Knowledge of pesticide exposure levels in farmers is necessary for epidemiological studies and regulatory purposes. In the European pesticide registration process, operators' exposure is predicted ...using the Agricultural Operator Exposure Model (AOEM), created in 2014 by the European Food Safety Authority based on studies conducted by the pesticide industry. We compared operators' exposures during treatment days in the apple-growing industry under non-controlled working conditions and AOEM-predicted values. The dermal exposure of thirty French apple-growers from the CANEPA study when applying two fungicides was measured using body patches and cotton gloves. For each observation, the corresponding exposure was calculated by means of the AOEM, using data recorded about the operator, spraying equipment and personal protective equipment (PPE) used. A significant linear correlation was observed between calculated and measured daily exposures. The model overestimated the daily exposure approximately 4-fold and the exposure during application 10-fold. However, exposure was underestimated during mixing/loading for 70% of the observations when the operator wore PPE. The AOEM did not overestimate exposures in all circumstances, especially during mixing/loading, when operators handle concentrated products. The protection provided by PPE appeared to be overestimated. This could be due to the optimal working conditions under which the "industrial" studies are conducted, which may not be representative of real working conditions of operators in fruit-growing.
•Ranked Set Sampling improves sampling efficiency in fruit growing compared to SRS.•High resolution agricultural sensors help to implement sampling techniques, like RSS.•UAV-based tree canopy ...projected area contributes efficiently to improve fruit load.•Higher image resolution improves the precision of fruit load estimates.
Fruit load estimation at plot level before harvest is a key issue in fruit growing. To face this challenge, two sampling methods to estimate fruit load in a peach tree orchard were compared: simple random sampling (SRS) and ranked set sampling (RSS). The study was carried out in a peach orchard (Prunus persica cv. ‘Platycarpa’) covering a total area of 2.24 ha. Having previously sampled the plot systematically to cover the entire area (104 individual trees or sampling points), both sampling methods (SRS and RSS) were tested by taking samples from this population with varying sample sizes from N = 4 to N = 12. Since RSS requires ancillary information to obtain the samples (ranking mechanism), several proximal and remote sensors already used or recently introduced in agriculture were assessed as data sources. A total of 14 variables provided by 5 different sensors and platforms were considered as potential ancillary variables. Among them, RGB images captured by an unmanned aerial vehicle (UAV), and used to estimate the canopy projected area of individual trees, proved to be the best of the options. This was shown by the high correlation (R = 0.85) between this area and the fruit load, providing RSS with the UAV-based canopy projected area the lowest Coefficient of Error (CE) for a given tree sample size. Then, comparing relative efficiency between random sampling (SRS) and RSS, the latter enables more precise fruit load estimates for any of the considered sample sizes. Interest and opportunity of RSS can be raised from two points of view. In terms of confidence, RSS managed to reduce the variance of fruit load estimates by about half compared to SRS. Sampling errors above the 10% threshold were always produced significantly fewer times using RSS, regardless of the sample size. In terms of operation within the plot, sample size could be reduced by 50%, from N = 10 for SRS to N = 5 for RSS, and this being expected sampling errors less than 10% in practically 70% of the samplings performed in both cases. In summary, fruit growers can take advantage of the combined use of appropriate data (RGB images from UAV) and RSS to optimize sample sizes and operational sampling costs in fruit growing.
Understanding how climate change can affect crop‐pollinator systems helps predict potential geographical mismatches between a crop and its pollinators, and therefore identify areas vulnerable to loss ...of pollination services. We examined the distribution of orchard species (apples, pears, plums and other top fruits) and their pollinators in Great Britain, for present and future climatic conditions projected for 2050 under the SRES A1B Emissions Scenario. We used a relative index of pollinator availability as a proxy for pollination service. At present, there is a large spatial overlap between orchards and their pollinators, but predictions for 2050 revealed that the most suitable areas for orchards corresponded to low pollinator availability. However, we found that pollinator availability may persist in areas currently used for fruit production, which are predicted to provide suboptimal environmental suitability for orchard species in the future. Our results may be used to identify mitigation options to safeguard orchard production against the risk of pollination failure in Great Britain over the next 50 years; for instance, choosing fruit tree varieties that are adapted to future climatic conditions, or boosting wild pollinators through improving landscape resources. Our approach can be readily applied to other regions and crop systems, and expanded to include different climatic scenarios.
