African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6576

Full Length Research Paper

Host-status of thirty-two maize genotypes to Meloidogyne incognita race 2 and Meloidogyne javanica in South Africa

G. L. Ngobeni, P. W. Mashela* and M. S. Mphosi
School of Agricultural and Environmental Sciences, University of Limpopo, Private Bag X1106, Sovenga 0727, Republic of South Africa.
Email: [email protected]

  •  Accepted: 01 March 2012
  •  Published: 26 March 2012

Abstract

Meloidogyne incognita race 2 and Meloidogyne javanica are widely distributed in South Africa where they cause enormous crop yield losses. Host-status of commercial maize (Zea mays L.) genotypes to the two nematode species was investigated under greenhouse conditions. Thirty-two maize genotypes, for each nematode species were arranged in a randomised complete block design, with six replicates. The experiments were conducted in summer and repeated in autumn. Fifty-six days after inoculating each treatment with 10 000 juveniles, reproductive factors and penetration indices (PIs) were subjected to analysis of variance and means separation achieved using Duncan’s multiple-range test. Reproductive factors suggested that three open-pollinated varieties, namely: OBATAMPA, QPM-SR and QS-OBA were non-host to both M. incognita race 2 and M. javanica in all trials. Certain hybrids and OPVs were also non-hosts to the two nematode species, although the result was not consistent throughout all the trials. Penetration indices suggested that OBATAMPA had post-infectional non-host status, whereas QPM-SR and QS-OBA had pre-infectional non-host status. In conclusion, results of this study demonstrated that non-host status to M. incognita race 2 and M. javanica existed in certain maize genotypes that are commercially available in South Africa. Also, in some of the genotypes, the non-host status was introgressible.

 

Key words: Penetration index, pre-infectional resistance, post-infectional resistance, reproductive factors.