1a. Objectives (from AD-416):
Objective 1: Develop molecular methodologies for the identification and classification of alfalfa nematodes, needed to support diagnosticians and growers in making timely and accurate management decisions in response to nematode outbreaks, and to aid plant breeders in developing new nematode resistant cultivars. Objective 2: Identify and characterize nematodes found with endophytes of alfalfa, forage grasses, and weeds in order to discover novel associations with increased crop productivity or improved adaptability to arid sites.
1b. Approach (from AD-416):
1. Nematodes that infect alfalfa and other forage legumes, grasses, rotation crops, or potential weed hosts will be identified using molecular markers including ribosomal, mitochondrial, Hsp90, and other nuclear genes. 2. New diagnostic assays, including RFLPs, and conventional or real-time PCR assays will be developed for Meloidogyne spp., Pratylenchus spp., Ditylenchus spp., or others affecting these plants. 3. Molecular information from the diagnostic work will be integrated with morphological data and information regarding biogeography, pathogenicity, and host range to generate new and improved phylogenetic schemes. 4. Molecular diagnostic tools to aid in screening resistant alfalfa germplasm will be developed to detect and quantify nematodes from infected alfalfa tissue. 5. Fungal-feeding nematodes and their associated fungal endophytes will be isolated from alfalfa, forage grasses, or weeds and identified and characterized by morphological and molecular methods. 6. Fungal-feeding nematodes will be cultured with fungal symbionts in lab cultures to determine suitability of endophytes to support nematode growth and reproduction.
3. Progress Report:
This is a bridge project for 8042-22000-284-00D, "Enhanced Alfalfa and Forage Productivity Through Molecular Detection and Characterization of Plant Nematodes." Please see the final annual report under 8042-22000-284-00D. Additional progress made on this bridge project in support of Objective 1 included molecular identification and characterization of cereal cyst nematode from wheat, possible alfalfa cyst nematode from alfalfa in the midwest, an aggressive species of root-knot nematode from South Carolina, dagger nematodes from Oregon, and a probable new species of root-knot nematode from garlic mustard weed from Oregon.