Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 7, 2000
Publication Date: N/A
Interpretive Summary: Several species and races within species of root-knot nematodes are serious pests of cultivated hot pepper. The development of cultivars with genetic resistance to root-knot nematodes is the most efficient and environmentally benign way of controlling this production problem. Host resistance also provides the most viable and easily implemented alternative to the use of methyl bromide soil fumigation to control root- knot nematodes. The studies reported in this paper were conducted to determine if resistance previously described by the authors to the southern root-knot nematode, Meloidogyne incognita, was effective against other species and races of root-knot. The studies showed that in addition to M. incognita, the resistance was effective against M. arenaria races 1 and 2 and M. javanica, but was not effective against M. hapla. The resistance has substantial value to the development of resistant cultivars through its effectiveness against three species of root-knot nematodes. However, evaluations of other plant germplasm resources are needed to find a separate source of resistance to the fourth species.
Technical Abstract: Four Capsicum chinense cultigens with known reactions to M. incognita were characterized for resistance to Meloidogyne arenaria races 1 and 2, M. hapla, and M. javanica in greenhouse and growth chamber tests. The M. incognita-resistant cultigens PA-353, PA-398, and PA-426 exhibited high resistance to M. arenaria race 1; the M. incognita-susceptible PA-350 was susceptible to M. arenaria race 1. Meloidogyne arenaria race 2 and M. javanica were not highly pathogenic to any of the C. chinense cultigens. However, PA-353, PA-398, and PA-426 supported an average of 98.1% and 94.8% fewer (P<0.05) M. arenaria race 2 and M. javanica eggs per gram fresh root, respectively, than PA-350. Meloidogyne hapla was pathogenic to all four C. chinense cultigens. PA-353, PA-398, and PA-426 will be useful sources of resistance to M. arenaria races 1 and 2, M. javanica, and M. incognita for developing resistant habanero cultivars; however, an alternative source of resistance must be identified for M. hapla.