anthropogenic resources such as livestock, crops and valuable game species (Streicher et al., 2021) and for their potential to transmit disease (Roemer et al., 2009). Although the literature has predominantly focused on human-wildlife conflict (Konig et al., 2020), human-wildlife
interactions (HWIs) may also include neutral or positive interactions (Redpath et al., 2015). Positive HWIs may result from the cultural significance attached to the species (Bhatia et al., 2020) or the ecosystem services provided by them, such as waste removal, seed dispersal and pest control (Marneweck et al., 2022). Whilst HWIs with large carnivores have been well researched, much less
scientific attention has been paid to mesocarnivores (Lozano et al., 2019). Almost one third of mesocarnivores are threatened with extinction (Marneweck et al., 2021). With the increasing frequency of HWIs due to changes in land use (Streicher et al., 2021), research is required to better understand HWIs with mesocarnivores in order to develop strategies to mitigate human-wildlife conflict and safeguard mesocarnivores. This systematic map will provide an overview of the existing research on HWIs with African mesocarnivores. The map is designed to inform future research to support landowners, conservation professionals and other decision-makers involved in mesocarnivore management
Management of stubby root nematodes (Trichodorus and Paratrichodorus spp.), associated with Docking disorder of Sugar beet (Beta vulgaris L) using brassica and non-brassica cover crops
Get PDFThis study investigated the impact of utilizing cover crops in the suppression of stubby root nematodes (Trichodorus and Paratrichodorus spp.) — SRN, and the subsequent effects on quality and quantity of sugar beet (Beta vulgaris). The active compounds associated with some of these cover crops were also evaluated for their potential nematicidal/nematostatic effects on SRN in in-vitro assays. Pure Isothiocyanates (ITCs), associated with brassicas, namely 2-phenylethyl (PEITC), allyl (AITC), and sulforaphane (SITC) were tested at different concentrations (1.625, 3.125, 6.25, 12.5, 25, and 50 μg ml−1). Effect on nematode mobility was evaluated after 24, 48, and 72 h, and mortality of SRN was assessed after 48 h of incubation in distilled water following ITC treatment.
The mortality for all ITCs at all tested concentrations was significantly higher than the controls, distilled water, and 1% DMSO. The concentration and type of ITC had a significant effect on SRN mobility and mortality, while an increase in exposure time did not significantly increase the immobility of SRN. The average 24-hour ED50 (dose resulting in 50% immobility) for SRN were 7, 5, and 44 μgml−1, and the average LD50 (dose resulting in 50% mortality) after 48 h of recovery in distilled water was 7, 11, and 24.3 μgml−1 for PEITC, AITC and SITC, respectively. The efficacy of cover crops under field conditions was tested at three locations in England: Bury St Edmunds, Suffolk (site 1) and Docking, Norfolk (site 2) and Tibberton Grange, Shropshire (site 3).
Brassica and non-brassica cover crops were tested. The cover crops included Indian mustard (Brassica juncea), oilseed radish (Raphanus sativus), daikon radish (Raphanus sativus subsp.Longipinnatus), grass with endophyte (E+), grass without endophyte (E-) (Festulolium loliaceum), Italian rye grass (Lolium multiflorum), Phacelia (Phacelia tanacefolia), and opium poppy (Papaver somniferum), stubble turnips (B. rapa), strigosa oats (Avena strigosa), clover (Trifolium alexandrinum), vetch (Vicia sativa) and vitality mix. At site 1, plots sown with brassica cover crops, specifically Indian mustard, and oilseed radish, exhibited significantly lower SRN reproduction factor (Rf) (P<0.05) compared to the fallow control and daikon radish.
In site 2, plots sown with Italian rye grass, Indian mustard, grass without endophyte (E-), or left fallow and undisturbed had a significantly higher Rf (P<0.05) compared to plots with Phacelia, opium poppy, and disturbed or sterile fallows, while in site 3, clover had significantly higher multiplication rate of SRN compared to all the other cover crops. It was four times higher than the vitality mix, three times than radish and vetch and twice higher than oats and stubble turnips. The vitality mix had the lowest SRN multiplication rate. Results from assessment of sugar beet quantity and quality parameters post cover crops indicated that sugar beet root fanging (%) and root soil tare (%) was significantly lower in cover crops and fallow plots with lower SRN Rf values, such as Phacelia, opium poppy, sterile fallow, and disturbed fallow. Environmental factors like rainfall and soil temperature also significantly impacted SRN densities at different sampling points, where SRN decreased with decreasing rain and increasing soil temperatures. The findings suggest that certain cover crops can impede SRN multiplication, despite SRN's polyphagous nature. Furthermore, factors such as weed occurrence, soil temperature, rainfall, and soil disturbance significantly affect SRN densities under field conditions.
Following the observed difference in SRN reproduction between grass with endophyte (E+) and grass without (E-) in the field trial, in-vitro experiments with shoot and root extracts were conducted to test the sensitivity of SRN to the associated compounds. Both E+ and E- extracts obtained from shoots and roots had the ability to immobilise SRN, despite the presence of the endophyte. However, a comparison of the LD50values revealed that the presence of the endophyte significantly impacted the mortality of SRN. The LD50 values of E+ extracts were lower (P<0.05) than E- extracts across all ages. Specifically, the LD50 value for shoot extracts of endophyte grass (E+) was significantly lower at 8 weeks old compared to all other ages, being twice as low as 12 weeks, 11 times lower than 16 weeks, and six times lower than 20 weeks extracts.
The LD50 for E+ root extracts at 20 weeks were half that of 12 weeks, although not significantly different from 16 weeks. In contrast, the LD50 values of root extracts from grass without endophyte followed a different pattern, increasing with the age of the grass. The LD50 value for 20-week-old plants was five times higher than that of 12- and 16-week-old plants. No mortality was recorded in the 8-week-old root extracts of both E+ and E- grass. The LD50 values also revealed that root extracts from E+ grass were more potent than those from E- grass, with the LD50 values at 12 weeks being twice as low for E+ compared to E-, and nearly 50 times lower at 20 weeks when compared to E-.
Age of the grass significantly affected loline concentration in both shoots and roots, where the concentration increased with increasing age in both shoots and roots. On the other hand, the total flavonoid content (TFC) and total phenol content (TPC) in shoot extracts decreased with age in both E+ and E- grass, with no significant differences recorded between E+ and E- grass. A negative correlation between shoot biomass and TFC (R = -0.94), and between shoot biomass and TPC (R = - 0.67) and root biomass and TPC (R = -0.79) was recorded. Upon bruising and wounding of endophyte grass (E+), the change in composition and total concentration of lolines was recorded. Specifically, NFL, NAL, and NANL were present in the 3, 7, and 11 dpb extracts but absent in the 30 days post bruising (dpb)extracts and the control. Total loline alkaloid content in the shoot extracts at 3, 7, and 11 dpb was significantly higher compared to the 30 dpb extracts and the control unbruised. This translated into lower LD50 values for shoot extracts from regrowth tissue at 3-, 7-, and 11-days post bruising (dpb) when compared to 30 dpb extracts and the control. In conclusion, this study has demonstrated potential of using brassica cover crops and non-brassica cover crops for managing SRN