Evaluation of the Francome MkII exhaust nozzle sprayer to apply oil-based formulations of Metarhizium flavoviride for locust control

Conidia of the fungus Metarhizium flavoviride were formulated in a paraffinic oil, ‘Shellsol’ T, and sprayed using the Francome MkII exhaust nozzle sprayer. Germination of the conidia collected from the spray was reduced by 30% as compared to unsprayed conidia. However, in bioassays, there was no detectable difference in virulence with conidia collected from the spray samples and unsprayed formulation. This indicated that, despite the recorded reduction in the concentration of active conidia, the efficacy of the formulation remained unchanged after passing through the exhaust nozzle sprayer. The droplet size spectra produced by the sprayer were investigated using the Malvern series 2600cc particle size analyser. The optimum droplets for locust control produced by this sprayer were generated by the number 1 nozzle (internal diameter 2·5 mm) with the number 1 restrictor ring (internal diameter 12.5 mm) sprayed at a pressure of 0·2 bar. The droplets thus produced had a volume median diameter of 58 μm when the nozzle protruded between 1 and 2 mm above the level of the restrictor ring. Of the droplets in the spray plume created by these conditions, 33% were between 50 and 100 μm, a range recommended as an achievable optimum for the ultra-low-volume application of Metarhizium flavoviride. The role of the exhaust nozzle sprayer as a tool for the application of M. flavoviride for locust control is discussed with reference to other vehicle-mounted ultra-low-volume sprayers. © 1997 SCI     

Validation of the TonoVet® rebound tonometer in normal and glaucomatous cats

Objective  To validate intraocular pressure (IOP) readings obtained in cats with the TonoVet^® tonometer. Animals studied  IOP readings obtained with the TonoVet^® were compared to IOP readings determined by manometry and by the Tono‐Pen XL^? in 1 normal cat and two glaucomatous cats. TonoVet^® and Tono‐Pen XL^? readings were also compared in a further six normal and nine glaucomatous cats. Procedures  The anterior chambers of both eyes of three anesthetized cats were cannulated and IOP was varied manometrically, first increasing from 5 to 70 mmHg in 5 mmHg increments, then decreasing from 70 to 10 mmHg in 10 mmHg decrements. At each point, two observers obtained three readings each from both eyes, with both the TonoVet^® and Tono‐Pen XL^?. IOP was measured weekly for 8 weeks with both tonometers in six normal and nine glaucomatous unsedated cats. Data were analyzed by linear regression. Comparisons between tonometers and observers were made by paired student t‐test. Results  The TonoVet^® was significantly more accurate than the Tono‐Pen XL^? (P = 0.001), correlating much more strongly with manometric IOP. In the clinical setting, the Tono‐Pen XL^? underestimated IOP when compared with the TonoVet^®. Conclusions  Both the TonoVet^® and Tono‐Pen XL^? provide reproducible IOP measurements in cats; however, the TonoVet^® provides readings much closer to the true IOP than the Tono‐Pen XL^?. The TonoVet^® is superior in accuracy to the Tono‐Pen XL^? for the detection of ocular hypertension and/or glaucoma in cats in a clinical setting.     

Scale-specific land cover thresholds for conservation of stream invertebrate communities in agricultural landscapes

Context

In agricultural landscapes, riparian forests are used as a management tool to protect stream ecosystems from agricultural activities. However, the ability of managers to target stream protection actions is limited by incomplete knowledge of scale-specific effects of agriculture in riparian corridor and catchment areas.

Objectives

We evaluated scale-specific effects of agricultural cover in riparian corridor and catchment areas on stream benthic macroinvertebrate (BMI) communities to develop cover targets for agricultural landscapes.

Methods

Sixty-eight streams assigned to three experimental treatments (Forested Riparian, Agricultural Riparian, Agricultural Catchment) were sampled for BMIs. Ordination and segmented regression were used to assess impacts of agriculture on BMI communities and detect thresholds for BMI community metrics.

Results

BMI communities were not associated with catchment agricultural cover where the riparian corridor was forested, but were associated with variation in catchment agriculture where riparian forests had been converted to agriculture. Trait-based metrics showed threshold responses at greater than 70% agricultural cover in the catchment. Increasing agriculture in the riparian corridor was associated with less diverse and more tolerant BMI communities. Eight metrics exhibited threshold responses ranging from 45 to 75% agriculture in the riparian corridor.

