Steinmehl zur Regulierung des Rapsglanzkäfers Meligethes spp.

Summary in the original language of the document

In organic agriculture, treatments with rock dusts for soil amendment, disease prevention, or insect control have a long tradition. Clinoptilolite (a naturally occurring zeolite) was tested against pollen beetle Meligethes spp. in oilseed rape fields in order to find a control strategy compatible with the guidelines for organic agriculture in Switzerland. Dust and spray applications were evaluated in several large-scale field trials from 2008 to 2010. Dust applications using 300-750 kg / ha pulverized Clinoptilolite (particle size <0.1 mm; product Klinofeed, company Unipoint, Switzerland) were applied using a drop-box fertilizer spreader or a Vicon pendulum spreader. For spray applications the same Clinoptilolite (product Klinospray) with a particle size of 0.017 mm was applied at rates of 30 - 50 kg / ha with a wetting agent (Heliosol, 2 l / ha; 600 l waster / ha) using a standard field crop sprayer. Under the dry and sunny weather conditions in 2009 and 2010, the treatments significantly reduced the number of pollen beetles by 50 to 80% until seven days after treatment (BBCH 51-54). Under the rainy weather conditions in 2008, no reduction of pollen beetles was observed. In all experimental years a visibly more intense flowering was observed in the treated plots. Pod setting on the main raceme was significantly increased in the treated plots.