Polyploid complexes of Glycine tabacina (Labill.) Benth. and G. tomentella Hayata revealed by cytogenetic analysis

Genome ◽  
1987 ◽  
Vol 29 (3) ◽  
pp. 490-497 ◽  
Author(s):  
R. J. Singh ◽  
K. P. Kollipara ◽  
T. Hymowitz
Keyword(s):  
Papua New Guinea ◽  
Chromosome Pairing ◽  
Cytogenetic Analysis ◽  
Adventitious Roots ◽  
Meiotic Chromosome ◽  
New Guinea ◽  
Chromosome Behavior ◽  
Intraspecific Hybridization ◽  
The Common ◽  
Glycine Tabacina

Observations on geographical distribution, cytotypes, crossability, and meiotic chromosome behavior in intra- and interspecific F1 hybrids revealed that the complexes of Glycine tabacina (2n = 40, 80) and G. tomentella (2n = 38, 40, 78, 80) evolved through allopolyploidization. It is apparent from this study that 80-chromosome tabacinas are composed of two distinct morphological complexes having one common genome: with and without adventitious roots. In contrast, the tomentellas are inseparable morphologically. They are composed of accessions with at least three genomic complexes: (i) 2n = 80, accessions from Australia and Taiwan; (ii) 2n = 80, an accession from Papua New Guinea; and (iii) 2n = 78, accessions from Australia and Papua New Guinea. Hybrids within each group showed complete synapsis and set normal seeds; however, hybrids between the groups apparently differed by one genome and were completely sterile. Chromosome pairing in triploid interspecific F1 hybrids (2n = 59, 60) indicated that G. canescens (2n = 40) was probably the donor of the common genome for 80-chromosome tabacinas and tomentellas. Glycine latifolia (2n = 40) appears to have contributed its genome to G. tabacina (2n = 80) but could not have participated in the speciation of 80-chromosome tomentellas. Likewise, the 38-chromosome G. tomentella has no genomic affinity with 80-chromosome tabacinas but has complete affinity with 80-chromosome tomentellas. On the basis of present findings and the results published earlier, the evolution of the genus Glycine will be discussed. Key words: Glycine spp., genome, hybridization (intraspecific), hybridization (interspecific), speciation.

Intergeneric hybrids of Hordeum vulgare with Agropyron caninum and A. dasystachyum

1985 ◽  
Vol 27 (4) ◽  
pp. 387-392 ◽  
Author(s):  
George Fedak
Keyword(s):  
Hordeum Vulgare ◽  
Chromosome Pairing ◽  
Meiotic Chromosome ◽  
Intergeneric Hybrids ◽  
Spindle Fibre ◽  
Chromosome Behavior ◽  
Paternal Parent ◽  
Agropyron Caninum

Hybrids were obtained by pollinating Hordeum vulgare cv. Betzes with Agropyron caninum (4x) and A. dasystachyum (4x) at frequencies of 1.4 and 6.1% of pollinated florets, respectively. The hybrids were sterile and phenotypically resembled the paternal parent, except for floret structure which was intermediate between the parental types. Chromosome pairing at meiosis was very low and thus provided no indication of homoeology between parental genomes. Abnormal meiotic chromosome behavior in meiocytes that occurred in sectors on the 'Betzes' × A. dasystachyum hybrid was attributed to abnormal spindle fibre function.Key words: intergeneric hybrids, Hordeum vulgare, Agropyron caninum, Agropyron dasystachyum.

Homology of chromosomes of the X genomes in common and Uruguayan dallisgrass, Paspalum dilatatum

Genome ◽  
1991 ◽  
Vol 34 (6) ◽  
pp. 950-953 ◽  
Author(s):  
Byron L. Burson
Keyword(s):  
Chromosome Pairing ◽  
Chromosome Numbers ◽  
The Other ◽  
Paspalum Dilatatum ◽  
Intraspecific Hybridization ◽  
The Common ◽  
Complete Sets ◽  
The Relationship ◽  
Metaphase I

Two biotypes of dallisgrass, Paspalum dilatatum Poir., designated common and Uruguayan, have chromosome numbers and genome formulas of 2n = 5x = 50 (IIJJX) and 2n = 6x = 60 (IIJJXX), respectively. The relationship between the X genomes in these two biotypes is unknown, and each was arbitrarily assigned the letter X to designate an unknown genome. This study was undertaken to determine the relationship between the X genomes in these two biotypes. Because both biotypes are apomicts and cannot be crossed, a sexual intraspecific F1 hybrid (2n = 45) between sexual yellow-anthered (2n = 4x = 40; IIJJ) and common dallisgrass biotypes was crossed with Uruguayan dallisgrass. This F1 hybrid has complete sets of the I and J genomes but only 5 of the 10 chromosomes of the X genome from common dallisgrass. Two hybrids were recovered. One had 52 and the other had 53 chromosomes, which associated at metaphase I as 22 bivalents + 8 univalents and 23 bivalents + 7 univalents, respectively. Twenty bivalents represent pairing of members of the I and J genomes, and those in excess of 20 represent pairing between members of the two X genomes. The remaining members of the X genome from the Uruguayan biotype were present as univalents at metaphase I. This demonstrates that those chromosomes of the X genome from the common biotype that were present are homologous to members of the X genome of the Uruguayan biotype. Both hybrids are aposporous facultative apomicts with some sterility.Key words: meiosis, intraspecific hybridization, chromosome pairing, genome relations, apomixis.

