Print version ISSN 0102-0536
SILVA, Giovani O da; PINHEIRO, Jadir B; VIEIRA, Jairo V and CARVALHO, Agnaldo DF de. Selection for carrot genotypes resistance to root-knot nematodes in field and greenhouse. Hortic. Bras. [online]. 2011, vol.29, n.3, pp.335-341. ISSN 0102-0536. http://dx.doi.org/10.1590/S0102-05362011000300013.
We verified the relation among the evaluated characters in field and greenhouse, concerning to the evaluation to root-knot nematode (Meloidogyne spp.) for the carrot crop, to identify for which ones it is possible to differentiate among genotypes and to verify the possibility of evaluation only in one environment or the elimination of characters with high correlation. Thirty eight and thirty one families from the carrot populations '0812518' and '0812519', and the cultivars Brasília and Kuronan as tolerant and susceptible standards, respectively, were evaluated. In a field whose soil was naturally infected by a mix of Meloidogyne incognita race 1 and Meloidogyne javanica, the selection to resistance to root-knot nematode was based on lower percentage of infection in the root, of the major genotypes of carrot production in t/ha and reproduction factor; and in greenhouse, to each one of the same nematode species and too for a mix of both, was evaluated the index of gall and index of egg mass. There is no possibility of selection in only one condition or the elimination of some characters, indicating that, to obtain more yielding and more tolerant cultivars, the combined selection in the various characters and environments are necessary. In the field experiment, it was only possible to differentiate the genotypes for root yield. In the greenhouse, it was possible to identify superior genotypes for all characters tested. However, the average population was not better than the 'Brasilia' standard that originated these populations. This result confirms the necessity to search for more efficient methods of selection.
Keywords : Daucus carota; Meloidogyne incognita; Meloidoigyne javanica; reproduction factor.