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Context Landscape simplification is a main driver of insect decline, threatening crop pollination services. Changes in functional features in simplified agroecosystems may impact the abundance of wild pollinators. Objectives Here, we studied whether different pollinator groups based on life-history are differentially associated to landscape features, and how this affects crop pollination service delivery. Methods Using window traps in a highly simplified agroecosystem, we surveyed pollinator abundances and diversity associated with: (1) bare fence-lines separating pastures (control), (2) conifer hedgerows (3) farm gardens of diverse exotic plant species (4) effluent-ponds, (5) newly established native-plantings, (6) gorse (Ulex europaeus) hedgerows and (7) open water channels across six to twelve dairy farms. We also measured pollination service delivery to potted pak choi (Brassica rapa) plots near features 1–5 on six farms. Results Pollinators at gardens, native-plantings, and effluent-ponds delivered significantly more pollination service than at bare fence-lines, with flies being more effective pollinators than bees at all features assessed. Taxa delivering the service also differed across features. The native bee Lasioglossum sordidum delivered more pollination at garden and native-planting features than at other features, drone flies (Eristalis tenax) contributed the majority of pollination service at effluent-ponds and bare fence-lines, while calliphorid flies contributed most pollination at conifer hedgerows. Conclusions Conversion of functional features to bare fence-lines negatively affects on-farm pollinator diversity and its service to crop plants. However, farmers can benefit from enhancing features containing diverse plant species that support non-bee and bee species proven to deliver measurable crop pollination services.

As agricultural intensification affects global environmental change, a redesign of our food production systems towards practices that replace external inputs with inbuilt ecosystem services is needed. Specifically, human-induced changes to biogeochemical flows of nitrogen (N) cycling exceed the proposed planetary boundaries, highlighting a priority area for reducing nutrient inputs in agricultural production systems. A new understanding of nutrient interactions in the complete agroecosystem will allow us to better predict and mitigate the consequences of anthropogenic environmental changes compared with a reductionist approach. Here, we review for the first time system-level nutrient interactions, particularly N, in perennial horticulture using high-producing kiwifruit and apple crops grown in New Zealand as a basis to identify critical knowledge gaps and prioritize new research. The major points identified are (1) current nutrient guidelines are from the 1980s to the early 2000s and do not take into account substantial production changes since that time; (2) few studies construct complete nutrient budgets of all sources and losses; (3) nutrient loss estimates are generally low relative to those from other agricultural land uses; (4) there is a lack of studies which address nutrient interactions between above- and below-ground food webs in perennial horticultural crops; (5) there is contradictory literature where fertilizer has been found both to increase and to decrease plant chemical signaling and defense mechanisms. New tools are emerging to improve orchard nutrient management, including advances in fertilizer application techniques, new methods to monitor plant and soil nutrients, and utilizing genetic variability to breed cultivars with improved nutrient use efficiency. To reduce adverse nutrient effects on the environment, new research is needed, addressing the relationships between carbon and nutrients and nutrient demands in modern fruit cultivars and growing systems; the nutrient balance for perennial horticultural crops considering all inputs and outputs; and interactions of the above- and below-ground nutrient flows in orchard food webs.

The drone fly (Eristalis tenax) pollinates many crops and is found almost worldwide. Its successful management as a field-crop pollinator would provide an additional option to augment bee pollination. We reviewed literature to assess their management potential. A literature search was conducted for information on drone-fly abundance across New Zealand crops, pollinator effectiveness, lifecycle-requirements and potential for mass rearing. Relevant literature was then evaluated to assess the feasibility, benefits and limitations of their management. Eristalis tenax is a proven pollinator of pak choi (Brassica rapa spp. chinensis), kiwifruit (Actinidia deliciosa) and onion (Allium cepa), and visits the flowers of several more crops in New Zealand. It readily completes its lifecycle under laboratory conditions when reared on various organic materials. No reviewed studies were identified that showed successful management of populations for the purpose of field-crop pollination. Key challenges for their management as field-crop pollinators include: being able to mass rear them at an appropriate scale; retaining numbers within targeted areas in the field; and ensuring their use does not significantly impact on non-target species and land-user interests.

