Efficiency of Entomopathogenic Nematodes Steinernema carpocapsae Against Sunn Pest, Eurygaster testudneria Under Laboratory Conditions

Jabbar, A.Sh., A.S. Mohamed and A.M. Hussein. 2024. Efficiency of Entomopathogenic Nematodes Steinernema carpocapsae Against Sunn Pest, Eurygaster testudneria Under Laboratory Conditions. Arab Journal of Plant Protection, 42(1): 108-112. https://doi.org/10.22268/AJPP-001205 Eurygaster testudneria (Hemiptera: Scutelleridae), is one of the most economic pests that attack and cause serious damage to wheat and barley grains. Filter paper bioassay was conducted under laboratory conditions using different concentrations of Steinernema carpocapsae species which is one of the most effective entomopathogenic nematodes (EPNs) applied to control a wide range of insect pests all over the world. Two stages of E. testudneria were used in all experiments with three concentrations of EPN. The target pest stages were nymphs and adults and the EPN concentrations used were 50, 100 and 150 IJs/insect with only tap water as the control treatment. The mortality rates were recorded 24, 48, 72, 96 and 120 hours after treatment. Consequently, LC50, LC90 (lethal concentration) and LT50 (lethal time) were estimated for each stage. The results obtained showed that the LC50 values for both stages (adults and nymphs) of E. testudneria were 122.9 and 11.3 IJs/insect and the LC90 were 477.6 and 83.9 IJs/insect, respectively. The mortality increased by increasing the exposure time for all concentrations. The LT50 and LT90 for both adults and nymphs were 4.42 and 2.6 days by using 50 IJs/insect, whereas the values of LT50 for both stages were 4.01, 1.9 and 4.02, 1.8 by applying 100 and 150 IJs/insect respectively. The mortality rate of nymphs was 90-100%, whereas that of adults was 65-80%, 7 days after exposure. There was a significant difference among treatments. The current study represents the first report of using EPNs as a biological control agent against E. testudneria in Iraq. Keywords: Biological control, EPNs, Steinernema carpocapsae, sunn pest, Eurygaster testudneria.