Decision support systems to improve direct control methods of codling moth (BIOFRUITNET Practice Abstract)

A combined strategy of various direct (granuloviruses; nematodes) and indirect measures (population models, pheromone traps) can lead to a reduction in codling moth populations in the long term. Practical recommendation Codling moth population model: • Forecasting models such as the Fruitweb model can be used to predict treatment dates and reduce the need for spray treatments. • Codling moth forecasting models provide predictions of possible egg-laying and hatching dates and help fruit growers make more accurate codling moth treatment decisions. • The Fruitweb model shows the current course of a codling moth population (moth flight, egg laying, larval development) in the orchard; codling moth development depends on climate, location/site, temperature and day length. • The Fruitweb model is based on the codling moth model by Graf, Höhn, Höpli and Kuske (2018). • For targeted and optimized control, own infestation monitoring (attractant traps) and the recommendations from agricultural advisors should always be used additionally. Explanation of the codling moth Fruitweb model (Picture 1) • The forecast models are calculated with approximate population strengths; the respective local weather conditions are included in the calculation; the calculation is performed retrospectively with the measured weather data and prospectively with the weather forecasts. • The upper diagram shows the course of the borings (red dotted line), as well as the number of larvae in the respective larval stages (larval stages L1-L5: various shades of orange and yellow, see legend on the bottom). • The middle diagram shows the daily oviposition, i.e., the number of eggs per day (red line). • The lower diagram shows (in green) the number of fertile females per day, the flight of the females depends mainly on the weather conditions and the time of day (crepuscular)

Inokulumreduzierung des Schorfpilzes als Beitrag zur Kupferminimierung bzw. Kupferverzicht in der ökologischen Apfelproduktion

Im Zeitraum zwischen Oktober 2010 und Dezember 2016 wurden verschiedene Methoden zur Reduzierung des Inokulums des Apfelschorferregers getestet und hinsichtlich ihrer Wirkung auf Schorfinfektionen miteinander verglichen. Dazu wurden unterschiedliche Versuchsdurchführungen an mehreren Standorten in Deutschland (KOB Bavendorf, DLR Rheinpfalz und ÖON, Jork) durchgeführt. Der Schwerpunkt der Versuchsarbeit lag auf dem mechanischen Entfernen des Laubes mit unterschiedlichen Laubsaugern, kombiniert mit dem Einsatz von verschiedenen Pflanzenschutzvarianten. Zusätzlich zum mechanischen Entfernen des Laubes wurden Vinasse- und Hefepräparate eingesetzt, um die Zersetzung des Laubes zu beschleunigen und dadurch im Frühjahr Schorfinfektionen zu vermeiden. Die Laubsaugereinsätze fanden jeweils im Frühjahr, vor dem Beginn der Ascosporensaison, meistens im Zeitraum von Ende Februar bis Mitte März statt, der Termin sollte dabei immer möglichst kurz vor dem Beginn der Ascosporensaison liegen. Erfasst wurde zum einen die direkte Wirkung der Laubsammelgeräte auf die Laubmenge sowie zum anderen die indirekte Wirkung auf das Auftreten des Apfelschorfes mit Hilfe von Rosetten-, Lang-trieb- u. Fruchtschorfbonituren. Die direkte Wirkung auf die in den Obstanlagen verbleibenden Laubmengen beläuft sich auf 39 bis rund 94 % Reduzierung. Mit Hilfe von anschließender Handräumung konnte auch ein Wert von annähernd 100 % erreicht werden. Die Unterschiede in den Wirkungsgraden wurden dabei hauptsächlich durch unterschiedliche Beschaffenheiten der Obstanlagen verursacht, so führen beispielsweise Unebenheiten, wie tiefe Fahrspuren, zu spürbar verringerten Räumleistungen der Laubsauger. Die Wirkung auf das Auftreten des Apfelschorfs unterschied sich sowohl an den Standorten zwischen den Jahren, als auch zwischen den Standorten, bzw. Regionen teilweise erheblich. Die besten Wirkungsgrade wurden regelmäßig in der Bodenseeregion, am KOB Bavendorf erzielt. Betrachtet man isoliert das Auftreten von Schorf auf den Langtrieben und Früchten in den Standardpflanzenschutzvarianten, die an allen Versuchsstandorten vergleichbar durchgeführt wurden, so waren in den auswertbaren 16 Versuchsjahren (Versuchsjahr = Jahr pro Versuchsstandort) in 9 von 16 Versuchsjahren die Ergebnisse hinsichtlich des Schorfbefalls auf den Langtrieben in den Laubsaugervarianten besser als in den jeweiligen Vergleichsparzellen ohne Laubsauger. Noch etwas deutlicher fielen die Ergebnisse hinsichtlich des Befalls auf den Früchten aus, hier waren in 13 von 16 Versuchsjahren die Schorfbefallswerte in den Laubsaugervarianten geringer als ohne Laubsaugereinsatz, so dass die positiven Effekte im Laufe der Versuchstätigkeit deutlich überwogen. Auch der Einsatz von Hefepräparaten, besonders aber von Vinassen, hatte eine Wirkung auf das Auftreten der Schorfinfektionen