Conclusions

Riparian forest effectively buffered streams from agricultural activity even where catchment agriculture exceeds 80%. We recommend managers prioritize protection of forested riparian corridors and that restore riparian corridors where agricultural cover is near identified thresholds be a secondary priority. Adoption of catchment management actions should be effective where the riparian corridor has been converted to agriculture.

     

Development and evaluation of a high-throughput,low-cost genotyping platform based on oligonucleotide microarrays in rice

Background  

We report the development of a microarray platform for rapid and cost-effective genetic mapping, and its evaluation using rice as a model. In contrast to methods employing whole-genome tiling microarrays for genotyping, our method is based on low-cost spotted microarray production, focusing only on known polymorphic features.     

A new framework of spatial targeting for single-species conservation planning

Context

Organisations acting to conserve and protect species across large spatial scales prioritise to optimise use of resources. Spatial conservation prioritization tools typically focus on identifying areas containing species groups of interest, with few tools used to identify the best areas for single-species conservation, in particular, to conserve currently widespread but declining species.

Objective

A single-species prioritization framework, based on temporal and spatial patterns of occupancy and abundance, was developed to spatially prioritize conservation action for widespread species by identifying smaller areas to work within to achieve predefined conservation objectives.

Methods

We demonstrate our approach for 29 widespread bird species in the UK, using breeding bird atlas data from two periods to define distribution, relative abundance and change in relative abundance. We selected occupied 10-km squares with abundance trends that matched species conservation objectives relating to maintaining or increasing population size or range, and then identified spatial clusters of squares for each objective using a Getis-Ord-Gi* or near neighbour analysis.

Results

For each species, the framework identified clusters of 20-km squares that enabled us to identify small areas in which species recovery action could be prioritized.

Conclusions

Our approach identified a proportion of species’ ranges to prioritize for species recovery. This approach is a relatively quick process that can be used to inform single-species conservation for any taxa if sufficiently fine-scale occupancy and abundance information is available for two or more time periods. This is a relatively simple first step for planning single-species focussed conservation to help optimise resource use.

     

Green roof vegetation type affects germination and initial survival of colonizing woody species

Green roofs provide a number of valuable ecosystem services compared to conventional roofs, but may require yearly maintenance. Trees and other woody plants that persist on the roof may damage or overload shallow-substrate green roofs and their removal is a standard maintenance procedure. The germination potential of colonizing species may differ depending on the vegetation surrounding them. The aim of this study was to determine whether the germination of colonizing tree species (Picea glauca and Ulmus glabra) will vary depending on which plant species form the established vegetation seeds land in. To determine germination success, survival, and seed capture ability of the plant canopy, tree seeds were added either directly to the growing medium or atop the plant canopy, in replicated monocultures of 14 species native to Nova Scotia. When seeds were added directly to the soil, no significant difference was detected between the monocultures for germination success or survival for U. glabra or P. glauca. However, when the seeds were added atop the plant canopy, percent germination of U. glabra was significantly higher in Carex argyrantha green roof modules. Overall, sod forming graminoids showed higher germination of U. glabra. The number of seeds reaching the soil was typically lower in vegetation with a denser canopy. This study demonstrates that some vegetation repels colonizing tree species by reducing ground contact. Although these effects differed according to tree species, non-vegetated substrates enhanced seedling persistence. Additionally, the majority of tree seeds that germinated failed to survive a single growing-season on shallow-substrate green roofs.     