THE ANALYSIS OF MEIOSIS IN HYBRIDS. I. ANEUPLOID HYBRIDS

1981 ◽  
Vol 23 (2) ◽  
pp. 209-219 ◽  
Author(s):  
G. Kimber ◽  
L. C. Alonso ◽  
P. J. Sallee
Keyword(s):  
Triticum Aestivum ◽  
Mathematical Models ◽  
Chromosome Pairing ◽  
Meiotic Chromosome ◽  
Triticum Aestivum L ◽  
Equal Frequency ◽  
Chromosome Behavior ◽  
Telocentric Chromosomes ◽  
Genomic Relationships ◽  
Meiotic Analyses

The use of telocentric chromosomes in the analysis of the genomic relationships of wheat Triticum aestivum L. em Thell. and its relatives is described and 20 examples are given. The connection between this method of analysis and other mathematical theories of chromosome pairing in hybrids is established. A demonstration of the validity of the assumption that all chromosome arms pair at an equal frequency in calculating expected meiotic analyses is presented. This establishes a practical basis for the development of further mathematical models for predicting meiotic chromosome behavior. Numerical values of the genomic relationships of wheat and its immediate relatives are given.

scholarly journals Beyond a Common Code: Cameroon Pidgin English - the Language of the Elite and the Masses

2021 ◽  
Vol 2 (2) ◽  
pp. 22-29
Author(s):  
Rachel Ayuk Ojong Diba
Keyword(s):  
Papua New Guinea ◽  
Qualitative Data ◽  
New Guinea ◽  
Linguistically Diverse ◽  
Small Population ◽  
Common People ◽  
Common Code ◽  
The Common ◽  
The Masses

The principal purpose of this paper is to underline the usefulness and efficacy of Cameroonian Pidgin English (CPE) in dealing with the intense multilingualism of Cameroonians in a rural enclave in Cameroon and in the Diaspora. CPE is a highly stigmatized but extensively used language of wider communication in Cameroon. Cameroon is second only to Papua New Guinea in terms of its multiplicity of languages for a relatively small population and the shunned CPE is the language that trudges through this multi-ethnicity, multiculturalism and multilingualism to not only provide a feeling of togetherness to Anglophone Cameroonians but to also allow them communicate efficiently and cordially. CPE was incipiently a language for the uneducated, this contribution shows that today CPE is not only the language of the common people; it is also the language of the Cameroonian elite. Using qualitative data – recordings of natural conversations from individuals in Lower Fungom and written conversation from online fora comprising Cameroonians of all walks of life, this contribution demonstrates that CPE is an emblematic language which Cameroonians use when communication would otherwise be impossible and still use it even when there is an option (though one-legged) of other languages. The paper demonstrates how multilingualism functions even in rural circles. It is also demonstrates the benefits of Pidgins and Creoles in linguistically diverse settings, which are relatively uncommon.

Observations of probable camouflaging behaviour in a semi-commensal common spotted cuscus Spilocuscus maculatus maculatus (Marsupialia: Phalangeridae) in New Ireland, Papua New Guinea.

2002 ◽  
Vol 24 (2) ◽  
pp. 243 ◽  
Author(s):  
TE Heinsohn
Keyword(s):  
Papua New Guinea ◽  
Tropical Forests ◽  
New Guinea ◽  
Tropical Lowland ◽  
Tree Hollows ◽  
Lowland Forests ◽  
Cape York ◽  
The Common

THE common spotted cuscus Spilocuscus maculatus is a relatively large nocturnal arboreal possum with a preference for tropical lowland forests. Its distribution is centred on New Guinea, but extends to some adjacent landmasses, including a number of satellite islands and Cape York Peninsula in Australia (Flannery 1994; Winter and Leung 1995; Heinsohn 2000). It appears to be principally folivorous and partially frugivorous and forages in the canopy, subcanopy, and understorey of tropical forests, though it may venture to the ground to cross gaps. After a night of foraging, S. maculatus typically rests by day hidden amidst the thick foliage of the canopy, in liana tangles or thickets, and appears to be less dependent on, or less inclined to use tree hollows than some other possum species (Heinsohn 1998b, pers. obs.).

