ROOT-KNOT NEMATODE RESISTANCE IN CUCUMBER AND HORNED CUCUMBER

Cucumber (Cucumis sativus L.) and horned cucumber (C. metuliferus Naud.) germplasm were evaluated for their resistance to root-knot nematodes (Meloidogyne spp.). All 24 C. metuliferus cultigens evaluated were resistant to ail root-knot nematodes tested-M. incognita (Kofoid and White) Chitwood race 3, M. arenaria (Neal) Chitwood race 2, and M. hapla Chitwood. All 884 C. sativus cultigens (cultivars, breeding lines, and plant introduction accessions) tested were resistant to M. hapla and few to M. incognita race 3. Only 50 of 884 C. sativus cultigens evaluated were somewhat resistant to M. arenaria race 2 and M. incognita race 3. A retest of the most resistant C. sativus cultigens revealed that LJ90430 [an accession of C. sativus var. hardwickii (R.) Alef.] and 'Mincu' were the only cultigens that were moderately resistant to M. arenaria race 2. LJ90430 was the only cultigen, besides the two retested C. metuliferus cultigens, that was resistant to M.javanica (Treub) Chitwood. All C. sativus cultigens retested, including LJ90430, were highly susceptible to M. incognita races 1 and 3. The two C. metuliferus cultigens retested were highly resistant to all root-knot nematodes tested-M. arenaria race 2, M. incognita races 1 and 3, and M. javanica.