Screening of Submergence Tolerant Rice under Artificial Condition Based on Multiple Selection Indices

Soil salinity is one of the main factors limiting cereal productivity in worldwide agriculture. Exploitation of natural variation in local barley germplasm is an effective approach to overcome yield losses. Three gene pools of North African Hordeum vulgare L. grown in Tunisia, Algeria and Egypt were evaluated at the reproductive stage under control and saline conditions. Assessment of stress tolerance was monitored using morphological, yield-related traits and phenological parameters of reproductive organs showing significant genetic variation. High heritability and positive relationships were found suggesting that some traits associated with salt tolerance could be used as selection criteria. The phenotypic correlations revealed that vegetative traits including shoot biomass, tiller number and leaf number along with yield-related traits such as spike number, one spike dry weight, grain number/plant and grain number/spike were highly positively correlated with grain yield under saline conditions. Hence, these traits can be used as reliable selection criteria to improve barley grain yield. Keeping a higher shoot biomass and longer heading and maturity periods as well as privileged filling ability might contribute to higher grain production in barley and thus could be potential target traits in barley crop breeding toward improvement of salinity tolerance. Multiple selection indices revealed that salt tolerance trait index provided a better discrimination of barley landraces allowing selection of highly salt-tolerant and highly productive genotypes under severe salinity level. Effective evaluation of salt tolerance requires an integration of selection indices to successfully identify and characterize salt tolerant lines required for valuable exploitation in the management of salt-affected areas.

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Expected Genetic Contributions and Their Impact on Gene Flow and Genetic Gain

Genetics ◽

10.1093/genetics/153.2.1009 ◽

1999 ◽

Vol 153 (2) ◽

pp. 1009-1020 ◽

Cited By ~ 4

Author(s):

J A Woolliams ◽

P Bijma ◽

B Villanueva

Keyword(s):

Gene Flow ◽

Genetic Gain ◽

Overlapping Generations ◽

Predictive Accuracy ◽

Index Theory ◽

Previous Theory ◽

Selection Indices ◽

Breeding Groups ◽

Genetic Contributions

Abstract Long-term genetic contributions (ri) measure lasting gene flow from an individual i. By accounting for linkage disequilibrium generated by selection both within and between breeding groups (categories), assuming the infinitesimal model, a general formula was derived for the expected contribution of ancestor i in category q (μi(q)), given its selective advantages (si(q)). Results were applied to overlapping generations and to a variety of modes of inheritance and selection indices. Genetic gain was related to the covariance between ri and the Mendelian sampling deviation (ai), thereby linking gain to pedigree development. When si(q) includes ai, gain was related to E[μi(q)ai], decomposing it into components attributable to within and between families, within each category, for each element of si(q). The formula for μi(q) was consistent with previous index theory for predicting gain in discrete generations. For overlapping generations, accurate predictions of gene flow were obtained among and within categories in contrast to previous theory that gave qualitative errors among categories and no predictions within. The generation interval was defined as the period for which μi(q), summed over all ancestors born in that period, equaled 1. Predictive accuracy was supported by simulation results for gain and contributions with sib-indices, BLUP selection, and selection with imprinted variation.

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Comparison of selection indices to identify sorghum genotypes resistant to the spotted stemborer Chilo partellus (Lepidoptera: Noctuidae)

International Journal of Tropical Insect Science ◽

10.1017/s1742758411000105 ◽

2011 ◽

Vol 31 (1-2) ◽

pp. 38-51 ◽

Cited By ~ 9

Author(s):

B.U. Singh ◽

K.V. Rao ◽

H.C. Sharma

Keyword(s):

Chilo Partellus ◽

Selection Indices ◽

Sorghum Genotypes ◽

Lepidoptera Noctuidae

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Analysis of yield and oil from a series of canola breeding trials. Part II. Exploring variety by environment interaction using factor analysisThis article is one of a selection of papers from the conference “Exploiting Genome-wide Association in Oilseed Brassicas: a model for genetic improvement of major OECD crops for sustainable farming”.

