1 research outputs found
Screening Spanish isolates of steinernematid nematodes for use as biological
6 pagesEntomopathogenic nematodes (EPNs) are one of the best non-chemical alternatives for insect pest control,
with native EPN strains that are adapted to local conditions considered to be ideal candidates for
regional biological control programs. Virulence screening of 17 native Mediterranean EPN strains was
performed to select the most promising strain for regional insect pest control. Steinernema feltiae (Filipjev)
(Rhabditida: Steinernematidae) Rioja strain produced 7%, 91% and 33% larval mortality for the
insects Agriotes sordidus (Illiger) (Coleoptera: Elateridae), Spodoptera littoralis (Boisduval) (Lepidoptera:
Noctuidae) and Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), respectively, and was selected as
the most promising strain. The S. feltiae Rioja strain–S. littoralis combination was considered the most
suitable to develop the Rioja strain as a biocontrol agent for soil applications. The effect of soil texture
on the virulence of the Rioja strain against S. littoralis was determined through dose–response experiments.
The estimated LC90 to kill larvae in two days was 220, 753 and 4178 IJs/cm2 for soils with a clay
content of 5%, 14% and 24%, respectively, which indicates that heavy soils produced negative effects on
the virulence of the Rioja strain. The nematode dose corresponding to the LC90 for soils with a 5% and
14% clay content reduced insect damage to Capsicum annuum Linnaeus (Solanales: Solanaceae) plants
under greenhouse microcosm conditions. The results of this research suggest that an accurate characterization
of new EPN strains to select the most suitable combination of insect, nematode and soil texture
might provide valuable data to obtain successful biological control under different ecological scenarios in
future field applicationsPeer reviewe