This study examined the polymerase chain reaction (PCR) amplified internal transcribed spacer (ITS) and 26S ribosomal DNA (rDNA) regions of 15 entomopathogenic nematode isolates including Steinernema feltiae syn. bibionis, S. glaseri, seven strains of S. carpocapsae, four strains of Heterorhabditis bacteriophora, and two field isolates. RDNA length variation was not observed among the isolates ...

Pasteuria penetrans spore adhesion to Meloidogyne javanica second-stage juveniles (J2) was examined following several different pretreatments of the latter. The detergents sodium dodecyl sulfate and Triton X-100, the carbohydrates fucose and alpha-methyl-D-mannoside, and the lectins concanavalin A and wheat germ agglutinin reduced spore attachment. Spores exposed to M. javanica surface coat (SC...

Two new "dumpy" mutants (Hbdpy-2 and Hbdpy-3) of Heterorhabditis bacteriophora were induced and characterized. Mutants (hermaphrodites and males) that hatched from eggs were shorter and wider than the wild-type strain. This phenotype was not discernible in young animals until 24 hours after hatching from eggs or in mutants that developed from infective juveniles. Scanning electron microscopy re...

Two lines of Aegilops squarrosa (G 3489 and G 1279) and Triticum cultivars Anza, Cocorit, Produra, Chinese Spring, Nugaines, and a synthetic hexaploid were screened for resistance to Meloidogyne chitwoodi. Reproduction of M. chitwoodi, expressed as eggs per gram root, was low (P < 0.01) on G 3489 and the synthetic hexaploid. Reproduction on all other cultivars tested was high although differenc...

Meloidogyne chitwoodi and M. hapla were pathogenic to both roots and tubers of Russet Burbank potato. Both species affected root growth at 15, 20, and 25 C, but not 30 C. Meloidogyne chitwoodi reprotluced best at 15, 20, and 25 C and M. hapla at 25 and 30 C. Reproduction of M. chitwoodi was reduced at 30 C; reproduction of M. hapla was reduced at 15 C and less at 20 C. The reproductive potentia...

The northern root-knot nematode (Meloidogyne hapla) is a major pathogen of processing carrot in New York, significantly reducing marketable yield and profitability. Severely infected carrots are stubby, galled and forked and therefore unmarketable. In field microplot trials in 1996 and 1998, the incidence and severity of root-galling increased and the marketable yield of carrot decreased as the...

Meloidogyne chitwoodi developed and reproduced more rapidly than M. hapla in potato roots at 15, 20, or 25 C when both species of nematodes were inoculated simultaneously at 250 or 1,000 juveniles of each. At 30 C significantly more M. hapla than M. chitwoodi females were found at the lower inoculum level after 41 days. More M. chitwoodi than M. hapla juveniles were extracted from soil at 15, 2...