Selectivity for barramundi (Lates calcarifer) in the Fly River, Papua New Guinea: implications for managing gill-net fisheries on protandrous fishes

1998 ◽  
Vol 49 (6) ◽  
pp. 499 ◽  
Author(s):  
David A. Milton ◽  
David Die ◽  
Charles Tenakanai ◽  
Stephen Swales
Keyword(s):  
Papua New Guinea ◽  
Egg Production ◽  
Mesh Size ◽  
New Guinea ◽  
Lates Calcarifer ◽  
Gill Net ◽  
River Region ◽  
The Common ◽  
Fly River ◽  
Sexually Mature

Fishery-independent catch data from monofilament gill-nets (3.8–15.2 cm stretched mesh) were used to estimate the selectivity of each mesh size for the protandrous species barramundi, Lates calcarifer, in the Fly River region of Western Province, Papua New Guinea. These results were used with a range of life-history parameters to simulate the effects of fishing with meshes of three sizes common to the local fisheries (8.9, 10.2 and 15.2 cm) on (1) number of sexually mature females surviving to maximum age, (2) their total egg production and (3) number of mature males surviving to fertilize these eggs. Catches in most mesh sizes approximated a normal selection curve, and the mean and standard deviation of each curve were linearly related to mesh size. Juvenile and immature barramundi (<38 cm total length) were fully selected by the common mesh sizes used in the coastal subsistence and artisanal fisheries (7.6–10.2 cm) but these mesh sizes caught few sexually mature females. Population simulations showed that the number of females surviving to maximum age and their total egg production increased as mesh size was reduced. Reducing the mesh size to increase adult female escapement may be a better management strategy than increasing mesh sizes to improve recruitment.

scholarly journals Flood-induced Bridge Failures in Papua New Guinea

2019 ◽  
Vol 258 ◽  
pp. 03014
Author(s):  
Gibson Ali Holemba ◽  
Takashi Matsumoto
Keyword(s):  
Papua New Guinea ◽  
Average Rate ◽  
New Guinea ◽  
Field Investigation ◽  
Bridge Piers ◽  
Major Road ◽  
Recent Past ◽  
Common Causes ◽  
The Common ◽  
Bridge Failure

Papua New Guinea has been experiencing frequent bridge failures and collapses due to flooding rivers in the recent past. According to the records from Papua New Guinea Department of Works, it is estimated that over Two Hundred and Eighty (285) bridges, fords (causeways) and major culverts were damaged by flood action alone in the last five years between 2013-2017. That is approximately at an average rate of 57 bridges in a year. This result is very disturbing and as such this study was undertaken to assess and analyze the flood-induced bridge failure causes and offer applicable solutions. This study will report on the field investigation works and results derived from the twenty-one flood affected bridges in six different major road networks in three provinces of Papua New Guinea. Hence, it was observed in this study that substructure damages due to flooding account for seventy percent (70%) of the bridge damages while superstructure damages account for the thirty percent (30%). The common causes of flood-induced bridge failures were identified as local scour around bridge piers and abutments, contraction scours, sedimentation, debris, and log impact.

scholarly journals Endosymbiont Capture, a Repeated Process of Endosymbiont Transfer with Replacement in Trypanosomatids Angomonas spp.

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 702
Author(s):  
Tomáš Skalický ◽  
João M. P. Alves ◽  
Anderson C. Morais ◽  
Jana Režnarová ◽  
Anzhelika Butenko ◽  
...  
Keyword(s):  
Papua New Guinea ◽  
Common Ancestor ◽  
Phylogenetic Analyses ◽  
New Guinea ◽  
Bacterial Symbionts ◽  
Bacterial Genomes ◽  
Phylogenetic Relatedness ◽  
The Common ◽  
Multicellular Organisms

Trypanosomatids of the subfamily Strigomonadinae bear permanent intracellular bacterial symbionts acquired by the common ancestor of these flagellates. However, the cospeciation pattern inherent to such relationships was revealed to be broken upon the description of Angomonas ambiguus, which is sister to A. desouzai, but bears an endosymbiont genetically close to that of A. deanei. Based on phylogenetic inferences, it was proposed that the bacterium from A. deanei had been horizontally transferred to A. ambiguus. Here, we sequenced the bacterial genomes from two A. ambiguus isolates, including a new one from Papua New Guinea, and compared them with the published genome of the A. deanei endosymbiont, revealing differences below the interspecific level. Our phylogenetic analyses confirmed that the endosymbionts of A. ambiguus were obtained from A. deanei and, in addition, demonstrated that this occurred more than once. We propose that coinfection of the same blowfly host and the phylogenetic relatedness of the trypanosomatids facilitate such transitions, whereas the drastic difference in the occurrence of the two trypanosomatid species determines the observed direction of this process. This phenomenon is analogous to organelle (mitochondrion/plastid) capture described in multicellular organisms and, thereafter, we name it endosymbiont capture.

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