Browsing by Author "Kaakko, Emma"

The biological control of carrot psyllid (Trioza apicalis Förster (Hemiptera: Triozidae)) was the focus of this study. The carrot psyllid is an important pest that causes significant yield loss. There is a lack of knowledge of the biological control of carrot psyllid with predators. In a recent study, larvae of Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) and adult Anthocoris nemoralis Fabricius (Heteroptera: Anthocoridae) were used as biological agents. The field research was carried out in Western Finland in the year 2021. The flight peak was monitored with yellow sticky traps, and predators were applied at the beginning of the flight peak. The number of carrot psyllids’ nymphs and eggs was calculated in the biocontrol treatments as well as untreated controls and chemical control treatments and results were compared. Due to severe drought during the field experiment, biocontrol treatments were studied also in semi-field conditions in the pallet collar cultivation experiment. The number of predators per square meter in the semi-field experiment was the same as in the field experiment and the effect on the controlled amount of carrot psyllids was observed. Both results were analysed with SPSS-program. According to the results, the combined treatment with C. carnea and A. nemoralis (Anthocoridae), where C. carnea were released one week later than A. nemoralis, decreased statistically significantly the number of carrot psyllids’ eggs. The C. carnea treatment or A. nemoralis (Anthocoridae) treatment alone did not reduce the number of eggs or larvae. There is no previous research on the biological control of carrot psyllid, so there is no background literature on the subject. The research aimed to get information on the biological control of carrot psyllid and that goal was achieved. It is essential to do further research on this subject. The following aims might be to find out more information on predator density, the timing of the predator release, and the effects of different predators’ combinations in the biological control of carrot psyllids.