A filter paper bioassay was developed for testing the efficacy of nematodes and other agents for control of Diaprepes abbreviatus larvae. Surfactants, with and without Steinernema riobravis, were screened first in the filter paper bioassay and then in a potted citrus seedling study. The results of the two assays were in agreement on the relative merits of the compounds tested. Surfactants incre...

Daily irrigated, 80% pan replacement, and nonirrigated field plots of Kentucky bluegrass (Poa pratensis L.) were inoculated with a mixture of Steinernema carpocapsae (All strain) and Heterorhabditis bacteriophora (HP-88 strain) in 1988. In 1989, daily irrigated and nonirrigated plots were inoculated with HP-88 alone. The turf and associated soil contained populations of Tylenchorhynchus dubius,...

The entomogenous nematode Steinernema feltiae was encapsulated in an alginate matrix containing a tomato seed. When these capsules were placed on 0.8% agar for 7 days, the seed germinated and ca. 20% of the nematodes escaped from the capsules, whereas only 0.1% escaped from capsules without seeds. When capsules containing nematodes and a seed were planted into sterilized or nonsterilized soil, ...

Entomopathogenic nematodes (EPNs) from the Heterorhabditidae and Steinernematidae families are well-known biocontrol agents against numerous insect pests. The infective juveniles (IJs) are naturally occurring in the soil and their success in locating and penetrating the host will be affected by extrinsic/intrinsic factors that modulate their foraging behavior. Characterizing key traits in the i...

We determined the effects of crop residue on the persistence of an entomopathogenic nematode, Steinernema carpocapsae. During 2 consecutive years, nematodes were applied at rates of 2.5 x 10 and 1.0 x 10 infective juveniles/m(2) to small field plots planted with corn. Nematode persistence was monitored by exposing Galleria mellonella larvae to soil samples from plots with and without crop resid...

The effect of Steinernema riobrave and Heterorhabditis bacteriophora on population density of Mesocriconema xenoplax in peach was studied in the greenhouse. Twenty-one days after adding 112 M. xenoplax adults and juveniles/1,500 cm(3) soil to the soil surface of each pot, 50 infective juveniles/cm(2) soil surface of either S. riobrave or H. bacteriophora were applied. Another entomopathogenic n...

Hypothesis: Under exploitative competition, unrelated parasites should reproduce at a faster rate than related parasites. Organisms: The parasitic nematode Steinernema carpocapsae and the insect host Galleria mellonella. Methods: We created ten replicate lines each of high-migration (unrelated) and low-migration (related) nematode populations, and allowed them to evolve for 20 host passages. Re...