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.
Solanum lycopersicum L. · Tomato
RAMIRO ARNEDO, S.A.
Solanum tuberosum L. · Potato
Hodowla Ziemniaka Zamarte sp. z o.o. - Grupa IHAR
Beta vulgaris Sugar Beet Group · Sugar beet
KWS| KWS SAAT AG
Solanum lycopersicum L. · Tomato
UNITED GENETICS SEEDS CO
Beta vulgaris Sugar Beet Group · Sugar beet
DLF Beet Seed APS
Solanum tuberosum L. · Potato
Sloots Aardappelkweekbedrijf B.V.
Solanum lycopersicum L. · Tomato
Y³ksel Tohum Tarim San. ve Tic A.S.
Solanum lycopersicum L. · Tomato
Kees Konst
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V. 2025243007
Prunus persica (L.) Batsch · Peach
Solanum lycopersicum L. · Tomato
ENZA ZADEN B.V.
Cucurbita maxima Duchesne x Cucurbita moschata Duchesne
KANEKO SEEDS CO LTD
Medicago sativa L. · Alfalfa
WELSH PLANT BREEDING STATION
Beta vulgaris Sugar Beet Group · Sugar beet
KWS Saat SE Finanzbuchhaltung
Trifolium repens L. · White clover
P.BREED.INST.WALES
Solanum lycopersicum L. · Tomato
Syngenta Seeds B.V.
Solanum lycopersicum L. · Tomato
DE RUITER SEEDS
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Capsicum annuum L. · Bell pepper
RAMIRO ARNEDO, S.A.
Solanum lycopersicum L. · Tomato
DE RUITER SEEDS
Hordeum vulgare L. · Barley
W WEIBULL
Beta vulgaris Sugar Beet Group · Sugar beet
KWS Saat AG, DE
Avena strigosa Schreb. · Black oat
Lammers Seed Options B.V.
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.