Use of Carpovirusine products against codling moth in organic fruit cultivation to prevent resistance (BIOFRUITNET Practice Abstract)

To avoid mass reproduction of codling moths in organic orchards (and to keep population levels sustainably below the economic damage threshold), regulation must be accomplished through a combined strategy of monitoring, pheromone confusion, nematodes, plant hygiene, and the use of granuloviruses. Practical recommendations Carpovirusine is a biological agent based on a specific insect pathogenic virus, the Cydia pomonella Granulovirus (CpGV). • Determine when the flight of C. pomonella begins by using Pheromone-Delta traps. A digital forecast model (e.g. Fruitweb) can also (additionally) help to screen flight begin. Flight activity means ongoing egg laying and hatching of the damaging larvae shortly afterwards (usually from the end of May onward). • Based on these screening results, start treatments with CpGV agents from hatching onwards with sufficient, regular application. If the infestation pressure is medium-high: Use at least 100ml CpGV per hectare to avoid resistance building (Antibiotics principle – an insufficient dosage risks resistance building). • Dosage/application rate can be adapted to infestation pressure, hatching prognosis, weather conditions and tree height, especially for the 2nd and 3rd generation (the number of possible generations varies in Europe related to climatic conditions. There are between 1 & 3 generations per year). Which CpGV-agent to use? • Madex Max /Carpovirusine Evo2: For farms in which no loss of efficacy was observed yet • Madex Top: If there is a loss of efficacy of MadexMax or in case of heavy infestation • ABC V14: In case of proven resistance against above Agents (emergency approval in Germany, only available after a positive resistance test done by the JKI-Institute and official approval) • Do not apply MadexTop in an extensive spraying sequence or with a constant low application rate (risk of resistance building) • In case of high fruit infestation (>1%), consider manually picking out infested fruits as well as application of nematodes in autumn (See Practice Abstract ‘Beneficial nematodes against codling moth in organic apple production’

Importance of robust varieties for sustainable organic pome fruit growing in the future (BIOFRUITNET Practice Abstract)

A reduced need for contentious inputs further enhances the sustainability of organic fruit growing and reduces labour and costs for the farm. This offers possibilities for new investments in other areas. Practical recommendation Shift your variety spectrum to more resistant varieties: • Professional fruit growing often means highly intensive systems. Growing sensitive varieties results in a high need for (sometimes contentious) inputs to ensure healthy orchards and stable, profitable yields. This means expensive, time-consuming and less sustainable economic systems. Support Consumer education and new marketing concepts: • The choice of varieties is highly connected to consumer and market demand and not easy to shift. Support better consumer education in terms of appreciation and acceptance of defects that do not affect the internal quality, such as optical shell defects (an apple must not look perfect!) • Work together with your bundlers and marketers to increase acceptance and to change the variety spectrum on the market to robust varieties in the medium and long term. Support regional/ national organic breeding activities & associations: Most of the currently available resistant varieties in pome fruits rely on single resistance genes, which slowly but steadily start to break down for various reasons: • Low genetic diversity of the varieties because of a high incest rate from a narrow breeding pedigree in the past • Higher selection pressure and adapting races of patogenic fungi due to few, broadly grown, large-scale varieties • Better climatic conditions for fungi and pests caused by climate change in many region

