Habitat manipulation – as a pest management tool in vegetable and fruit cropping systems, with the focus on insects and mites

Today, there is increasing interest among Swedish growers in biological diversity within the agricultural landscape. Many scientific studies have highlighted the services performed by beneficial organisms, which can help to improve the quantity and quality of crops. One tremendously important ecosystem service is biological control of pest insects and mites. The question is what growers can actually do to increase the abundance and diversity of natural enemies and whether this will have an impact on the pest population and, more importantly, on yield and quality of the crop. Another question is whether biodiversity is always positive for growers or whether there are negative aspects that should be dealt with. These relevant questions are addressed in the present report, the aim of which is to enlarge the current knowledge base on how to improve conditions for natural enemies, so-called habitat manipulation, within annual vegetable crops and perennial apple cropping systems. However, our aim was not to conduct a complete review of all available literature, but instead to select studies that may be of particular value for advisors and growers. We also chose to include the outcomes of a workshop on increasing diversity in apple orchards and interviews with advisors and vegetable growers to investigate the attitude and state of knowledge on habitat manipulation in Sweden today. We focus on natural enemies, arthropod pests and practices applied at field scale, and therefore exclude applications developed for greenhouse crops. Our hope is that advisors and interested growers in particular will find this report relevant and rewarding

Konceptuell modell Övervakningsmetoder för naturliga fiender i relation till skadegörarförekomst, biologi och metodernas styrkor och svagheter

A poster showing the relationship between major pests, key natural enemies and monitoring methods for natural enemies over a growing season. Based on field research in south Swedish apple orchards over several years

Attract, reward and disrupt: responses of pests and natural enemies to combinations of habitat manipulation and semiochemicals in organic apple

The widespread use of pesticides along with the simplification of the landscape has had undesirable effects on agroecosystems, such as the loss of biodiversity and the associated ecosystem service biological control. How current production systems can be remodelled to allow for a re-establishment of biological pest control, while preserving productivity, is a major challenge. Here, we tested whether a combination of tools could augment or synergize biological control of insect pests in apple (Malus domestica), comprised of a tortricid pest complex, a geometrid pest complex and the rosy apple aphid. The tools aimed at disrupting mating behaviour of multiple pest species (multispecies mating disruption, "Disrupt", MMD), attracting natural enemies (a blend of herbivory-induced volatiles, "Attract", A), or providing refuge and rewards for a diverse insect community (perennial flower strip, "Reward", R) over a 3-year period. Suction samples were consistently richer in generalist predators but not in parasitoids when multiple tools including MMD + A + R or MMD + A were employed. In addition, lepidopteran pest levels were significantly lower in these plots than in MMD or MMD + R at the end of the 3-year experiment. This was, however, not reflected in survival of artificially established aphid colonies. Our data indicates that multiple, complementary tools can greatly enhance natural enemy level, but also that long-term implementation is needed to fully realize the augmentatory or synergistic potential of complementary components and restore biological control as an ecosystem service of practical relevance

Manuel des méthodes simplifiées pour suivre la biodiversité fonctionnelle en vergers de pommiers

Ce manuel a été conçu dans le cadre du projet européen Ecoorchard financé par CORE ORGANIC. Il a été pensé pour aider les arboriculteurs à observer par eux-mêmes les dynamiques d'auxiliaires dans leur verger, en fonction de leurs pratiques culturales et de leurs aménagements. Quatre méthodes simples sont proposées. Des grilles de notation sont également incluses

Booklet of simplified methods for the monitoring of functional biodiversity in organic orchards

This booklet has been conceived in the frame of the Ecoorchard project, funded under CORE ORGANIC. It is designed to help farmers in using simple methods to assess functional biodiversity in their orchards. Four methods have been chosen : visual observation, beating, cardboards, sentinel preys. Notation grids are also integrated in order to facilitate farmers involvement

Predatory arthropod community composition in apple orchards: Orchard management, landscape structure and sampling method

