In 2008 and 2009 we studied molluscicidal activity of 26 substances in 89 different treatments under laboratory conditions. The experiments in which slugs (Arion spp.) were a part took place in two ...series: 1) with the injection of active substances in slug intestines; and 2) with the application of pellets. After giving the injection we observed 100% mortality of slugs in treatments with Bacillus thuringiensis var. kurstaki (0.25 ml in 10% concentration/individual), caffeine (0.25 ml in 10% concentration/individual), sodium dodecyl sulphate (0.25 ml in 10% concentration/individual, 0.125 ml in 10% concentration/individual, 0.125 ml in 5% concentration/individual, 0.0625 ml in 10% concentration/individual), and pirimicarb (0.25 ml in 10% concentration/individual, 0.125 ml in 10% concentration/individual, 0.125 ml in 5% concentration/individual, 0.0625 ml in 10% concentration/individual). Meanwhile, the application of pellets resulted in the highest (100%) slug mortality when sodium dodecyl sulphate in 0.5% concentration with caraway as a supplement was used.
Z V letih 2008 in 2009 smo v laboratorijskih razmerah preizkušali limacidno delovanje 26 snovi v 89 različnih obravnavanjih. Poskusi, v katere smo vključili polže lazarje (Arion spp.), so potekali v dveh serijah, in sicer z injiciranjem aktivne snovi v prebavilo polžev in z uporabo pelet. Pri injiciranju smo 100 % smrtnost polžev ugotovili v obravnavanju z bakterijo Bacillus thuringiensis var. kurstaki (0,25 ml v 10 % koncentraciji/osebek), kofeinom (0,25 ml v 10 % koncentraciji/osebek), natrijevim dodecil sulfatom (0,25 ml v 10 % koncentraciji/osebek; 0,125 ml v 10 % koncentraciji/osebek; 0,125 ml v 5 % koncentraciji/osebek; 0,0625 ml v 10 % koncentraciji/osebek), in pirimikarbom (0,25 ml v 10 % koncentraciji/osebek; 0,125 ml v 10 % koncentraciji/osebek; 0,125 ml v 5 % koncentraciji/osebek; 0,0625 ml v 10 % koncentraciji/osebek), medtem ko smo največjo (100 %) smrtnost polžev pri uporabi pelet dosegli z natrijevim dodecil sulfatom v 0,5 % koncentraciji z dodatkom kumine.
SUMMARY
Slug problems in arable crops and vegetables have increased drastically during the past few decades. Observations on slug damage to oilseed rape suggested that fresh, anaerobically digested ...organic material from a biogas production plant is molluscicidal. To find out whether digested matter can be used for the control of agricultural pest slugs, a series of exeriments were carried out. The laboratory experiments demonstrated strong mollusc repellent and molluscicidal effects of digested organic matter against the three most important pest slugs of Switzerland, Arion lusitanicus, A. distinctus and Deroceras reticulatum. The effects were restricted to fresh digested matter and were rapidly lost when the material was stored, and also after application in the field. In the field experiment, fresh digested matter greatly reduced slug damage to lettuce in comparison with the untreated plots. At present, the chemical nature of the molluscicidal compound(s) in digested matter is unknown, but environmental pollutants such as heavy metals can be ruled out. Current research aims at a new formulation which is easier to apply and has a longer‐lasting molluscicidal or slug‐repellent effect, and at optimising the dosage and number of applications.