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

DEL VALLE, E.E.; FRIZZO, L.S.; MALMIERCA, M.; ZBRUN, M. V.; LAX, P.; DOUCET, M. E.

JOURNAL OF PEST SCIENCE

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2015

1612-4758

Chemical insecticides often are not efficient inreducing Alphitobius diaperinus populations in poultry farmsand have induced insect resistance. Entomopathogenic nematodes(EPNs) appear as an alternative to pest biocontrolagents; however, their efficiency on rice hull litter is still unknown.The aim of this study was to evaluate the potential ofSteinernema rarum (CUL isolate), Heterorhabditis bacteriophora(SMCisolate) and their symbiotic bacteria as biocontrolagents of A. diaperinus larvae and adults in rice hull litter.Mortality of insect adults and fifth- and seventh-instar larvaewas determined in Petri dishes containing filter paper or ricehull. The effect of Xenorhabdus szentirmaii and Photorhabdusluminescens on L7 and adults in rice hull substrate wasalso evaluated. Moreover, the effectiveness of the EPNs wasassessed in bags in an environment simulating the prevailingconditions in a broiler chicken farm. Under laboratory conditions,insect mortality was significantly affected by EPNspecies, substrate, insect stage and time after application.Mortality of L5 and L7 caused by EPNs in rice hulls reached apeak of 64 and 57.3 %, respectively, whereas symbiotic bacteria applied on rice hull showed low mortality rate at bothinsect 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 adultmortality being low for both species. We conclude that infectivejuveniles from S. rarum CUL and H. bacteriophoraSMC isolates can be used as biological control agents of A.diaperinus larvae in chicken litter containing rice hulls.