Parasitism genes expressed in the esophageal gland cells of root-knot nematodes encode proteins that are secreted into host root cells to transform the recipient cells into enlarged multinucleate feeding cells called giant-cells. Expression of a root-knot nematode parasitism gene which encodes a novel 13-amino-acid secretory peptide in plant tissues stimulated root growth. Two SCARECROW-like tr...

Abstract Root-knot nematodes ( Meloidogyne spp.) cause serious damages on most crops. Here, we report a high-quality genome sequence of exigua (population Mex1, Costa Rica), major pathogen coffee. Its mitogenome (20,974 bp) was first assembled and annotated. The nuclear then constructed consisting 206 contigs, with an N50 length 1.89 Mb total assembly 42.1 Mb.

Soils and roots of field crops in low-rainfall regions of the Pacific Northwest were surveyed for populations of plantparasitic and non-plant-parasitic nematodes. Lesion nematodes (Pratylenchus species) were recovered from 123 of 130 non-irrigated and 18 of 18 irrigated fields. Pratylenchus neglectus was more prevalent than P. thornei, but mixed populations were common. Population densities in ...

Growth and yield of cotton were best with combinations of fumigants and organophosphate and carbamate nematicides. Organophosphates or carbamates used alone did not give season-long control of root-knot nematodes. Long-term control was poor because the temporary sublethal effects of these materials diminished soon enough lhat the nematodes could reproduce. The nematodes survived the treatments ...

Recent advances in molecular biology have enabled the genotyping of individual nematodes, facilitating the analysis of genetic variability within and among plant-pathogenic nematode isolates. This review first describes representative examples of how RFLP, RAPD, AFLP, and DNA sequence analysis have been employed to describe populations of several phytonematodes, including the pinewood, burrowin...

Roundworms of the Nematoda comprise one of the largest animal phyla on Earth (1). They inhabit diverse terrestrial and aquatic niches through adaptations of a spectrum of trophic groups, including parasites that threaten human, animal and crop plant health. The most well-known nematode, Caenorhabditis elegans, is a native soil-dwelling microbivore that has emerged as a premier model for animal ...

Restrictions on the use of conventional nematicides have increased the need for new methods of managing plant-parasitic nematodes. Consequently, nematode-antagonistic microbes, and active compounds produced by such organisms, are being explored as potential additions to management practices. Programs in this area at the USDA Agricultural Research Service investigate applied biocontrol agents, n...

Brassica plants once incorporated into soil as green manures have recently been shown to have biofumigant properties and have the potential of controlling plant-parasitic nematodes. In Washington State, plant-parasitic nematodes are successfully managed with synthetic nematicides. However, some of the synthetic nematicides became unavailable recently or their supply is limited leaving growers w...

In the Pacific Northwest, alfalfa (Medicago sativa) is host to two species of root-knot nematodes, including race 2 of the Columbia root-knot nematode (Meloidogyne chitwoodi) and the northern root-knot nematode (Meloidogyne hapla). In addition to the damage caused to alfalfa itself by M. hapla, alfalfa's host status to both species leaves large numbers of nematodes available to damage rotation ...

Organic soil amendments have been employed as an alternative to or in combination with, chemical nematicides and cultural practices to control plant-parasitic nematodes. Rye (Secale cereale L.) has been shown to be effective in minimizing the damage caused by root-knot nematodes (Meloidogyne incognita (Kofoid and White) Chitwood) when grown as a cover crop and then incorporated into the soil pr...