Year 2 of Biological control of Rumex obtusifolius is in progress. A great deal of this year’s activities has been done.

Rootstocks infected with Pyropteron chrysidiforme larvae were brought from CABI Switzerland to AIS Slovenia. When adult insects emerged, female and male insects were mated. Afterwards, eggs of the insects were collected and prepared for field inoculation. 2nd year’s Inoculation was done on two locations (Ajdovščina and Murski Črnci) in the end of June/beginning of July. The inoculated plants were already marked with a GPS coordinate, as first inoculation was done one year before. At each location around 125 toothpicks with 30 eggs attached to them were stuck onto plants, assigned to treatments with two- and three years of inoculation with P. chrysidiformae. Additional 25 plants were also marked for annual establishment rate evaluation.  Initial observations on field suggest we have already had some success with the method of biological control. When searching for the marked R. obtusifolius plants, we found quite a few of them already dead (73 dead plants in Ajdovščina and 18 dead plants in Murski Črnci).

Digging of inoculated plants, selected for estimation of annual establishment of the insect, will be done later this year, in autumn. 

Andrej Vončina

Toothpicks with Pyropteron chrysidiforme eggs

Tracking of marked plants and field inoculation

Inoculation of Rumex obtusifolius