How to control Adoxophyes orana in organic apple production: decision making, mating disruption and direct control measures (BIOFRUITNET Practice Abstract)

Since the methods often do not produce satisfactory results individually, the regulation of A. orana is carried out by a combination of insect pathogens, especially Bt - preparations, insecticides, confusion, as well as parasitoids as natural enemies. Practical recommendations • The most important representative of the fruit leaf roller is A. orana (in Central Europe 2 generations/year) • Larvae of the overwintering generation cause feeding damage to the fruits, especially in September/ October, which concurrently might serve as an entry gate for secondary infections by different fruit pathogens (fungi). • In organic cultivation, different pheromones for prevention and Granulovirus & Bt agents for direct control are available to control the pest: • ISOMATE ® CLR MAX TT (pheromone): Combination dispenser to confuse the codling moth (C. pomonella) and fruit leaf roller (A. orana) • Bacillus thuringensis: Bt is a toxin-producing bacterium; in organic orchards, it is used to regulate free-feeding butterfly caterpillars • Granulovirus (e.g., Capex): infects the fatty tissue of the larvae so that they remain alive until the last larval stage and also still feed, therefore only limiting the damage by the subsequent generation; advantageous, however, is that due to the long life of the larvae, most parasitoids can fully develop in the larvae. The virus has a long-term effect because, after capex treatment, the granulovirus persists in the plants for a long time • Parasitoids: Parasitoids depend on nectar and pollen for their egg maturation; at sites with a high incidence of A. orana, the emergence of parasitoids can be promoted by including flowering plants

Insect boxes in organic orchards: Caution on ready-to-use solutions! (BIOFRUITNET Practice Abstract)

Nesting boxes also raise the population of some insect species, contributing to pest management, e.g., lacewing flies and hoverfly larvae feed predatorily. Practical recommendation INSTALLATION OF NESTING OFFERS: • Set up insect nesting offers/boxes in early spring, before the beginning of flight (wild bee boxes, lacewing fly boxes, etc.), protected from rain. • Align nesting boxes to the south or southeast (with lower solar radiation) • For protection from birds, a wire mesh can be attached at a sufficient distance. • Ensure easy access to nesting offers; they should not be covered by branches or leaves. • Implement or promote flower strips in the tree row or tramline, tall herbaceous borders along edge structures, design irrigation ponds naturally with low water zones, etc. These measures offer food and nesting sites for a wide variety of insects. INSECT NESTING AIDS - WHAT SHOULD BE CONSIDERED? Many insect nesting aids offered on the market are not suitable for practical use; they often can do more harm than good, therefore pay attention to the suitable material: • Avoid unclean, frayed holes in the wood: this causes a risk of injury • Pinecones, snail shells, straw and bark are of no use to wild bees and other insects of interest in the orchard. • Reed stalks should have a clean-cut edge: otherwise, there is a risk of destruction of wings • Hollow bricks not often get colonized, only in exceptional cases • Large boreholes > 10mm are usually not accepted • Pithy stems (blackberry stems): attach them individually and vertically to the scaffold for the highest colonisation rate • Avoid the use of cultivated bumblebees: there is a great risk of disease transmission to wild bumblebees --> Many cultivated bumblebees (imported from Turkey and other countries) compete with native species

Bamboo and deadwood: Get them out! Preventive measures to reduce codling moth in organic orchards (BIOFRUITNET Practice Abstract)

