Evaluating cosmic coincidences in the context of astrophysical source populations

The use of in vivo haploid induction system makes the doubled haploid (DH) technology easier to adopt for the conventional maize breeders. However, despite having played an important role in the initial developmental phases of DH technology, Indian maize research has yet to harvest its benefits. Haploid Inducer Lines (HILs) developed by CIMMYT are being widely used in maize breeding programmes in many countries including India. There, however, is no published information on the efficiency of DH line production using CIMMYT HILs in Indian maize breeding programmes. In the present study, the efficiency of DH production using CIMMYT’s tropically adapted inducer line TAILP1 was investigated with eight source populations including two of sweet corn. The average haploid induction rate (HIR) of TAILP1 was 5.48% with a range of 2.01 to 10.03%. Efficiency of DH production ranged from 0.14 to 1.87% for different source populations with an average of 1.07%. The information generated will be useful for maize breeders intending to use DH technology for accelerated development of completely homozygous lines.

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Effect of captivity on morphology: negligible changes in external morphology mask significant changes in internal morphology

Royal Society Open Science ◽

10.1098/rsos.172470 ◽

2018 ◽

Vol 5 (5) ◽

pp. 172470 ◽

Cited By ~ 3

Author(s):

Stephanie K. Courtney Jones ◽

Adam J. Munn ◽

Phillip G. Byrne

Keyword(s):

Sexual Dimorphism ◽

Captive Breeding ◽

Morphological Changes ◽

External Morphology ◽

Wild Animals ◽

Internal Morphology ◽

In Captivity ◽

Two Generations ◽

Breeding Programmes ◽

Source Populations

Captive breeding programmes are increasingly relied upon for threatened species management. Changes in morphology can occur in captivity, often with unknown consequences for reintroductions. Few studies have examined the morphological changes that occur in captive animals compared with wild animals. Further, the effect of multiple generations being maintained in captivity, and the potential effects of captivity on sexual dimorphism remain poorly understood. We compared external and internal morphology of captive and wild animals using house mouse ( Mus musculus ) as a model species. In addition, we looked at morphology across two captive generations, and compared morphology between sexes. We found no statistically significant differences in external morphology, but after one generation in captivity there was evidence for a shift in the internal morphology of captive-reared mice; captive-reared mice (two generations bred) had lighter combined kidney and spleen masses compared with wild-caught mice. Sexual dimorphism was maintained in captivity. Our findings demonstrate that captive breeding can alter internal morphology. Given that these morphological changes may impact organismal functioning and viability following release, further investigation is warranted. If the morphological change is shown to be maladaptive, these changes would have significant implications for captive-source populations that are used for reintroduction, including reduced survivorship.

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Bioinvasions of the Medfly Ceratitis capitata: Source Estimation Using DNA Sequences at Multiple Intron Loci

Genetics ◽

10.1093/genetics/153.1.351 ◽

1999 ◽

Vol 153 (1) ◽

pp. 351-360 ◽

Cited By ~ 3

Author(s):

Neil Davies ◽

Francis X Villablanca ◽

George K Roderick

Keyword(s):

Population Structure ◽

Latin America ◽

Dna Sequences ◽

Ceratitis Capitata ◽

Fruit Fly ◽

Ecological Processes ◽

The Status ◽

Considerable Controversy ◽

Source Populations ◽

Traditional Population

Abstract The Mediterranean fruit fly, Ceratitis capitata, is a devastating agricultural pest that threatens to become established in vulnerable areas such as California and Florida. Considerable controversy surrounds the status of Californian medfly infestations: Do they represent repeated introductions or the persistence of a resident population? Attempts to resolve this question using traditional population genetic markers and statistical methods are problematic because the most likely source populations in Latin America were themselves only recently colonized and are genetically very similar. Here, significant population structure among several New World medfly populations is demonstrated through the analysis of DNA sequence variation at four intron loci. Surprisingly, in these newly founded populations, estimates of population structure increase when measures of subdivision take into account the relatedness of alleles as well as their frequency. A nonequilibrium, likelihood-based statistical test that utilizes multilocus genotypes suggests that the sole medfly captured in California during 1996 was introduced from Latin America and was less likely to be a remnant of an ancestral Californian population. Many bioinvasions are hierarchical in nature, consisting of several sequential or overlapping invasion events, the totality of which can be termed a metainvasion. Phylogenetic data from multilocus DNA sequences will be vital to understanding the evolutionary and ecological processes that underlie metainvasions and to resolving their constituent levels.

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GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey III: South Galactic Pole data release

Publications of the Astronomical Society of Australia ◽

10.1017/pasa.2021.5 ◽

2021 ◽

Vol 38 ◽

Author(s):

T. M. O. Franzen ◽

N. Hurley-Walker ◽

S. V. White ◽

P. J. Hancock ◽

N. Seymour ◽

...

