Effect of mechanical soil treatment in blueberry orchards

From June 2004 onwards a trial was conducted on a blueberry farm in the Lüneburg Heath, Northern Germany, in which methods of mechanical soil cultivation were compared with mulching. The aim was to determine how far the mechanical methods and equipment established for soil management in viniculture and pomiculture can be adapted to blueberry cultivation, and can be improved. The results showed a clear advantage of the methods based on mulch technology in the shape of increased yields. Whilst the mechanical treatments provided acceptable weed control, they cannot be recommended for routine use at present because of strong yield reductions associated with damage to the shallow root system of highbush blueberry shrubs

Diplodia seriata, cause of black fruit rot in organically grown apples in Holland, Belgium and Northern Germany

A fruit rot resembling Gloeosporium infections but appearing on fruits prior to harvest was noticed in organic apple orchards in Holland, Belgium and Northern Germany in 2007. Infections were most commonly observed on ‘Elstar’, but other cultivars were also affected. Fruit colonisation progressed in two steps, whereby a latent stage of sunken black lesions in immature fruits gave rise to a rapidly spreading firm brown rot upon fruit ripening. Isolation experiments from both stages consistently yielded a single species of fungus identified as Diplodia seriata, formerly known under the teleomorph name Botryosphaeria obtusa. Lesions of D. seriata were also seen on leaves as necrotic light brown spots surrounded by a purple halo, and occasionally on small twigs as cankers. Fruit mummies on apple twigs were heavily colonised by D. seriata and are thus likely to carry inoculum for fruit infections during late summer or in the following growing season

Hot Water Dipping in Northern Germany- on farm results after four years of scientific work

In general, organic grown apples (Malus x domestica Borkh.) are not treated with chemical fungicides to pre-vent storage decay and these fruits may suffer up to 30% decay during storage. Preliminary experiments had shown that hot water dipping of apples may be an alternative. To inhibit Gloeosporium rot (Pezicula alba, P. malicortis) water temperature may be of about 50°C and dipping time from 60 sec up to 240 sec. The objec-tive was to determinate the suitable hot water treatment that prevent decay incidence and maintain fruit qual-ity (firmness, scale symptoms). In between the years 2002 and 2005 the test were repeated and a recom-mendation for the apple varieties in the area Northern Germany was elaborated

Varmt brusebad mod lagerråd

Overbrusning af æbler med varmt vand ser ud til at have god virkning på de mest almindelige lagerrådsvampe på æbler

Regulierung der Pfennigminiermotte (Leucoptera scitella) in Norddeutschland

In normal years, Leucoptera scitella is an insignificant pest in organic apple orchards of Northern Germany. In some years, however, its population rises so that it is neces-sary to control this pest. We made a trial in an organic orchard aimed at testing the potential of Neem Azal and BT to control L. scitella. Neem Azal sprayed during the period of egg hatching was effective at controlling L. scitella. A first strategy for on-farm use has been developed

Versuche zur Regulierung des Apfelwicklers Cydia pomonella in Norddeutschland

The population control of the codling moth (Cydia pomonella) is of great importance in ecological fruit-growing. Given suitable climatic conditions, an increase in population density can lead to explosive growth of subsequent generations. In the work described here we attempted (1) to determine the efficacy of plant protection preparations certi-fied for ecological fruit-growing, and (2) to develop a suitable application strategy. We found that a Granulovirus (Madex3) and Neem Azal were able to provide effective control of C. pomonella. The reduced effect of Madex 3 as reported e.g. from South-ern German orchards (KIENZLE et al. 2006) could not be observed in our trials

Netzschwefel als Multitalent zur Behandlung von Krankheiten und Schaderregern im ökologischen Kernobstanbau

In the last eight years research work has been done at the Fruit Research and Extension Centre Jork (OVB Jork) on strategies to control apple scab (Venturia inaequalis), powdery mildew of apple (Podosphaera leucotricha), sooty blotch(several fungis) and apple rust mite (Aculus schlechtendali) on organic grown pome fruit. Since 1997 different control strategies with reduced copper use and copper substitutes and sulphur with different application rates were tested in several trials on trees in organic apple orchards near Hamburg, Germany. The strategies were tested on the cultivar `Elstar´. The results show that sulphur has significant effects to control fruit scab, leave scab, powdery mildew, sooty blotch and rust mite

