Spiders act as one of the major predators among arthropods in agroecosystems and are crucial to the control of pest densities. As they are almost exclusively predators, they have developed a number ...of hunting strategies, which have consequently impacted their complex trophic interactions. The development of molecular biology methods for environmental DNA analysis has made it easier to analyze such complex trophic networks. In order to ascertain the trophic interactions of spiders, a sampling of spider species was carried out in two olive groves in Zadar County, Croatia, under integrated and ecological pest management. To construct the trophic networks of spiders, we performed DNA metabarcoding. The combined general and spider-excluding primers were able to recognize prey from 12 distinct orders in the guts of the 57 spiders. According to our results, spiders have a complex trophic network that exhibits seasonal and site-specific variations. The results obtained from both sites having different pest management also confirmed that spiders consumed phytophagous insects in the highest ratio, including some important pests, in comparison to other prey and that management and guild type had an impact on the predation of phytophagous insects.
Apple is one of the most important economic fruit crops in the world. Despite all the strategies of integrated pest management (IPM), insecticides are still frequently used in its cultivation. In ...addition, pest phenology is extremely influenced by changing climatic conditions. The frequent spread of invasive species, unexpected pest outbreaks, and the development of additional generations are some of the problems posed by climate change. The adopted strategies of IPM therefore need to be changed as do the current monitoring techniques, which are increasingly unreliable and outdated. The need for more sophisticated, accurate, and efficient monitoring techniques is leading to increasing development of automated pest monitoring systems. In this paper, we summarize the automatic methods (image analysis systems, smart traps, sensors, decision support systems, etc.) used to monitor the major pest in apple production (Cydia pomonella L.) and other important apple pests (Leucoptera maifoliella Costa, Grapholita molesta Busck, Halyomorpha halys Stål, and fruit flies—Tephritidae and Drosophilidae) to improve sustainable pest management under frequently changing climatic conditions.
The Western corn rootworm (WCR),
LeConte, has been a serious quarantine pest to maize in Europe since the mid-1990s. The integrated pest management of WCR requires an accurate knowledge of the ...factors that contribute most to risks of crop damage, as well as knowledge of effective area-wide strategies based on agronomic measures, such as crop rotation. In Italy and Croatia, agronomic and cultural factors in fields damaged by WCR were evaluated through a long-term survey. Based on the survey results, high-WCR densities contribute most to risks of damage to maize. Extensive field research in north-eastern Italy compared large areas of continuous maize production with areas under different crop rotation systems (i.e., a structural one with one-time maize planting in a three-year rotation and a flexible one with continuous maize planting interrupted when beetle populations exceed the threshold). The objective was to evaluate the effectiveness of different rotation regimes as possible best practices for WCR management. Captures of beetles in yellow sticky traps, root damage, larval densities, and damage to maize plants (e.g., lodging) were assessed at the center of each area. The results demonstrated the both structural and flexible crop rotation systems were effective strategies for maintaining WCR below damage threshold densities without the need for insecticides.
Olive (Olea europaea L.) is a Mediterranean fruit crop that requires irrigation to achieve optimal yield and quality. Irrigation practices and damage of olive fruit curculio (Rhodocyrtus cribripennis ...(Desbrochers, 1869)), a pest of olive fruit, may be an important factor in determining the stage of fruit maturity, one of the main indicator of of fruit quality. The aim of this paper is to determine how different practices, through the amount and frequency of irrigation, with presence of olive fruit curculio, affect the maturity index of olive, variety ‘Coratina’. The research was conducted on 24 olive trees at two locations in Zadar County: Žman (Dugi otok) and Novigrad. Irrigation was performed with a drip system with four variants in three replicates: K (0%) rainfed olives; T1 (PP) irrigation set according to grower experience; T2 (SAN) irrigation set according to evapotranspiration and olive phenology, at up to 80% of field capacity and T3 (100%) where 100% of calculated evapotranspiration was added. Soil analysis determined the field capacity, and evapotranspiration was read from the Pinova™ meteorological station. Harvests was conducted in October 2020 and 2021. For determination of olive fruit curculio infestation and maturity index, 100 fruits per sample were harvested. By processing the data with one-way analysis of variance (ANOVA) and return test (Tukey), the significant effect of irrigation practices on the olive fruit maturity index by treatments, years and locations, single and interdependent, was determined. No effect was found between the presence of olive fruit curculio and the maturity index.
Fluctuating asymmetry (FA) is used in assessing the effect of environmental stress on the development stability of individuals by measuring small random deviations from perfect bilateral symmetry. ...Here, we checked for FA on two predatory carabid beetles, Pterostichus melas and Poecilus koyi, in order to evaluate species response to agricultural practices within Mediterranean agroecosystems, as well as FA as a method. The samples were collected in vineyards and olive groves, both under integrated pest management (IPM) and ecological pest management (EPM), and in pristine habitats in the Mediterranean region of Croatia. Geometric morphometrics (GMMs) were used to analyze the pronotum and abdomen shape variations and left–right asymmetries of each population. In respect to the FA measurements, analyzed species responded differently, with P. koyi displaying a lower intensity of FA than P. melas. On the other hand, P. melas beetles from vineyards showed a higher intensity of FA compared with populations from pristine habitats and olive groves. Accordingly, FA pointed out olive groves as potentially less adverse habitats to predatory carabids, keeping in mind the different levels of asymmetry between the two species. Our study singled out P.melas as a more suitable species for further research, in the effect that different agricultural practices can have their impact on non-target invertebrates analyzed by measuring the FA.
