STRAWBERRY BREEDING AND GENETICS RESEARCH IN NORTH WEST EUROPE

2014 ◽  
pp. 107-111 ◽  
Author(s):  
D.W. Simpson
Keyword(s):  
North West ◽  
Genetics Research ◽  
Breeding And Genetics ◽  
Strawberry Breeding

scholarly journals Image-based Phenotyping and Genetic Analysis of Potato Skin Set and Color

2019 ◽  
Author(s):  
Maria V. Caraza-Harter ◽  
Jeffrey B. Endelman
Keyword(s):  
Skin Color ◽  
Principal Component ◽  
Breeding Lines ◽  
Genetics Research ◽  
Single Location ◽  
Red Color ◽  
New Varieties ◽  
Potato Skin ◽  
Breeding And Genetics ◽  
Early Harvest

ABSTRACTImage-based phenotyping offers new opportunities for fast, objective, and reliable measurement for breeding and genetics research. In the current study, image analysis was used to quantify potato skin color and skin set, which are critical for the marketability of new varieties. A set of 15 red potato varieties and advanced breeding lines was evaluated over two years at a single location, with two harvest times in the second year. After mechanical harvest and grading, 7-8 representative tubers per plot were photographed, and the photos were analyzed with ImageJ to measure skinning (as % surface area) and skin color using the Hue, Chroma and Lightness (HCL) representation. The plot-based heritability was consistently high (> 0.77) across traits and environments; the genetic correlation between environments was also high, ranging from 0.81 to 0.98. Significant increases in Lightness and Chroma, as well as a decrease in skinning, were observed at the late compared to early harvest, while the opposite trends for color were observed after six weeks of storage. The three color traits were unexpectedly collinear in this study, with the first principal component explaining 86% of the variation. This result may reflect the physiology of red color in potato, but the highly selected nature of the 15 genotypes may also be a factor. Image-based phenotyping offers new opportunities to advance genetic gain and understanding for tuber appearance traits that have been difficult to precisely measure in the past.

M6: A Diploid Potato Inbred Line for Use in Breeding and Genetics Research

2014 ◽  
Vol 8 (2) ◽  
pp. 195-199 ◽  
Author(s):  
S. H. Jansky ◽  
Y. S. Chung ◽  
P. Kittipadukal
Keyword(s):  
Inbred Line ◽  
Diploid Potato ◽  
Genetics Research ◽  
Breeding And Genetics

scholarly journals Douglas Scott Falconer. 10 March 1913 – 23 February 2004

2005 ◽  
Vol 51 ◽  
pp. 119-133
Author(s):  
John C. Bowman
Keyword(s):  
Quantitative Genetics ◽  
Mouse Genome ◽  
Animal Breeding ◽  
Andrews University ◽  
Gene Linkage ◽  
Genetics Research ◽  
Mouse Mutants ◽  
Research And Teaching ◽  
Research Organisation ◽  
Breeding And Genetics

Douglas Scott Falconer obtained a first–class honours degree in Zoology at St Andrews University followed by a PhD at Cambridge for research on wireworms. He then worked with R. A. (later Sir Ronald) Fisher FRS, as a prelude to joining the ARC Genetics Section of its Animal Breeding and Genetics Research Organisation at Edinburgh University. There he spent the rest of his career, later becoming Head of Unit and a personal professor in the university.His research interests fell into three main categories: the formal genetics of the mouse, quantitative genetics, and the genetics of human diseases. His work on mouse mutants and gene linkage was a major contribution to mapping the mouse genome, and his research in quantitative genetics produced theoretical and practical findings that have been of much benefit to animal breeders and to human geneticists as well as to the understanding of traits of complex inheritance.From his research and teaching he developed his acclaimed textbook Introduction to quantitative genetics , which ran to four editions in 36 years. The book is used as a foundation text worldwide.Douglas was much admired as a stimulating and innovative scientist, a considerate and polite colleague, and family gentleman.

Recent progress in strawberry breeding and genetics at NIAB EMR, East Malling, UK

2021 ◽  
pp. 169-174
Author(s):  
A.B. Whitehouse ◽  
A.W. Johnson ◽  
H.M. Cockerton ◽  
C.F. Nellist ◽  
B. Li ◽  
...  
Keyword(s):  
Recent Progress ◽  
Breeding And Genetics ◽  
Strawberry Breeding

scholarly journals Extending long-range phasing and haplotype library imputation algorithms to very large and heterogeneous datasets

2018 ◽  
Author(s):  
Daniel Money ◽  
David Wilson ◽  
Janez Jenko ◽  
Gregor Gorjanc ◽  
John M. Hickey
Keyword(s):  
Long Range ◽  
Missing Values ◽  
Computational Cost ◽  
Simulated Dataset ◽  
Nucleotide Polymorphisms ◽  
Single Chromosome ◽  
Genetics Research ◽  
Heterogeneous Datasets ◽  
Breeding And Genetics ◽  
Surrogate Parents