Protecting, establishing and managing biodiverse semi-natural habitats is one strategy within the concept of ecological intensification of agriculture that supports insect pollinator abundance and diversity in agroecosystems. However, without accounting for species-level relationships between insects, crops and non-crop vegetation, diverse semi-natural habitats may not lead to improved crop pollination, and could create pest reservoirs. Possibly thousands of non-bee insect species contribute to global crop pollination, but research has largely focussed on bees. Thus, key information to best manage habitats that target wider crop pollinator diversity and abundance is lacking. We demonstrate the concept of designing mixed species native plantings (a type of semi-natural habitat) based on plant-insect interactions to increase abundance and diversity of non-bee and bee crop pollinators in an intensively managed agricultural landscape. We used existing refereed and grey literature to identify and anticipate interactions between pollinators, natural enemies and pests with native plants and crop species to design and establish plantings on three farms. We anticipated the designed plantings would support 21 pollinating species, 20 of which were verified in observational surveys 5 years post-establishment. While anticipated bee–plant species interactions were largely confirmed, actual networks of the non-bee pollinators, were larger and more complex than expected, indicating the plantings were particularly effective in supporting these interactions. Most immature life-stages of non-bee pollinators were not directly supported by plantings and separate strategies should consider larval requirements. Presenting the plant-pollinator networks to relevant industries has been a powerful tool for incentivising their support for designed habitats on farms.

Protective covers (i.e., glasshouses, netting enclosures, and polytunnels) are increasingly used in crop production to enhance crop quality, yield, and production efficiency. However, many protected crops require insect pollinators to achieve optimal pollination and there is no consensus about how best to manage pollinators and crop pollination in these environments. We conducted a systematic literature review to synthesise knowledge about the effect of protective covers on pollinator health and pollination services and identified 290 relevant studies. Bees were the dominant taxon used in protected systems (90%), represented by eusocial bees (e.g., bumble bees (Bombus spp.), honey bees (Apis spp.), stingless bees (Apidae: Meliponini)) and solitary bees (e.g., Amegilla spp., Megachile spp., and Osmia spp.). Flies represented 9% of taxa and included Calliphoridae, Muscidae, and Syrphidae. The remaining 1% of taxa was represented by Lepidoptera and Coleoptera. Of the studies that assessed pollination services, 96% indicate that pollinators were active on the crop and/or their visits resulted in improved fruit production compared with flowers not visited by insects (i.e., insect visits prevented, or flowers were self- or mechanically pollinated). Only 20% of studies evaluated pollinator health. Some taxa, such as mason or leafcutter bees, and bumble bees can function well in covered environments, but the effect of covers on pollinator health was negative in over 50% of the studies in which health was assessed. Negative effects included decreased reproduction, adult mortality, reduced forager activity, and increased disease prevalence. These effects may have occurred as a result of changes in temperature/humidity, light quality/quantity, pesticide exposure, and/or reduced access to food resources. Strategies reported to successfully enhance pollinator health and efficiency in covered systems include: careful selection of bee hive location to reduce heat stress and improve dispersal through the crop; increased floral diversity; deploying appropriate numbers of pollinators; and manipulation of flower physiology to increase attractiveness to pollinating insects. To improve and safeguard crop yields in pollinator dependent protected cropping systems, practitioners need to ensure that delivery of crop pollination services is compatible with suitable conditions for pollinator health.

New Zealands increasing trade and tourism with Asia and especially China brings with it the need to understand the biosecurity risk to New Zealand from these countries This study compared the number of articles on two Chinese horticultural pests and two Chinese horticultural plant pathogens both of biosecurity relevance for New Zealand which were extracted using webbased searches conducted on two international and three Chinese databases There were up to 35 times more articles found in Chinese databases searched with Chinese characters than found in international databases searched with Latin script The quality of information from the articles in any of these databases was not examined Based on these results it would be prudent to explore further the information found in Chinese articles stored in Chinese databases to determine their relevance to New Zealands biosecurity system Searching Chinese databases with Chinese characters in combination with the more usual searches in international databases might ensure a more comprehensive coverage and could help to reduce the biosecurity risk to New Zealand in the future

Macadamia nuts are a valuable culinary resource, but yields can vary substantially between varieties, orchards and seasons. The nuts are harvested from commercial varieties derived from two endemic Australian tree species; Macadamia integrifolia Maiden & Betche and Macadamia tetraphylla L.A.S. Johnson. While some aspects of crop management for this relatively new crop are well known and generally well applied—including variety selection, irrigation and pesticide application—progress towards increasing quantity and reliability of yield has proven elusive. Hand pollination studies indicate that inadequate cross pollination contributes to low nut set and thus low yield. Typically just 0.3% of flowers develop into harvestable nuts. Lack of nut development after flowering and early abscission are indicators of poor fertilisation of the ovule. Honey bees ( Apis mellifera Linnaeus, 1758) are routinely reported as the most common insect visitor to macadamia flowers, and are widely regarded as the most important agent for transferring pollen between flowers. Stingless bees, beetles, flies and birds also visit flowers and have been considered as pollinators. In this review, we aim to collate what is currently known about the pollination of macadamia varieties, assess the factors that may hinder effective pollination and subsequent yield, and identify opportunities to improve both pollination and yield in commercial macadamia orchards.