Results in research on lime sulphur and other products to control apple scab under northern German climate conditions

In 2003 six apple scab control strategies were tested, three with only lime sulphur in different application strategies, another three strategies with different amounts of copper. The strategies were tested in an organic apple orchard near Hamburg, Germany, on a 15 year old `Elstar´ plantation. Due to the recorded infection periods and the infection load the different strategies were tested. The results show that a proper lime sulphur strategy is quite successful to fight apple scab (< 4% infected fruit), has good side effects on apple mildew (< 2%) and only little russetting (< 5%) compared to strategies with copper fungicides. ablto fight fruit scab as well as leave scab. A proper strategy means no application later than 15 hours after infection, enough spraying water (drip off), usage of a 1,5-2% lime sulphur-solution and only very little direct sunlight

Erste Versuchsergebnisse mit Backpulver gegen Apfelschorf

Five different strategies to control apple scab have been tested during the summer season in 2005. Four of the strategies are based on sulphur, one is based on Bicarbonate. The test took place in an apple orchard, which was slightly infected by apple scab. Bicarbonate was able to control scab on the fruits in the orchard even as during storage at 84% (Abbott). The best sulphur variant could control apple scab in storage up to 95% (Abbott)

Untersuchungen der Abundanz von Schadorganismen und der Entwicklung des Inokulums des Schorfpilzes in einer Mischkultur aus vier genetisch wenig verwandten Apfelsorten

Im dreijährigen Projekt zu „Untersuchung der Abundanz von Schadorganismen und der Entwicklung des Inokulums des Schorfpilzes in einer Mischkultur aus vier genetisch wenig verwandten Apfelsorten“ sollte erforscht werden, inwieweit Mischkulturen die Ausbreitung wichtiger Kernobstschädlinge sowie die Entwicklung des Schorfpilzes beeinflussen. Die Ergebnisse wurden anhand eines Vergleichs einer Mischkulturpflanzung von vier genetisch wenig verwandten Apfelsorten mit einer Reinkulturpflanzung der gleichen Sorten erarbeitet. Als Apfelsorten wurden ´Holsteiner Cox´, ´Elstar´, ´Fuji´ und die schorfresistente Sorte ´Topaz´ aufgepflanzt. Während der Versuchsjahre wurden Schaderregerbonituren auf Apfelsägewespe (Hoplocampa testudinea), Apfelrostmilbe (Aculus schlechtendali), Obstbaumspinnmilbe (Panonychus ulmi) und Apfelschorf (Venturia inaequalis) in der Mischkultur und in der Reinkultur durchgeführt. Anhand der Boniturergebnisse konnte die Entwicklung des Schaderregerbefalls in beiden Kulturen beobachtet und bewertet werden. Eventuell auftretende betriebswirtschaftliche Nachteile der Mischkultur wurden anhand der Parameter Arbeitsleistung bei der Ernte, Aufwand an Kulturmaßnahmen, Ertrag und Befahrbarkeit der Anlage bei starker Belastung erfasst und beurteilt. Aufgrund des geringen Alters der Versuchsanlage konnte noch keine Auswirkung einer Mischkulturpflanzung auf den Schaderregerbefall beobachtet werden. Die Schaderreger traten partiell über die ganze Anlage verteilt auf, es konnte mit Ausnahme der Schorfanfälligkeit der Sorte ´Fuji´ keine sortenspezifischen Anfälligkeiten gegenüber Schaderregern beobachtet werden. Diese Aussagen werden erst in nachfolgenden Jahren möglich sein. Ebenso fielen aufgrund des geringen Baumalters keine zusätzlichen Pflanzenschutz- und Pflegemaßnahmen in der Mischkultur an. Auch hierzu werden erst in nachfolgenden Jahren Aussagen getroffen werden können