Studies on predatory arthropods in agricultural areas seldom include Diptera other than hoverflies, partly because common sampling methods are less effective for capturing species that easily fly off when disturbed. To study the effect from this bias when describing the predator community, we compared traditional beat sampling of branches and suction sampling for describing the community of predatory arthropods in Swedish apple orchards, both organic orchards and orchards using integrated pest management (IPM). Our results indicate that the proportion of both predatory dipterans and parasitic hymenopterans increase dramatically when using suction sampling (Diptera: 32% vs. 20%, Hymenoptera: 25% vs. 7%). In fact, predatory dipterans were the most abundant predatory group when using suction sampling, in contrast to beat sampling where spiders were the most abundant group. One group of predatory flies that was particularly rich in both species and individuals in the surveyed apple orchards was dance flies in the family Hybotidae. Even though the bias of sampling method was evident, it was encouraging that the method choice did not affect the conclusions concerning management on predatory arthropod communities. With both methods, dipteran and coleopteran predators were more abundant in organic apple orchards whereas opilionids were more abundant in orchards managed according to IPM. The inclusion of landscape variables further indicated effects of landscape diversity and of deciduous forest cover, but the response varied in sign between predatory groups. Whereas both Coleoptera and Heteroptera were more abundant in orchards surrounded by more complex landscapes (high landscape diversity and/or high deciduous forest cover), spiders, opilionids and dipterans were rather less abundant in these orchards. To conclude, our study points to the potential importance of predatory dipterans in apple orchards, and we highly recommend future studies of arthropod predators in apple and other crops to actively include predatory Diptera

PRÆSENTATIONSHÅNDBOG MED ENKLE METODER TIL OPGØRELSE AF FUNKTIONEL BIODIVERSITET I ØKOLOGISKE FRUGTPLANTAGER

Purpose of the monitoring methods: Familiarize producers with the simplified observation of beneficials Raise the awareness of producers to the natural regulations that are occurring in their orchards Engage the adaptation of plant protection practices in order to optimize these regulations When possible, observe the effect on biological control of agroecological infrastructures implemented in the orchard over space and time The state of the art does not provide threshold values of natural enemies as decision support for immediate pest management measures as pesticide application Purpose of evaluation of monitoring techniques - Co-define the criteria that have to be met so that the methods can be used by the farmers and advisors - Refine the proposed protocols for the different methods : Determine the respective advantages and the flaws of monitoring methods and their protocols and refine the protocols accordingly - Bring out and build on the assessment of the farmers about the methods Method : Four monitoring methods have been selected by the EcoOrchard project after literature review and initial testing. Each producer in the EBIONET network is offered to choose one or more monitoring method among the four presented in this booklet and additional methods suggested by the stakeholders during the national workshops. The list with the additional methods are in the report of the workshop, the organizers should be available to provide protocols for these methods (for that purpose, it is possible to contact [put the name and contact of the national coordinator]). The producers and advisors will apply the method(s) in the orchards they work in. The purpose is to familiarize with the monitoring of the main beneficials and to evaluate how user-friendly the methods and instructions are. The method can be tested in several ways : By comparing the results of a monitoring nearby an agroecological infrastructure (AEI - e.g. a composite hedge, a flower strip, a water body, nest boxes etc) with the results of a control monitoring distant from any AEI (cf. figure below), In an orchard which is managed with an agroecological practice, like reduced mowing, In order to follow the temporal evolution of arthropods at key moments of the season, like the arrival or the peak of abundance of an insect (according to the life cycles of the aimed populations, cf. protocoles), To monitor the impact of a treatment on arthropods (observation before and after the treatment) The chosen method will be used according to a sampling plan described in the sheets below. If the methods are used to compare the presence of beneficials between two treatments (two separate zones of the same orchard or two different orchards), one being agroecological and the other being a control, it is important to make sure that the control is distant enough from any agroecological infrastructure that could confuse the result. Ideally the control should be at 50m distance of any AEI. Many factors impact the presence of insects in a plot (e.g. farming practices, landscape, variety and age of the trees), it is important to take this into account when comparing the results of monitoring that have been performed in different orchards

