BIOLOGICAL EVALUATION AND COMPARISON OF FOUR FLORIDA ISOLATES OF <I>MELOIDOGYNE FLORIDENSIS</I>

Authors

  • J. D. Stanley
  • J. A. Brito
  • N. Kokalis-Burelle
  • J. H. Frank
  • D. W. Dickson

Keywords:

host suitability, intraspecific variability, enzymatic profile, Meloidogyne floridensis, morphometrics, root-knot nematode

Abstract

Stanley, J. D., J. A. Brito, N. Kokalis-Burelle, J. H. Frank, and D. W. Dickson. 2009. Biological evaluation and comparison of four Florida isolates of Meloidogyne floridensis. Nematropica 39:255-271. A study was conducted to characterize the morphology, enzymatic profile, and host preference of four isolates of the peach root-knot nematode, Meloidogyne floridensis. No morphological or biochemical differences were observed among the four isolates. Each isolate showed some mean variability in morphometrics values, but overlapped in their range values (P > 0.05). In total, 1,027 females extracted from peach, pepper, tobacco, and tomato did not differ in their isozyme phenotype for esterase and malate dehydrogenase, and matched those reported in the original description. In host differential tests all four isolates of M. floridensis exhibited the same reaction as that of M. incognita race 2, with pepper, tobacco, tomato and watermelon being susceptible, and cotton and peanut, resistant. In comparative host status studies, both root-knot nematode resistant and susceptible peach cultivars were susceptible to all four isolates. Both resistant and susceptible cultivars of corn, pepper, soybean, and tomato were evaluated. All four isolates of M. floridensis reproduced poorly, but were able to overcome the resistance of the Mi-1 gene in tomato cv. Crista. Two isolates reproduced poorly, but were not affected by the N gene resistance in the pepper cv. Charleston Belle, whereas two isolates reproduced well on this cultivar. Both the root-knot nematode resistant corn cv. Mp 710 and susceptible cv. Dixie 18 were susceptible to all four isolates; whereas, both the resistant soybean cv. Forrest and susceptible cv. S64-J1 were immune to all four isolates of M. floridensis.

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Published

2009-12-01

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Articles