AbstractBackgroundThis paper describes the latest improvements to the long-range phasing and haplotype library imputation algorithms that enable them to successfully phase both datasets with one million individuals and datasets genotyped using different sets of single nucleotide polymorphisms (SNPs). Previous publicly available implementations of long-range phasing could not phase large datasets due to the computational cost of defining surrogate parents by exhaustive all-against-all searches. Further, both long-range phasing and haplotype library imputation were not designed to deal with large amounts of missing data, which is inherent when using multiple SNP arrays.MethodsHere, we developed methods which avoid the need for all-against-all searches by performing long-range phasing on subsets of individuals and then combing results. We also extended long-range phasing and haplotype library imputation algorithms to enable them to use different sets of markers, including missing values, when determining surrogate parents and identifying haplotypes. We implemented and tested these extensions in an updated version of our phasing software AlphaPhase.ResultsA simulated dataset with one million individuals genotyped with the same set of 6,711 SNP for a single chromosome took two days to phase. A larger dataset with one million individuals genotyped with 49,579 SNP for a single chromosome took 14 days to phase. The percentage of correctly phased alleles at heterozygous loci was respectively 90.5% and 90.0% for the two datasets, which is comparable to the accuracy achieved with previous versions of AlphaPhase on smaller datasets.The phasing accuracy for datasets with different sets of markers was generally lower than that for datasets with one set of markers. For a simulated dataset with three sets of markers 2.8% of alleles at heterozygous positions were phased incorrectly whereas the equivalent figure with one set of markers was 0.6%.ConclusionsThe improved long-range phasing and haplotype library imputation algorithms enable AlphaPhase to quickly and accurately phase very large and heterogeneous datasets. This will enable more powerful breeding and genetics research and application.

scholarly journals Performance of Muscadine Grape Cultivars in Southern Mississippi

2008 ◽  
Vol 18 (4) ◽  
pp. 726-733 ◽  
Author(s):  
Stephen J. Stringer ◽  
Donna A. Marshall ◽  
Blair J. Sampson ◽  
James M. Spiers
Keyword(s):  
Mississippi State University ◽  
State University ◽  
Fresh Market ◽  
Vitis Rotundifolia ◽  
Genetics Research ◽  
Cultivar Selection ◽  
Selection Decisions ◽  
Muscadine Grape ◽  
High Yields ◽  
Breeding And Genetics

A study was conducted at the Mississippi State University Agricultural and Forestry Experiment Station (MAFES) McNeil Unit in southern Mississippi to identify promising muscadine grape (Vitis rotundifolia) germplasm for use as parents in the breeding and genetics research program and to develop information on performance for use by growers in the region for cultivar selection decisions. The vineyard was first established in 1992 and was expanded in 1994. Cultivars were evaluated in 2001, 2002, and 2006 for their performance and were found to differ in vigor, resistance to diseases, yield, and fruit quality. Cultivars suitable for winemaking that performed well included Carlos, Doreen, Magnolia, Noble, Regale, Sterling, and Welder. Cultivars intended for the fresh market that produced high yields and high-quality fruit included Alachua, Black Beauty, Darlene, Fry, Ison, Janebell, Nesbit, Polyanna, Sweet Jenny, Summit, and Tara. ‘Dixie’, a multipurpose cultivar, ‘Eudora’, a newly released fresh-market cultivar, and ‘Southern Home’, a multipurpose cultivar with enhanced ornamental value, also performed well at this location.

Electron Microscopic Examination of a Transplantable Rat Mammary Carcinoma

1968 ◽  
Vol 26 ◽  
pp. 20-21
Author(s):  
S. Shirahama ◽  
G. C. Engle ◽  
R. M. Dutcher
Keyword(s):  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Electron Microscopic Examination ◽  
Undifferentiated Carcinoma ◽  
Uranyl Acetate ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
North West ◽  
X Irradiation ◽  
Tissue Specimens

A transplantable carcinoma was established in North West Sprague Dawley (NWSD) rats by use of X-irradiation by Engle and Spencer. The tumor was passaged through 63 generations over a period of 32 months. The original tumor, an adenocarcinoma, changed into an undifferentiated carcinoma following the 19th transplant. The tumor grew well in NWSD rats of either sex at various ages. It was invariably fatal, causing death of the host within 15 to 35 days following transplantation.Tumor, thymus, spleen, and plasma from 7 rats receiving transplants of tumor at 3 to 9 weeks of age were examined with an electron microscope at intervals of 8, 15, 22 and 30 days after transplantation. Four normal control rats of the same age were also examined. The tissues were fixed in glutaraldehyde, postfixed in osmium tetroxide and embedded in Epon. The plasma was separated from heparanized blood and processed as previously described for the tissue specimens. Sections were stained with uranyl acetate followed by lead citrate and examined with an RCA EMU-3G electron microscope.

SEM and TEM observations of sperm development in the testis of the freshwater fish Oreochromis mossambicus

1990 ◽  
Vol 48 (3) ◽  
pp. 58-59
Author(s):  
Daryl A. Cornish ◽  
George L. Smit
Keyword(s):  
Morphological Characteristics ◽  
Oreochromis Mossambicus ◽  
Breeding Cycle ◽  
Limited Information ◽  
North West ◽  
The North ◽  
Sem And Tem ◽  
Sperm Development ◽  
Ultrastructural Characteristics ◽  
The University

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.

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