Using flower strips to promote green lacewings to control cabbage insect pests

Habitat management improves biological control by increasing the abundance and fitness of natural enemies through the provision of floral resources along field edges or between crops. Among the natural enemies reliant on flower resources, green lacewings often stand out due to their abundance, predation capacity and polyphagy. We evaluated the impact of tailored flower strips on the enhancement of natural enemies, especially green lacewings, in three organic cabbage (Brassica oleracea) farms in Southern Sweden. Insects were sampled from the flower strips, and cabbage pests and predators were visually recorded in the crop. In a laboratory assay, the pollen feeding preferences of Chrysoperla carnea (Stephens, 1836) were evaluated in a dual-choice test. The pollen consumed by the Chrysopidae was extracted from laboratory and field specimens, then quantified and identified. Flower strips were found to attract predators and parasitoids, whose abundance increased as flowers bloomed. Cabbage plants next to the flower strips showed lower pest infestation as compared to cabbage plant control, although no significant differences were observed in the number of predators. Chrysopidae used flower strips as feeding, reproduction and shelter sites and mainly consumed pollen from Phacelia tanacetifolia Benth. Under laboratory conditions, C. carnea showed a preference for P. tanacetifolia and Coriandrum sativum L. pollen over Borago officinalis L. and Fagopyrum esculentum Moench. We show that tailored flower strips could be an efficient tool for enhancing beneficial arthropods and should be considered in integrated pest management for cabbage crops

Innovative design and management to boost functional biodiversity of organic orchards : the ECOORCHARD project

Orchards are perennial cultures, and, especially in organic fruit production it is essential to design and manage orchards in a way which favours beneficials such as insect predators and parasitoids over pests and diseases. As landscape-dominating crops their management affects overall biodiversity in the agricultural landscape. Increasing plant biodiversity and habitats in such a way that beneficials are favoured is called Functional Agro-Biodiversity (FAB). The value of FAB for reducing pesticide use in fruit production is generally acknowledged, and many growers try to increase it. However, they lack situation-specific information about how to drive and assess biodiversity to optimize FAB. ECOORCHARD is therefore combining several approaches: (i) identifying and sharing innovative methods already implemented by fruit growers to increase FAB in EU countries ; (ii) assessing simple methods for farmers to monitor FAB ; (iii) quantifying the effect of FAB-boosting flower strips. The different on-farm sites, scientific trials and a web-based stakeholder platform to collect and share information are important elements to bring the collected experiences and scientific results very directly to the organic fruit growers. Interviews already started in 2015 with advisors and growers will provide useful information on original practices and methods used in orchard, to be shared during workshops with farmers for empowerment. ECOORCHARD aims to develop appropriate functional biodiversity practices for users’ needs and thus will identify and assess innovative techniques in terms of effectiveness and implementation conditions , carry out classical field experiments, on-farm and multi-site trials and collective workshops involving farmers, researchers and advisory services. More on : http://coreorganicplus.org/research-projects/ecoorchar

Habitat manipulation

Today, there is increasing interest among Swedish growers in biological diversity within the agricultural landscape. Many scientific studies have highlighted the services performed by beneficial organisms, which can help to improve the quantity and quality of crops. One tremendously important ecosystem service is biological control of pest insects and mites. The question is what growers can actually do to increase the abundance and diversity of natural enemies and whether this will have an impact on the pest population and, more importantly, on yield and quality of the crop. Another question is whether biodiversity is always positive for growers or whether there are negative aspects that should be dealt with. These relevant questions are addressed in the present report, the aim of which is to enlarge the current knowledge base on how to improve conditions for natural enemies, so-called habitat manipulation, within annual vegetable crops and perennial apple cropping systems. However, our aim was not to conduct a complete review of all available literature, but instead to select studies that may be of particular value for advisors and growers. We also chose to include the outcomes of a workshop on increasing diversity in apple orchards and interviews with advisors and vegetable growers to investigate the attitude and state of knowledge on habitat manipulation in Sweden today. We focus on natural enemies, arthropod pests and practices applied at field scale, and therefore exclude applications developed for greenhouse crops. Our hope is that advisors and interested growers in particular will find this report relevant and rewarding