Pests
Nematodes are microscopic roundworm endoparasites that feed on plant sap and cause significant yield losses. Varietal resistance is provided by genetic mechanisms that prevent pest reproduction and is assessed according to the International Seed Federation scale.
Mentioned in descriptions 13 637 varieties reference book.
Nematodes are microscopic roundworms ranging from 0.3 to 2 mm in size that act as obligate plant parasites. Most species penetrate root, stem, or bulb tissues, causing growth inhibition, wilting, and patchy crop development, with tissue damage often facilitating secondary infections.
Varietal resistance to nematodes is based on the plant's genetic apparatus, including specific R-genes that limit the feeding or reproduction of the pest. In some cases, protection is provided by a hypersensitive response, where local cell death occurs at the site of infection.
Protection efficacy is evaluated using International Seed Federation codes: HR denotes high resistance with limited parasite development under high inoculum pressure, while IR indicates intermediate resistance. The level of protection is race-specific and depends on the specific species and pathotype of the nematode.
Selection based on the description text, not official resistance ratings: such data is not available in registers. Mention indicates that the trait is discussed in the variety's sources; see the variety's profile for details on what is specifically stated.
Prunus amygdalus x Prunus persica
The Regents of the University of California
Solanum lycopersicum L. · Tomato
Campbells Seeds
Solanum tuberosum L. · Potato
Station de Recherche du Comité Nord G.I.E.
Nicotiana tabacum L. · Tobacco
ProfiGen Do Brasil
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Hybrids between Citrus x aurantium L. x Citrus trifoliata L.
VARIOS OBTENTORES
Nicotiana tabacum L. · Tobacco
NOVARTIS SEEDS
Solanum lycopersicum L. · Tomato
CLAUSE
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Gossypium hirsutum L. · Upland cotton
CALIFORNIA PLANTING COTTON SEED DISTRIBUTORS
Vitis L. · Grapevine
INCONNU (FR)
Ipomoea batatas (L.) Lam. · Sweet potato
Labonte Don R. / Villordon Arthur Q. V / Smith Tara Parker / Clark Christopher A.
Solanum lycopersicum L. · Tomato
SEMINIS VEGETABLE SEED IB
Vitis vinifera L. · Common grape vine
LLOYD/HAROLD/AUSTIN
Vitis vinifera L. · Common grape vine
LLOYD/HAROLD/AUSTIN
Solanum lycopersicum L. · Tomato
UNITED GENETICS SEEDS CO