The pear leaf blister moth is a significant pest in apple orchards. It causes damage to apple leaves by forming circular mines. Its control depends on monitoring two events: the flight of the first ...generation and the development of mines up to 2 mm in size. Therefore, the aim of this study was to develop two models using artificial neural networks (ANNs) and two monitoring devices with cameras for the early detection of L. malifoliella (Pest Monitoring Device) and its mines on apple leaves (Vegetation Monitoring Device). To train the ANNs, 400 photos were collected and processed. There were 4700 annotations of L. malifoliella and 1880 annotations of mines. The results were processed using a confusion matrix. The accuracy of the model for the Pest Monitoring Device (camera in trap) was more than 98%, while the accuracy of the model for the Vegetation Monitoring Device (camera for damage) was more than 94%, all other parameters of the model were also satisfactory. The use of this comprehensive system allows reliable monitoring of pests and their damage in real-time, leading to targeted pest control, reduction in pesticide residues, and a lower ecological footprint. Furthermore, it could be adopted for monitoring other Lepidopteran pests in crop production.
The Mediterranean is characterised by high biodiversity and numerous endemic species. These species are not only present in natural habitats, but also inhabit areas under human influence, such as ...agricultural lands. In the biodiversity assessment of Mediterranean vineyards and olive orchards within Zadar County, in Croatia, we identified eight endemic species with Mediterranean distribution, six with a Balkan Peninsula distribution, four with Dinaric Alps distribution and three species rare and endangered in Europe. Alongside these species, we have recorded five new species for Croatian fauna, many of those identified by combining morphological characteristics and the DNA barcoding tool. Araneae and Coleoptera contributed the highest number of endemic species and groups with new record were the following: Coleoptera, Diptera and Araneae. Compared to other sites, an olive orchard with ecological pest management (EPM), surrounded by natural ecosystems, had the highest ratio of endemic and rare species. Our findings emphasise that agricultural lands in the Mediterranean can be habitats for endemic and rare species and that future biodiversity research of these habitats is highly important, to monitor potential biodiversity changes and motivate future species and ecosystem conservation.
Olive groves in the Mediterranean may lose production sustainability because of their vulnerability to climatic change. Irrigation is an important measure that could significantly affect fruit yield, ...olive fruit fly infestation, and oil characteristics. The aim of paper was to compare the regulated deficit irrigation with different water management practices, in consecutive years, in two locations in Zadar County (Croatia), affecting fruit morphology, olive fruit fly infestation, and quantity and quality of the extracted Coratina cultivar oil. Treatments, namely C—rainfed, T1—deficit irrigation (produce’s practice), T2—regulated deficit irrigation, and T3—full irrigation (100% ECTO), were established. Irrigated treatments had a positive effect on all morphological characteristics of the fruit. The pulp mass, independently of the year, increased in irrigated treatment (ranging from 1.04 to 1.65 in C to 2.25 and 2.30 in the irrigated treatments) and resulted in a higher oil content on a fresh weight basis (ranging from 16.39% to 17.85% in C to 19.48% to 23.26% in the irrigated treatments). However, fruit yield per tree was only location-dependent. When olive fruit fly presence was high, fruit infestation was greatest in the irrigated compared to the rainfed treatment. According to quality parameters, all oils were classified as EVOO. Individual phenols were influenced by irrigation, while the composition of fatty acids was more influenced by location than treatment. The sensory characteristics of the resulting oil were slightly reduced compared to rainfed treatment. The results indicate that regulated deficit irrigation benefits water use sustainability without compromising the quality of the oil.
For the first time the effects of different sampling periods and their interaction with five major autochthonous Croatian Istrian olive cultivars and the Italian cultivar ‘Leccino’ on the quantity ...and composition of olive leaf phenolic compounds and mineral nutrients were investigated. For that purpose, olive leaves were sampled in two collecting periods, in October and March, coinciding with the harvesting and pruning periods, respectively. All selected cultivars had a higher oleuropein leaf content in the pruning collecting period, with the highest levels noted for the ‘Leccino’ and ‘Buža’ cultivars. Cultivar significantly affected almost all the investigated phenols, with higher concentrations of these valuable compounds in the pruning than in the harvesting period. Differences observed in leaf mineral composition were closely related to the differences in phenolic profiles and were significantly affected by genotype. Some of the studied mineral nutrients, such as P, Cu and B, were found to be significantly correlated with the most abundant olive leaf phenolic compounds, oleuropein and verbascoside.