Zusammenfassung
Gerade Dauerkulturen, welche über viele Jahre bestehen bleiben, können einen großen ökologischen Wert für Insekten und Spinnentiere darstellen, wenn die negativen Einflüsse durch die ...Bewirtschaftung durch gezielte Maßnahmen minimiert werden. Im Rahmen eines Forschungsprojektes wurde von 2016 bis 2019 an der TH Bingen in Zusammenarbeit mit der Gemeinde Zornheim (Rheinhessen), zwei dort ansässigen Obstbauern, dem Dienstleistungszentrum Ländlicher Raum Rheinhessen-Nahe-Hunsrück (DLR RNH) und der Universität Koblenz-Landau (Campus Koblenz), gefördert durch die Stiftung Natur- und Umwelt Rheinland-Pfalz die Biodiversität von Obstanlagen untersucht. Es wurde eine intensive Erfassung der Insekten und Spinnentiere auf Basis von Individuenzahlen, Verteilung der Tiere auf Großgruppen, Artenzahlen der Käfer (inkl. Rote Liste) und Wanzen, deren Diversität und der sie beeinflussenden Faktoren auf vier Erwerbsobstflächen und einer Streuobstwiese als Referenzfläche untersucht. Mittels eines im Projekt erarbeiteten Bewertungsbogens, wurden die Auswirkungen der fünf Faktorenkomplexe: Sonderstrukturen, Anlagenstruktur, Beschattung, Mahdregime und Einsatz von Pflanzenschutzmitteln erhoben. Die visuelle Darstellung der Einflussfaktoren mittels Netzdiagramm zeigt biodiversitätsbeeinträchtigende Faktoren und ermöglicht so Empfehlungen zur Aufwertung der Biodiversität. Die hier vorgeschlagenen Maßnahmen zielen auf eine Erhöhung der Biodiversität und Minimierung der negativen Auswirkungen der Bewirtschaftung in Erwerbsobstanlagen. Durch eine möglichst große, an die Kultur angepasste Strukturvielfalt soll die Verfügbarkeit von Nistplätzen, Nahrung und Überwinterungsmöglichkeiten für Insekten und Spinnentiere deutlich erhöht werden und damit zur Ausbildung stabiler Populationen führt.
Environmental stress may favour facilitative interactions among plants but whether these interactions are positive for the benefactor and how this depends on stress factors, remains to be determined. ...We studied the effect of beneficiary cover and biomass on reproduction of the benefactor cushion plant Laretia acaulis (Apiaceae) in the central Chilean Andes during three years. Study sites were situated along an elevational gradient at 2600, 2800, 3000 and 3150 m a.s.l. This range comprises a cold‐ and a drought‐stress gradient, with moisture increasing and temperature decreasing with elevation. We studied the effect of natural gradients in beneficiary cover and of experimental cover removal on cushion flower and fruit production. Beneficiary cover had a negative effect on flower production but not on infructescence and fruit densities or fruit weights. A positive effect of beneficiaries on the fraction of flowers converted into fruits was detected for hermaphrodite cushions. The effect of beneficiary cover on flowering was independent of elevation or cushion gender, although these latter factors explained most of the variation. Removing the aboveground parts of the beneficiaries positively affected flowering at 2800 m a.s.l. but not at the other elevations. Our results suggest negative effects of facilitation on L. acaulis flowering, but these are neutralized in fruit production. Surprisingly, this conclusion holds along the entire elevational or stress gradient. This suggests that this system of facilitation is evolutionarily stable and not very sensitive to environmental change. It remains to be tested, however, whether facilitation affects fitness via growth and long‐term survival in these slow‐growing alpine cushions.
There is a widespread recognition that above‐ and below‐ground organisms are linked through their interactions with host plants that span terrestrial subsystems. In addition to direct effects on ...plants, soil organisms such as root herbivores can indirectly alter interactions between plants and other community members, with potentially important effects on plant growth and fitness. We manipulated root herbivory by Acalymma vittatum in Cucumis sativus to determine indirect effects on arbuscular mycorrhizal fungi, leaf herbivory, the leaf pathogen downy mildew and pollinators. We also manipulated pollen receipt by plants to determine whether root herbivory reduced plant reproduction through changes in pollinator visitation. Overall, root herbivory had strong net negative effects on plant growth and fitness, with 34% reductions in both leaf and fruit production by high root damage levels relative to control, despite reduced infection by downy mildew. High root herbivory also reduced floral visitation by 39%, apparently due to lower flower production, as flower size and scent were unaffected. Above‐ground herbivory was not affected by root herbivores. Although root herbivory reduced pollinator visits, pollen receipt manipulations had no effect on fruit set, indicating that reduced pollinator service did not affect plant reproduction. Synthesis. Root herbivory had indirect effects on a range of community members, including mutualists and antagonists both above‐ and below‐ground. Although reduced pathogen infection associated with root herbivory would be expected to benefit plants, root herbivory had an overall strong negative effect on plant growth and reproduction, indicating that direct negative effects over‐rode any potential indirect benefits.
In order to eliminate the negative effects of conventional agriculture on human health and the environment, organic agriculture and good agricultural practices have become widespread in recent years ...and researches on this has gained importance. The aim of this research is to determine the opinions of farmers engaged in conventional fruit farming on organic agriculture and good agricultural practices in Zonguldak province located in the Blacksea Region of Turkey, and their thoughts on the transition to these production systems in the future. Survey data consist of questionnaires conducted with 125 fruit farmers engaged in conventional agriculture. According to the results of the research, the rate of farmers who think that chemical fertilizers are used in organic agriculture is 12.00%, and the rate of those who think that pesticides are used is 46.40%. In good agricultural practices, 25.60% of the farmers think that chemical fertilizers are not used, and 12.80% of them think that pesticides are not used. These results show that the farmers do not have enough knowledge about organic agriculture and good agricultural practices and that they are not sufficiently aware of the application principles of these systems. While the rate of farmers who intend to switch to organic agriculture is 28.00%, this rate is only 8.80% in good agricultural practices. The adoption of organic agriculture and good agricultural practices by farmers depends on the profitability of these farming systems compared to conventional agricultural products. For this purpose, especially considering the increasing input costs in recent years, the supports given to organic agriculture and good agricultural practices should be revised.
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