Cytogenetic studies in Sinipta dalmani Stål (Orthoptera: acrididae). II. Effects of centric fusions on chiasma frequency and distribution

  title={Cytogenetic studies in Sinipta dalmani St{\aa}l (Orthoptera: acrididae). II. Effects of centric fusions on chiasma frequency and distribution},
  author={MI Remis},
  journal={Genetics, Selection, Evolution : GSE},
  pages={263 - 272}
  • MI Remis
  • Published 1989
  • Biology
  • Genetics, Selection, Evolution : GSE
Summary - Spontaneous and polymorphic centric fusions were detected in a population of Sinipta dalmnni (2n: 23, XO male/XX female) from Entre Rios Province (Argentina). The spontaneous rearrangement affects 2 autosomes (M and Mwhile the polymorphic one involves the sex chromosome and the fifth member of the complement. The former has irregular behaviour presenting a high frequency of non disjunctional orientation during metaphase I. This mutation does not affect either the frequency or the… Expand
Effects of chromosome rearrangements on sperm formation in Sinipta dalmani (Orthoptera: Acrididae)
The DNA content of giant spermatids was mainly 2c, suggesting that there may be any meiotic misbehaviour during meiosis, and other mechanism, such as cell fusion, may be involved in the production of abnormal sperm. Expand
Three samples of Sinipta dalmani polymorphic for the M4 pericentric inversion were assayed for chromosomal variation and allozymic variation at 18 loci (9 enzymatic systems). No sig-nificantExpand
A polymorphic centric fusion enhances chiasma interference in Leptysma argentina (Orthoptera): a chiasma distribution study
A chiasma distribution study in diplotene in the grasshopper Leptysma argentina and a discussion concerning the possible origin of the fusion 3/6 polymorphism is held. Expand
Cytogenetic studies inSinipta dalmani Stal (Orthoptera: Acrididae). III: Pericentric M4 inversion affecting morphological traits
Three population samples of Sinipta dalmani polymorphic for the M4 inversion were analysed for five body-size-related traits: total body, tegmina, third femur, third tibia and thorax lengths, suggesting that the differences between karyomorphs are largely additive. Expand
Spontaneous Centric Fusions Affecting Chiasma Conditions in Dichroplus elongatus (Orthoptera)
Results revealed that a) some fusions per se may affect chiasma conditions, b) the intensity of such effect varies among chromosome pairs. Expand
Chromosome polymorphisms in natural populations of the South American grasshopper Sinipta dalmani
The results showed that the chromosome polymorphisms in S. dalmani may be associated with a significant decrease in genetic recombination, which may explain in part their maintenance in some areas of its geographical distribution. Expand
On the origin of B-chromosomes: neo XY systems and X-like supernumeraries in Orthoptera
It is pointed out that small Bs could originate from polysomy of the smallest chromosomes, tolerated because of the few genes involved in Cylindrotettix obscurus, and the minute-B category is attributed to residua... Expand
Micro-Evolution in Grasshoppers Mediated by Polymorphic Robertsonian Translocations
  • P. Colombo
  • Medicine, Biology
  • Journal of insect science
  • 2013
It is concluded that Robertsonian polymorphic grasshopper species share some properties with inversion polymorphic species of Drosophila, such as the central-marginal pattern (marginal populations are monomorphic, central populations are highly polymorphic). Expand
Population differentiation in the grasshopper Sinipta dalmani: body size varies in relation to karyotype and climatic conditions
The results in S. dalmani demonstrate significant variation in body size within polymorphic populations and among geographical populations, which may be explained under a selective scenario. Expand
Phenotypic pattern over centric fusion clinal variation in the water-hyacinth grasshopper, Cornops aquaticum (Orthoptera: Acrididae)
There is a strong inverse correlation of fusion frequency with temperature, which indicates that these polymorphisms may be related to increased tolerance of colder climates in this originally tropical species, or some other correlated variable. Expand


Cytogenetic Studies in Sinipta Dalmani Stål (Orthoptera: Acrididae). I. Effects of a Pericentric Inversion on Chiasma Conditions
Two populations of Sinipta dalmani from Entre Rios Province (Argentina) are polymorphic for a pericentric inversion in pair M4, where the inversion precludes the crossing over within its limits in the heterozygous condition and increases terminal chiasma frequency in homozygosis. Expand
A Spontaneous Centric Fusion Heterozygote in the Tropical Grasshopper, Valanga Nigrocornis (Burmeister)
A fusion between two telocentric autosomes, M8 and M9, is described which reduces significantly the chiasma frequencies of both the large and the medium members of the chromosome complement. Expand
Cytogenetic studies in Sinipta dalmani (Orthoptera: Acrididae)
  • Cytogenetic studies in Sinipta dalmani (Orthoptera: Acrididae)
  • 1989
Chromosomes In Evolution Of Eukaryotic Groups
The role of chromosome change
  • 1983
Cytogenetic studies in Sinipta dalmani (Orthoptera: Acrididae). I
  • 1989
Estudios citogeneticos en Orthoptera de Sudam6rica
  • Tesis Doctoral Fac de Ciencias Exactas y Naturales
  • 1984
Population cytology of the genus Oedaleonotus . I . The karyotypic facies of Oedaleonotus enigma ( Scudder )
  • Chromosoma ( Berl )
  • 1988
Population cytology of the genus Oedaleonotus. I. The karyotypic facies
  • 1988
Possible causes of variation
  • 1986