Influence of Alfalfa Plant Growth on the Multiplication Rates and Ceiling Population Density of Meloidogyne hapla

Authors

  • J. W. Noling
  • H. Ferris

Abstract

The rates of reproduction and multiplication of Meloidogyne hapla decreased as a result of self-regulatory, density-dependent processes with time and nematode population increase in the soil and roots of Medicago sativa cv. Cuf 101. Juvenile, egg, and mature female population densities increased at a maximum rate until damage to the host resulted in alfalfa yield reductions. Temporal differences in multiplication and reproduction rates of M. hapla were observed to be a function of initial population density (Pi), host damage, and root biomass, indicating increased levels of competition for a constant but limited number of feeding sites. Over time, a log linear relationship emerged between multiplication rate of M. hapla and Pi. Slopes of -0.90953 for combined eggs and juveniles and -0.71349 for mature females indicated a gradual approach to ceiling densities. Reproductive rates decreased exponentially from an initial maximal value of 200 to a relatively constant rate of 53 eggs per female. Key words: density dependence, intraspecific competition, reproduction, population dynamics, root-knot nematode, Medicago sativa.

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Published

1986-10-15

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Articles