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Kiwifruit has a strong dependence on insect pollinators, and yet the relatively low attractiveness of kiwi flowers to European pollinators may lead to deficits in production. In Italy, due to the scarce efficacy of the honey bee in pollinating kiwifruit, the most used strategy to mitigate this issue is artificial pollination with mass-produced pollen, which incurs high costs and increases the risk of disease; alternative strategies are thus direly needed. The aims of this study are i) to quantify pollination deficit and pollinator contribution to kiwifruit production and quality, and ii) to investigate the release of red mason bees Osmia bicornis (L.) (synonym Osmia rufa) (Hymenoptera Megachilidae) and the use of flower strips (supporting both wild pollinators and the released red mason bees) as strategies for the improvement of kiwifruit pollination. Through manipulative experiments in 3 golden kiwifruit orchards in Northern Italy, we verified that kiwifruit production in the area was significantly improved by insect pollinators, but also suffered from pollination deficit, with average reductions of 9% in fruitlet set, 15% in final fruit set, and 30% in seed number. Our findings confirmed successful population establishment of managed O. bicornis in most sites, and analyses of pollen collected in their provisions indicated that these bees effectively gathered kiwi pollen. While the presence of O. bicornis had limited but statistically significant positive effects on fruit production and quality, the introduction of flower strips had a distraction effect on O. bicornis and other pollinators, leading to some negative consequences on the target crop. This suggests a need for careful management of floral resources to balance the benefits of supporting pollinator populations with the goal of maximizing kiwifruit production; at the same time, the introduction of managed pollinators such as O. bicornis might be especially beneficial to this crop in agroecosystems that are poor in alternative flower resources. [ABSTRACT FROM AUTHOR]

Simple Summary: Botanical insecticides and soaps are frequently considered environmentally friendly and compatible with the biological control of pests because of their purported higher selectivity towards beneficial insects when compared with synthetic insecticides. These claims are, however, only partially backed up by the scientific literature, thus justifying a case-by-case evaluation of botanical insecticides. Here, we tested the efficacy of five botanical insecticides and soaps belonging to different categories (pyrethrins, essential oils, crude plant extracts and insecticidal soaps) on the important aphid pest Myzus persicae (Sulzer) and their selectivity towards two of its biological control agents, the ladybird beetle Propylea quatuordecimpunctata (L.) and the parasitoid Aphidius colemani (Dalman). The pyrethrin-based product was the most effective against aphids but more detrimental to ladybird beetle larvae when compared to the alternatives. Some detrimental effects on ladybird beetles were also caused by white thyme essential oil, sweet orange essential oil and Marseille soap. Additionally, although pyrethrins have a broader spectrum of insecticidal activity compared to most botanical insecticides, they had no significant adverse effect on adult ladybird beetles and parasitoids within aphid mummies, similar to most of the other tested natural products. Botanical insecticides and soaps are frequently proposed as environmentally safer alternatives to synthetic insecticides. However, the efficacy and selectivity of these products are often only partially supported by empirical evidence. Here, we tested the effectiveness of five botanical insecticides, belonging to different categories, on the green peach aphid Myzus persicae (Sulzer) and their selectivity towards two natural enemies, the ladybird beetle Propylea quatuordecimpunctata (L.) and the parasitoid Aphidius colemani (Dalman). White thyme essential oil (EO), sweet orange EO, crude garlic extract and Marseille soap were tested and compared with a pyrethrin-based commercial product. Both direct spray assays and residual contact assays on treated cabbage leaf disks were carried out. The tested products had low efficacy against aphids when compared to pyrethrins but were in general less detrimental to ladybird beetle larvae, meaning that if applied against other pests, they have a lower chance of harming this agent of aphid biocontrol. Some of the products (soap, orange EO) did, however, show direct exposure toxicity toward ladybird larvae, and thyme EO had extensive phytotoxic effects on cabbage leaves, possibly indirectly leading to higher mortality in ladybird adults. These results underline the necessity for case-by-case evaluations of botanical insecticides. [ABSTRACT FROM AUTHOR]

Measuring habitat specialisation is pivotal for predicting species extinctions and for understanding consequences on ecosystem functioning. Here, we sampled pollinator and natural enemy communities in all major habitat types occurring across multiple agricultural landscapes and used species–habitat networks to determine how habitat specialisation changed along gradients in landscape composition and configuration. Although it is well known that landscape simplification often causes the replacement of specialists with generalists, our study provided evidence for intraspecific variation in habitat specialisation, highlighting how a large number of arthropod species adapted their way of selecting habitat resources depending on the landscape structure. Groups with higher diet specialisation and limited foraging flexibility appeared to have a reduced ability to respond to landscape changes, indicating that some arthropod taxa are better able than others to adapt to an increasingly broad set of resources and persist in highly impacted landscapes. [ABSTRACT FROM AUTHOR]

Climate change is increasingly requiring the adoption of both climate-resilient alternative crops and sustainable management practices. Millets and sorghum are increasingly recommended as alternatives to maize in addressing these issues, yet there are no studies comparing the environmental impacts of food-crop millets and sorghum with maize, under sustainable management in Mediterranean area. The present study examined for the first time the environmental and economic impacts, as well as agronomic performances, of rainfed cultivated proso millet, sorghum and maize over a three-year period under challenging climatic conditions in Emilia-Romagna region, Italy. Different kinds of trials were realized during three years of experimentation in one location in Ravenna province. The first trial aimed to compare proso millet, sorghum and maize agronomical performances and water use efficiency in a low-input system. The second trial aimed to compare soil fertility and biodiversity impacts of two different agronomical management systems (low-input and high input) for the summer crops previously described. Soil basic fertility parameters were monitored and ground dwelling arthropods were collected and analyzed using pitfall traps. The last trial of this study intended to evaluate the environmental and economic performances of the previous cereal crops cultivated in the low-input and high-input systems, applying the Life Cycle Assessment (LCA) and the Life Cycle Costing (LCC) methodologies. Both organic sorghum and millet showed high potential as viable summer-crop alternatives, not only to organic maize, based on yield, water use efficiency, disease tolerance and weed competition, but also to conventional maize, based on reduced environmental and economic impacts. Positive land impacts including improved beneficial arthropod abundances and preserved soil fertility were evident under organic management. In fact, the comparative LCA and LCC, carried out with primary data from conventionally cultivated maize and sorghum within central-north Italy and the organic experimental field under investigation, showed that the Global Warming and Eutrophication Potential, were comparable between the organically cultivated crops and significantly lower than conventional maize and sorghum. The results highlighted the potential of sorghum and millet cultivation as rainfed summer-crop alternative to maize in climate-change context, especially in low-input agronomical systems. In particular, under rainfed, organic management over three years, proso millet yielded consistently. Under the sustainable practices of the present study, proso millet outperformed maize for yield and WUE stability, as well as potential costs saved, related to the production amount per unit area and potential revenue. • Millets and sorghum are maize alternatives under challenging climatic conditions • Under low-input management, millet outperformed maize for yield and WUE stability • Low input system improved beneficial arthropod abundances and soil fertility • In organic systems, sorghum and millet showed higher revenue compared to maize [ABSTRACT FROM AUTHOR]