Title: Further observations on chrornosomal processes during oogenesis of Meloidogyne haplu (Nematoda)
Abstract: SUMMARY Oogenesis of two populations (A and B) of Meloidogyne hapla was studied using the Giemsa C banding technique. Population A underwent a normal meiotic process and had 2 n =’ 30 somatic chromosomes while population B showed a single maturation division of equational type and 2 n somatic karyotype = 45. In both cases, the Giemsa C technique provided good figures, even of the “pseudointerphase” or “diffuse stage” wliich takes place during oocyte growth and which previously has been designed by this term because the poor staining of chromosomes when Schiff or orcei,n techniques were used. In population A, this phase corresponded to diplotene. In population A 30 chromosomes could be distinguished during oogonial mitosis, but only nine or ten pairs were observed during diplotene. At dialtinesis lifteen bivalents were present. Maturation was normal : the first polar body with fifteen chromosomes was rejected and a second mitotic division followed. The nine or ten pairs observed during meiotic prophase were thought to be relictual chromosome feature and the higher number observed in the other stages could be the result of some chromosome breaks. The variation of the chromosome number previously signalized for M. hapla (n = 14-15-16-17) would be related to this phenomenon. Population B possessed 45 chromosomes. At the early prophase of the single maturation division, chromosomes were not paired, contrary to population A. At th’e end of the prophase some of them assembled forming large chiasmatic or aggregate chromosomes ; chromatin reduction did not take place at the end of the division.
Publication Year: 1981
Publication Date: 1981-01-01
Language: en
Type: article
Access and Citation
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot