Biological control of Alphitobius diaperinus with Steinernema rarum CUL and Heterorhabditis bacteriophora SMC and feasibility of application in rice hull

Abstract

Chemical insecticides often are not efficient in reducing Alphitobius diaperinus populations in poultry farms and have induced insect resistance. Entomopathogenic nematodes (EPNs) appear as an alternative to pest biocontrol agents; however, their efficiency on rice hull litter is still unknown. The aim of this study was to evaluate the potential of Steinernema rarum (CUL isolate), Heterorhabditis bacteriophora (SMC isolate) and their symbiotic bacteria as biocontrol agents of A. diaperinus larvae and adults in rice hull litter. Mortality of insect adults and fifth-and seventh-instar larvae was determined in Petri dishes containing filter paper or rice hull. The effect of Xenorhabdus szentirmaii and Photorhabdus luminescens on L7 and adults in rice hull substrate was also evaluated. Moreover, the effectiveness of the EPNs was assessed in bags in an environment simulating the prevailing conditions in a broiler chicken farm. Under laboratory conditions, insect mortality was significantly affected by EPN species, substrate, insect stage and time after application. Mortality of L5 and L7 caused by EPNs in rice hulls reached a peak of 64 and 57.3 %, respectively, whereas symbiotic bacteria applied on rice hull showed low mortality rate at both insect stages. In the simulated poultry farm conditions, S. rarum and H. bacteriophora caused up to 40.8 and 50.4 % mortality of A. diaperinus larvae, respectively, but with adult mortality being low for both species. We conclude that infective juveniles from S. rarum CUL and H. bacteriophora SMC isolates can be used as biological control agents of A. diaperinus larvae in chicken litter containing rice hulls.

New findings of Heterorhabditis bacteriophora and Steinernema rarum (Nematoda: Heterorhabditidae, Steinernematidae) in Córdoba, Argentina

“…This species has a lim ited known distribution in the word, since it has been detected only in USA and Brazil (Shapiro Ilan et al, 2003;BarbosaNegrisoli et al, 2010). The previous findings of S. rarum (Doucet et al, 2008;Del Valle et al, 2016), and the data pro vided in this paper indicate that this species is the more abundant of the genus Steinernema in Argentina.…”

“…In Argentina, S. rarum has been detected in the provinces of Córdoba (Doucet et al, 2008), and Santa Fe (Del Valle et al, 2016). The two populations found in this study extend its dis tribution in our country.…”

The lesser mealworm Alphitobius diaperinus: a noxious pest or a promising nutrient source?

“…), and entomopathogenic nematodes (Del Valle et al . ). In lab assays, high larval infection rates were achieved after application of a B. bassiana strain, originally isolated from adult house flies ( Musca domestica L. Diptera: Muscidae), as aqueous conidial suspension or dust; in contrast, adult mortality was low (Steinkraus et al .…”

“…Recently, two isolates of the entomopathogenic nematodes Steinernema rarum (Doucet) (Nematoda: Steinernematidae) and Heterorhabditis bacteriophora Poinar (Nematoda: Heterorhabditidae) showed promising control efficacy against A. diaperinus larvae in chicken litter containing rice hulls (Del Valle et al . ). In poultry insect pest management studies using ‘macro‐biocontrol’ agents, the efforts to exploit the predaceous hister beetle, Carcinops pumilio (Erichson) (Coleoptera: Histeridae), a naturally occurring predator, for the management of M. domestica in caged‐layer poultry houses, were hurdled by the presence of A. diaperinus larvae, which significantly reduced the survival of C. pumilio eggs and larvae (Watson et al .…”

Draft Genome Sequence of Photorhabdus luminescens Strain DSPV002N Isolated from Santa Fe, Argentina

“…intended to overcome the activity and proliferation of other opportunistic microorganisms ( 2 ). In this work, we report the draft genome sequence of P. luminescens strain DSPV002N, which was isolated from hemolymph of dead Galleria mellonella larvae from Santa Fe, Argentina ( 3 ). Purified genomic DNA was obtained using the Wizard genomic DNA purification kit (Promega), according to the instructions for DNA isolation from Gram-negative bacteria.…”