Interactions between entomopathogenic nematodes and imidacloprid for rose sawfly control

Abstract

Rose sawfly, Arge ochropus (Gmelin), is one of the most important pests of ornamental plants such as roses and wild rose bushes in Northern Iran. We investigated the interactions between the insecticides imidacloprid and the entomopathogenic nematodes Heterorhabditis bacteriophora and Steinernema carpocapsae as control agents of fifth-instar larvae in the laboratory. The larvae were very susceptible to S. carpocapsae (LC 50 : 21 infective juvenile per larva) and H. bacteriophora (LC 50 : 32). Combinations of two imidacloprid rates (LC 30 and LC 50 ) and four rates of each nematode species (LC 25 -LC 75 ) were tested. Combinations with the lower imidacloprid rate except for that with the highest H. bacteriophora rate caused higher mortality than both respective single-agent treatments. In combination with the higher imidacloprid rate, only one combination with H. bacteriophora and two combinations with S. carpocapsae caused higher mortality than both respective single-agent treatments. Interactions were generally stronger at the lower imidacloprid rate and were stronger for S. carpocapsae (synergistic in seven combinations, additive in one) than for H. bacteriophora (synergistic in two, additive in six). Synergistic imidacloprid-S. carpocapsae combinations could be a useful tool for the control of A. ochropus larvae that would simultaneously control other common pests susceptible to imidacloprid.

First report of the entomopathogenic nematode, Steinernema carpocapsae, from Moghan region of Iran and its efficacy against the turnip moth, Agrotis segetum Denis and Schiffermuller (Lepidoptera: Noctuidae), larvae

“…Various genera and species of the EPNs have been isolated from Iran and investigated in different aspects such as morphology and phylogeny (Kary et al, 2009and Nikdel et al, 2010, natural incidence in insect hosts (Karimi et al, 2009), efficacy against agricultural pests (Ebrahimi et al, 2011(Ebrahimi et al, , 2014(Ebrahimi et al, , 2016, interaction of entomopathogenic nematodes and chemical pesticides (Sheykhnejad et al, 2014), and their interaction with insect immune system (Ebrahimi et al, 2018).…”

Natural Warriors against Stored-Grain Pests: The Joint Action of Beauveria bassiana and Steinernema carpocapsae

“…EPNs have been evaluated in combination with insecticides, biocontrol agents, and parasitoids to increase their efficacy against insect pests [ 49 , 99 , 100 , 101 , 102 , 103 ]. Several factors can influence the interaction between EPF and EPNs, such as the species and strains of EPF and EPNs, the target insect host, application parameters, and environmental conditions [ 49 , 103 , 104 , 105 , 106 , 107 ].…”

Nematode Pathogenesis of Insects and Other Pests

“…Recently, the susceptibility of larvae of the rose sawfly, Arge ochropus (Gmelin) (Hymenoptera: Argidae), an important pest of roses and wild rose bushes in northern Iran, to infection by H. bacteriophora and S. carpocapsae was reported in laboratory bioassays (Sheykhnejad, Ghadamyari, Koppenhöfer, & Karimi, 2014). The results indicated that H. bacteriophora (LC 50 : 32 IJs/larva) had low infectivity to A. ochropus than S. carpocapsae (LC 50 : 21 IJs/larva); however, their efficacy were not at a level that would make foliar applications of EPNs alone feasible.…”