Keyword(s):

Large Scale ◽

Angular Resolution ◽

Beam Model ◽

Spectral Variability ◽

Extragalactic Source ◽

Automated Algorithm ◽

Data Release ◽

Murchison Widefield Array ◽

Source Populations ◽

One Year

Abstract We present the South Galactic Pole (SGP) data release from the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey. These data combine both years of GLEAM observations at 72–231 MHz conducted with the Murchison Widefield Array (MWA) and cover an area of 5 113 $\mathrm{deg}^{2}$ centred on the SGP at $20^{\mathrm{h}} 40^{\mathrm{m}} < \mathrm{RA} < 05^{\mathrm{h}} 04^{\mathrm{m}}$ and $-48^{\circ} < \mathrm{Dec} < -2^{\circ} $ . At 216 MHz, the typical rms noise is ${\approx}5$ mJy beam–1 and the angular resolution ${\approx}2$ arcmin. The source catalogue contains a total of 108 851 components above $5\sigma$ , of which 77% have measured spectral indices between 72 and 231 MHz. Improvements to the data reduction in this release include the use of the GLEAM Extragalactic catalogue as a sky model to calibrate the data, a more efficient and automated algorithm to deconvolve the snapshot images, and a more accurate primary beam model to correct the flux scale. This data release enables more sensitive large-scale studies of extragalactic source populations as well as spectral variability studies on a one-year timescale.

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R1-nj expression in parental inbreds as a predictor of amenability of maize hybrids to R1-nj-based doubled haploid development

Indian Journal of Genetics and Plant Breeding (The) ◽

10.31742/ijgpb.79.4.5 ◽

2020 ◽

Vol 79 (04) ◽

Author(s):

R. K. Khulbe ◽

A. Pattanayak ◽

Vivek Panday

Keyword(s):

Doubled Haploid ◽

Current Method ◽

Distinct Pattern ◽

Complex Nature ◽

Maize Breeding ◽

Early Maturity ◽

Haploid Inducer ◽

Source Populations ◽

Phenotype Expression

The current method of doubled haploid (DH) development in maize involves in vivo production of haploids using R1-njbased haploid inducer lines that upon use as male render a small fraction of seed in the pollinated female ears haploid. Identification of haploid seed relies on R1-nj marker expression in the endosperm and embryo, and the degree of its expression determines efficiency of DH development process. In the present study, R1-nj expression in the endosperm was characterized in crosses of CIMMYT’s R1-nj-based haploid inducer TAILP1 with a set comprising 18 early maturity hybrids and their 23 parental inbreds. Kernel colour inhibition was observed only in a small proportion of the hybrids and inbreds. Comparison of R1-nj expression in the hybrids and their parental inbreds revealed a distinct pattern, which may be useful in identifying source populations and/or determining parental constituents for synthesizing source populations with predicted amenability to doubled haploid development using R1-nj-based haploid inducers. However, deviation from the pattern was noted in hybrids involving inbreds with higher degree of colour inhibition, which suggests complex nature of R1-nj phenotype expression and necessitates further investigation involving larger sets of germplasm for dissecting the role of maternal and paternal genetic factors in determining R1-nj phenotype expression. The hybrids found exhibiting complete kernel anthocyanin expression in present study can be used directly as source populations for DH development using R1-nj based haploid inducers. Besides, since the inbreds used in the study have originated from and/or are accessible to CGIAR/NARS maize breeding programmes, the information on their kernel anthocyanin expression can be helpful in selection of source populations or generating new source populations amenable for DH development using R1-nj based haploid inducers.

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The X-ray source populations of the magellanic clouds

10.1063/1.1434659 ◽

2001 ◽

Author(s):

F. Haberl

Keyword(s):

Magellanic Clouds ◽

X Ray ◽

Source Populations

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Highly variable COI haplotype diversity between three species of invasive pest fruit fly reflects remarkably incongruent demographic histories

10.1101/742007 ◽

2019 ◽

Author(s):

Camiel Doorenweerd ◽

Michael San Jose ◽

Norman Barr ◽

Luc Leblanc ◽

Daniel Rubinoff

Keyword(s):

Haplotype Diversity ◽

Fruit Fly ◽

Coi Gene ◽

Invasive Pest ◽

Pest Species ◽

Invasion Pathways ◽

Geographic Ranges ◽

Bactrocera Correcta ◽

Invasive Pest Species ◽

Source Populations

AbstractDistance decay principles predict that species with larger geographic ranges would have greater intraspecific genetic diversity than more restricted species. However, invasive pest species may not follow this prediction, with confounding implications for tracking phenomena including original ranges, invasion pathways and source populations. We sequenced an 815 base-pair section of the COI gene for 441 specimens of Bactrocera correcta, 214 B. zonata and 372 Zeugodacus cucurbitae; three invasive pest fruit fly species with overlapping hostplants. For each species, we explored how many individuals would need to be included in a study to sample the majority of their haplotype diversity. We also tested for phylogeographic signal and used demographic estimators as a proxy for invasion potency. We find contrasting patterns of haplotype diversity amongst the species, where B. zonata has the highest diversity but most haplotypes were represented by singletons; B. correcta has ∼7 dominant haplotypes more evenly distributed; Z. cucurbitae has a single dominant haplotype with closely related singletons in a ‘star-shape’ surrounding it. We discuss how these differing patterns relate to their invasion histories. None of the species showed meaningful phylogeographic patterns, possibly due to gene-flow between areas across their distributions, obscuring or eliminating substructuring.

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Determining source populations of newly identified cases of chronic wasting disease in white‐tailed deer

The FASEB Journal ◽

10.1096/fasebj.26.1_supplement.1035.6 ◽

2012 ◽

Vol 26 (S1) ◽

Author(s):

Michelle L. Green ◽

Mary Beth Manjerovic ◽

Nohra E. Mateus-Pinilla ◽

Amy C. Kelly ◽

Paul Shelton ◽

...

Keyword(s):

Chronic Wasting Disease ◽

Wasting Disease ◽

Source Populations

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