Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2007
Publication Date: 12/1/2007
Citation: Dong, W., Brenneman, T.B., Holbrook Jr, C.C., Timper, P., Culbreath, A.K. 2007. The Interaction between Root-knot Nematode (Meloidogyne arenaria) and Cylindrocladium Black Rot (CBR) in Runner Peanut [abstract]. In: Proceedings of the American Peanut Research and Education Society, Birmingham, AL, July 9-12, 2007 p. 47. Interpretive Summary: not required
Technical Abstract: Cylindrocladium black rot (CBR), caused by Cylindrocladium parasiticum, and root-knot nematode, caused by Meloidogyne arenaria, are important soilborne diseases on peanut. Greenhouse and microplot experiments were conducted with the runner peanut genotypes C724-19-15 (resistant to M. arenaria), Georgia-02C (resistant to CBR), and C724-19-25 (susceptible to M. arenaria and CBR) to better understand the interactions between the two pathogens. In the greenhouse, root rot ratings were increased in all three peanut genotypes by addition of 500-3000 eggs/plant of M. arenaria with low inoculum level (1.0 microsclerotia/g soil) of C. parasiticum. The nematode did not affect the root rot induced by a high inoculum level (5.0 microsclerotia/g soil) of C. parasiticum. Severe pod galling was present on Georgia-02C and C724-19-25, but not C724-19-15. Gall ratings were not affected by C. parasiticum inoculations in the greenhouse or microplots. In microplot experiments, the root rot ratings from nematode-susceptible genotypes Georgia-02C and C724-19-25 were higher in plots infested with M. arenaria (200-1000 eggs/500 cm3 soil) and C. parasiticum than in plots with C. parasiticum alone; however, M. arenaria did not increase the root rot ratings on the nematode-resistant genotype C724-19-15. This was inconsistent with the greenhouse results. Simultaneous inoculation with M. arenaria decreased yield incrementally on C724-19-25 and Georgia-02C as C. parasiticum inoculum levels increased, but even a high level of M. arenaria (1000 eggs/500cm3 soil) did not decrease yield of C724-19-15 when also inoculated with C. parasiticum.