Genome ◽

10.1139/g10-080 ◽

2010 ◽

Vol 53 (11) ◽

pp. 1002-1016 ◽

Cited By ~ 59

Author(s):

B.R. Cullis ◽

A.B. Smith ◽

C.P. Beeck ◽

W.A. Cowling

Keyword(s):

Pedigree Information ◽

Environment Interaction ◽

Correlation Matrices ◽

New Approach ◽

Genome Wide ◽

Selection Indices ◽

New Varieties ◽

Oilseed Brassicas ◽

Analytic Models ◽

Selection Of

Exploring and exploiting variety by environment (V × E) interaction is one of the major challenges facing plant breeders. In paper I of this series, we presented an approach to modelling V × E interaction in the analysis of complex multi-environment trials using factor analytic models. In this paper, we develop a range of statistical tools which explore V × E interaction in this context. These tools include graphical displays such as heat-maps of genetic correlation matrices as well as so-called E-scaled uniplots that are a more informative alternative to the classical biplot for large plant breeding multi-environment trials. We also present a new approach to prediction for multi-environment trials that include pedigree information. This approach allows meaningful selection indices to be formed either for potential new varieties or potential parents.

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On the Nature of the Cellular Elements Present in Milk. Part III. The Milk of Animals other than the Cow

Journal of Hygiene ◽

10.1017/s0022172400016545 ◽

1911 ◽

Vol 11 (1) ◽

pp. 97-104 ◽

Cited By ~ 1

Author(s):

R. Tanner Hewlett ◽

Sidney Villar ◽

Cecil Revis

Keyword(s):

General Consideration ◽

Milk Secretion ◽

High Cell ◽

Cell Counts ◽

Artificial Condition ◽

Definite Manner ◽

Blood Elements ◽

Great Stress ◽

Very High ◽

Stimulation Of

The general consideration of these results only tends to confirm the conclusions already arrived at. A uniform type of life evidently tends to a fairly uniform excretion of tissue cells from the udder. The case of Goat II also emphasises the effect of outside causes in increasing temporarily this excretion, while some of the samples of human milk show plainly that very high cell counts are not by any means necessarily connected with any diseased or disordered condition of the mammary gland.We again emphasise the view we have already stated, viz. that in the cow the udder must be looked upon as an organ which has by breeding and selection been brought to an artificial condition of milk secretion and that this has been accompanied by a stimulation of the tissues to cell proliferation and that this proliferation may quite easily be caused to become abnormally great, leading to the appearance of an increased number of cells in the secretion. In support of this view we lay great stress on the fact constantly noticed by us, viz. that when the cell count is high for any reason, the cells themselves are always well-defined, showing little signs of degeneration, and also stain in a much more characteristic and definite manner, a fact which is diffcult to explain if they are to be considered to be blood elements.

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Genetic variation and relationship of ultrasonic measures and carcass composition in Suffolk cross lambs

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200593089 ◽

1996 ◽

Vol 1996 ◽

pp. 111-111

Author(s):

V.C. Flamarique ◽

R.M. Lewis ◽

G. Simm

Keyword(s):

Genetic Variation ◽

Selection Criteria ◽

Live Weight ◽

Ultrasonic Measurement ◽

Carcass Composition ◽

Selection Indices ◽

Terminal Sire ◽

Relationship Of ◽

The Relationship

Excess fat in lamb is regarded as an important reason for less lamb meat being purchased by consumers. This has encouraged the development and use (particularly in Terminal Sire breeds) of selection indices that can identify animals that will sire leaner progeny. These indices usually include live weight and in vivo predictors of body composition, such as an ultrasonic measurement of muscle and fat depth, as selection criteria (Simm and Dingwall, 1989). But the usefulness of such in vivo measurements as predictors of carcass composition depends on the correlation between, and the variation in, live and carcass measures. The objectives of this study were to determine the strength of the relationship between ultrasound and dissection measures of carcass composition, and the degree of genetic variation in these measures, in crossbred progeny of Suffolk rams.

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