Abstract
Oogenesis was investigated using a fluorescent staining technique with Hoechst 33258 in several isolates of facultative meiotic parthenogenetic -Meloidogyne hapla race A, M. chitwoodi, M. fallax - and obligate ameiotic (mitotic) parthenogenetic - M. hapla race B, M. javanica - and isolate Xa of an unidentified species. Without fertilisation, the somatic chromosome number was restored by fusion of pronucleus and second polar body in M. hapla race A, M. chitwoodi, and M. Sallax isolates. In oocytes of isolate Xa, a second meiotic division occurred in a few cases while in all other cases the somatic chromosome number was restored by duplication of the chromosomes of the egg nucleus after the first division. In one mono-female line of Xa, embryonic development occurred within the body of the female and was genetically controlled. In M. hapla race B and M. javanica, maturation of the oocytes consisted of one mitotic division. This study confirmed that a large variation of the mode of reproduction exists in Meloidogyne spp., which may be a reason for their world-wide success. In one M. hapla race A isolate, only 12 % of the oocytes of inseminated females contained sperm, and prophase I instead of prometaphase I oocytes were found posterior to the spermatheca. (C) Orstom/Elsevier, Paris
Original language | English |
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Pages (from-to) | 393-399 |
Journal | Fundamental and applied nematology |
Volume | 21 |
Issue number | 4 |
Publication status | Published - 1998 |
Keywords
- M. fallax
- M. hapla
- M. javanica
- Meiosis
- Meloidogyne arenaria
- Parthenogenesis
- Root-knot nematode