To avoid mass reproduction of the codling moth in organic orchards (and to keep population levels sustainably below the economic damage threshold), regulation must include a combined strategy of monitoring, confusion, nematodes, plant hygiene, and the use of granuloviruses. Practical recommendations • Control of the first generation of codling moth is crucial for containment. • Bamboo sticks, used in the scaffold system for stableness, are often very worn or cracked after a short period of time. As a result, they offer ideal overwintering quarters for the diapausing larvae of the codling moth. • In orchards with a high codling moth infestation, it can be assumed that existing bamboo poles in the orchard are strongly colonized by the codling moth and can promote codling moth populations. • In new orchards (especially in infested orchards), if possible, no more bamboo poles should be used. In old orchards, the support structure should be checked and replaced if necessary. • Another problem in old orchards is storing old wood next to commercial orchards; when plants are cleared, codling moth larvae remain in the support structure and in/on the trees. • Old wood piles, especially from infested plants, should not be stored near apple orchards over winter

Regulation of black rot (Diplodia seriata) in organic apple production (BIOFRUITNET Practice Abstract)

Removal of fruit mummies also has a preventive or infestation-reducing effect against the storage rot pathogens Neofabraea alba and N. perennans. Practical recommendation •Due to their tendency to form fruit mummies (Picture 4), some apple varieties are especially at risk of black rot infestation. These include Gerlinde, Elstar, Dalinbel, Natyra, Ingrid Marie and Wellant • Infections are favoured by high temperatures (20-26°C) and prolonged rain events • Heavy rainfall causes spores to be washed out of the fruit mummies, which then cause infection on the young fruit via the lenticels Prevention: • Choose robust varieties • Look for infection hint on fruits and leaves: o First infections may become visible from the beginning of June o Leaf spots ("frog eyes") may appear on the leaves near infested shoots or fruit mummies (Picture 1), and black necrotic infestations form on the fruit (Picture 2), which later grow to the size of a pinhead and develop a red edge o From August onwards, the outbreak of brown rot can occur from these primary infections as shown in (Picture 3). • Pick out fruit mummies consistently each year by hand before sprouting (February/March

Enhancing biodiversity with "Anchor plants" in organic orchards (BIOFRUITNET Practice Abstract)

Additional shrubs/woody plants in the orchard promote flowering and provide food (aphids, flowers, and fruits as winter food) for a variety of insects and birds. The more abundant flowering may also a positive impact on tourism and landscape attractiveness. Practical recommendation Selection of suitable anchor plant species and planting material: • Select shrubs with a long flowering period and with at least a low to medium nectar supply. • The flowering period of the selected species should be outside the fruit blossom period. • When selecting species o Avoid host plants of the cherry fruit fly and cherry vinegar fly, runner plants, wood plants suscepti-ble to fire blight, and vectors of the rain spot disease. o Select species that have fruits as winter food for birds. • Shrubs that can be recommended in Germany for use as anchor plants include wild privet (Ligustrum vul-gare); guelder rose (Viburnum opulus), European spindle (Euonymus europaeus); and wild roses (Rosa spp.). Implementation • Protect the plants against browsing by deer and hares. • Ensure sufficient watering of the new plantings, especially in the first year. • Plant during the optimal planting period: from late autumn to spring. • Place the anchor plants at the beginning and/or the end of each row or every second, if possible

Integration of high-perennial fringes along edge structures in organic orchards (BIOFRUITNET Practice Abstract)

Provision of increased supply of food and nesting sites, especially for insects. Flower strips also raise visual attractiveness and can provide a positive impact on regional or local tourism. Practical recommendation • Choose locations along edge structures within the orchards such as along fences, ditches or embankments or also unusable areas on the edges of the plantation. • Lay out the HPF with a width of 1.0m or wider for an optimal development. The minimum width for an HPF is 0.5m, otherwise it will be suppressed by grass. • The plant composition should include cut-tolerant herbs and food plants (e.g., caterpillar food plants, nectar/open flowers and pollen) and flower throughout the growing season (including selection of plant species with early flowering before apple blossom). Planting: • Timing: Depending on the region and weather conditions from early spring to autumn. When sowing in summer ensure proper irrigation. • Mill the surface two times at two week intervals to keep competitive pressure low. • Sow the seed only superficially (i.e., light germination) and roll it after sowing. • Mow the HPF once a year in late spring, so animals may overwinter there