Relative DNA Content and Chromosomal Relationships of some Meloidogyne, Heterodera, and Meloidodera spp. (Nematoda: Heteroderidae)
Lapp, N.A.; Triantaphyllou, A.C.
Journal of Nematology 4(4): 287-291
1972
ISSN/ISBN: 0022-300X PMID: 19319282 Document Number: 55537
The relative DNA content of hypodermal nuclei of preparasitic, 2nd-stage larvae was determined cytophotometrically in 19 populations belonging to 13 species of Meloidogyne, Heterodera and Meloidodera. In Meloidogyne hapla, M. arenaria, M. incognita and M. javanica, total DNA content per nucleus is proportional to their chromosome number, indicating that chromosomal forms with high chromosome numbers are truly polyploid. M. graminicola, M. graminis and M. ottersoni have a DNA content per chromosome significantly lower than that of the other Meloidogyne species. Within Heterodera, species with high chromosome numbers have proportionally higher DNA content, indicating again polyploidy. DNA content per chromosome in Meloidogyne is one-third that of Heterodera and one-half that of Meloidodera floridensis. The karyotypic relationships of the 3 genera are still not clearly understood. [AS].