The EPPO prioritization process for invasive alien plants

Although invasive alien plants are gaining increased attention within EPPO countries, there is no existing widely agreed method to identify those alien plants that are considered invasive and represent the highest priority for pest risk analysis. In the framework of the ad hoc Panel on Invasive Alien Species, EPPO proposes a prioritization process for invasive alien plants designed (i) to produce a list of invasive alien plants that are established or could potentially establish in the EPPO region and (ii) to determine which of these have the highest priority for an EPPO pest risk analysis. The process consists of compiling available information on alien plants according to pre‐determined criteria, and can be run at the EPPO region level, or at a country or local area level. These criteria examine whether the species is alien in the area under study, and whether it is established or not. The criteria used primarily rely on observations in the EPPO region but, if the species is not established, the invasive behaviour of the species in other countries should be investigated, as well as the suitability of the ecoclimatic conditions in the area under consideration. The spread potential, the potential negative impacts on native species, habitats and ecosystems, as well as on agriculture, horticulture or forestry are considered. If the species qualifies as an invasive alien plant of major concern through this first set of questions, the process then investigates the efficiency of international measures (to be justified through a pest risk analysis) to prevent the entry and spread of the species. The second set of questions are designed to determine whether the species is internationally traded or enters new countries through international pathways for which the risk of introduction is superior to natural spread, and whether the species still has a significant suitable area for further spread. If used by several EPPO countries, this prioritization process represents an opportunity to provide consistent country lists of invasive alien plant species, as well as a tool for dialogue and exchange of information.     

Effect of adjuvants on the performance of the new cereal fungicide,metconazole. I glasshouse trials

Metconazole, (1RS, 5RS; 1RS, 5SR)-5-(4-chlorobenzyl)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol, is a highly active fungicide, in particular controlling seed-borne and foliar diseases of cereals, such as wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). In order to maximize its foliar activity, an experimental survey of some types of surfactants and an emulsifiable oil was undertaken. Two types of metconazole formulation were investigated using a biological assay involving the therapeutic control of two diseases (Erysiphe graminis DC f. sp. tritici Marchal and Leptosphaeria nodorum Muell.) of wheat. Enhancements of activity by ?Genapol’? C12/C14 alcohol ethoxylates of an emulsifiable concentrate (ECM) formulation of metconazole were approximately three- to four-fold. For its, initially, less active suspension concentrate (SCM) formulation, enhancements were around 35-fold, so that with these adjuvants the two formulations were of similar activity. The enhancement ability of these ?Genapol’? surfactants was optimal at lower (5–10 moles) ethylene oxide content. These analogues induced marginally better enhancements of activity than members of a range of nonylphenol ethoxylates (?Arkopal’?), and emulsifiable paraffinic/naphthenic oil (HVI 60E) and a castor oil ethoxylate (?Atlas’? G1281) but were equivalent to a similar series of alcohol ethoxylates (?Dobanol’?) from another source. Varying the alkyl chain length between C₉-C₁₁ and C₁₄-C₁₅ in the ?Dobanol’? series had little effect on their high enhancements of metconazole activity. It was determined from trials varying the application rate of the best alcohol ethoxylates that application rates of 1–1.5 kg ha^?1 were required for maximum activity. This implied the use of high adjuvant/metconazole ratios in one-pack adjuvant-containing formulations. A range of soluble liquid (SL) formulations were prepared with either ?Dobanol’? 23–6.5 or ?Dobanol’? 91-6/metconazole ratios varying from 5:1 to 15:1. There were found to be highly active and were recommended for field testing.     

Evaluation of a vessel-sealing device for laparoscopic granulosa cell tumor removal in standing mares

OBJECTIVE: To describe a laparoscopic technique for granulosa cell tumor removal using a vessel sealing device (LigaSuretrade mark) in standing mares. STUDY DESIGN: Retrospective study. ANIMALS: Eight mares (8-24 years old; weighing, 406-525 kg). METHODS: Before surgery, ovarian size and adjacent body wall thickness was determined by ultrasonography. Mares were sedated and after local anesthesia (inverted L and local infiltration), laparoscopic cannulation was performed without insufflation. The mesovarium was anesthetized and the LigaSure instrument applied to the mesovarium for hemostasis and resection to remove the affected ovary. Mares were hospitalized for 24 hours before discharge. RESULTS: Median ovarian diameter was 10.5 cm (range, 6-14 cm). Median surgery time was 75 minutes (range, 40-180 minutes). Hemostasis was achieved using the LigaSure device in all mares. Median length of the abdominal wall incision made to remove the ovary was 13 cm (range, 5-17 cm); no incisional complications occurred. CONCLUSIONS: The LigaSure vessel sealing device provided adequate hemostasis for removal of larger neoplastic ovaries in standing mares. CLINICAL RELEVANCE: Concerns of ligature placement can be alleviated by use of the LigaSure device and standing laparoscopic technique provides excellent observation of the surgical field ensuring hemostasis.