Genetic analysis of cold hardiness and dormancy in alfalfa

Genome ◽  
1987 ◽  
Vol 29 (1) ◽  
pp. 144-149 ◽  
Author(s):  
M. C. Perry ◽  
M. S. McIntosh ◽  
W. J. Wiebold ◽  
Mark Welterlen
Keyword(s):  
Medicago Sativa ◽  
Cold Hardiness ◽  
Plant Root ◽  
Specific Conductivity ◽  
Environmental Correlations ◽  
Mean Values ◽  
Combining Abilities ◽  
Fall Dormancy ◽  
Selection For ◽  
Fall Growth

Cold hardiness and fall dormancy in alfalfa (Medicago sativa L.) are positively associated, although this relationship is not always desirable for maximum production. The purpose of this study was to determine basic genetic information about cold hardiness and dormancy utilizing six parents differing in their cold hardiness and fall dormancy and their S0 and S1 progeny. A 6 × 6 diallel analysis was conducted to determine differences in general and specific combining abilities. Parent–offspring regression analyses were used to estimate heritabilities for cold hardiness and fall dormancy. Fall dormancy was measured as plant height 42 days after a final cut in September. Cold hardiness was measured using specific conductivity of exosmolyzed electrolytes of plant root tissues subjected to −8 °C. General combining abilities were significant for specific conductivity and height. Specific combining ability was also significant for specific conductivity. Mean values for S0 cross progeny were 11 to 13% higher than midparent values. Heritability estimates based on parent–offspring regression coefficients were 1.32 for specific conductivity and 0.72 for height.Significant positive phenotypic correlations were found for specific conductivity and fall growth for all generations except for height for S1 progeny. The correlations decreased with each successive generation. Genotypic correlations were positive, large, and increasing for each generation indicating large, negative, and decreasing environmental correlations. Linkage of these two traits is suggested. Selection for cold hardiness and fall growth would be rapid with proper breeding methods, but selection for high levels of both cold hardiness and fall growth would be difficult with the cultivars used in this study. Key words: cold hardiness, dormancy, alfalfa, Medicago sativa, conductivity, fall growth, phenotypic, genotypic.

FALL GROWTH AND WINTER SURVIVAL OF ALFALFA IN INTERIOR BRITISH COLUMBIA

1989 ◽  
Vol 69 (2) ◽  
pp. 491-499 ◽  
Author(s):  
DARRYL G. STOUT ◽  
JOHN W. HALL
Keyword(s):  
British Columbia ◽  
Low Temperature ◽  
Medicago Sativa ◽  
Cold Hardiness ◽  
Winter Survival ◽  
Temperature Growth ◽  
Usual Procedure ◽  
Medicago Sativa L ◽  
Selection Of ◽  
Fall Growth

Extensive winter injury, likely caused by cold damage, occurred in alfalfa (Medicago sativa L.) cultivar yield tests underway at Kamloops, British Columbia during the 1985–1986 winter. Fall yield of cultivars during the year of seeding was negatively correlated with their winter survival (r = − 0.92 in one trial with 20 cultivars or strains, and r = − 0.74 in a second study with 34 cultivars or strains). Use of fall yield to predict winter survival has the advantage over the usual procedure of measuring plant height in space-planted plots, in that both total annual yield and fall growth can be evaluated in a single study. This results in a major saving of costs. Six cultivar studies all revealed that in the interior of British Columbia spring-summer yield is positively correlated to fall yield (r = 0.24 to 0.72). For this reason, selection of a cultivar with low fall growth to obtain high winter survival is likely to result in selection of a cultivar with reduced spring-summer yield.Key words: Medicago sativa, alfalfa, low temperature growth, winter injury, cold hardiness

Genetic selection for nonstructural carbohydrates and its impact on other nutritive attributes of alfalfa ( Medicago sativa ) forage

2021 ◽  
Author(s):  
Annie Claessens ◽  
Marie Bipfubusa ◽  
Caroline Chouinard‐Michaud ◽  
Annick Bertrand ◽  
Gaëtan F. Tremblay ◽  
...  
Keyword(s):  
Medicago Sativa ◽  
Genetic Selection ◽  
Nonstructural Carbohydrates ◽  
Selection For

scholarly journals MEASURING BANK EFFICIENCY: DEA APPLICATION

2014 ◽  
Vol 20 (4) ◽  
pp. 739-757 ◽  
Author(s):  
Jelena Titko ◽  
Jelena Stankevičienė ◽  
Nataļja Lāce
Keyword(s):  
Banking Sector ◽  
Linear Regression Analysis ◽  
Analytical Data ◽  
Returns To Scale ◽  
Mean Values ◽  
Dea Model ◽  
Two Samples ◽  
Variables Selection ◽  
Measuring Efficiency ◽  
Selection For

The paper aims to improve the methodology of measuring efficiency of Latvian banks. Efficiency scores were calculated with application of non-parametric frontier technique Data Envelopment Analysis (DEA). Input-oriented DEA model under Variable Returns to Scale (VRS) assumption was used. Potential model variables were selected based on the intermediation and profitability approach. Fourteen alternative models with different inputs-outputs combinations were developed for the research purposes. To substantiate the variables selection for DEA model the received data was processed, using such methods, as correlation analysis, linear regression analysis, analysis of mean values, and two-samples Kolmogorov-Smirnov test. The research results assisted the authors in providing general recommendations about the variables selection for DEA application in the Latvian banking sector. The present research contributes to the existing analytical data on bank performance in Latvia. The empirical findings provide a background for further studies, in particular, the efficiency of Latvian banks could be analysed in the extended time period.

On Bayesian model selection for INGARCH models viatrans-dimensional Markov chain Monte Carlo methods

2021 ◽  
pp. 1471082X2110347
Author(s):  
Panagiota Tsamtsakiri ◽  
Dimitris Karlis
Keyword(s):  
Time Series ◽  
Model Selection ◽  
Bayesian Model ◽  
Linear Models ◽  
Simulation Experiment ◽  
Mean Values ◽  
The Past ◽  
Competing Models ◽  
Selection For ◽  
Log Linear

There is an increasing interest in models for discrete valued time series. Among them, the integer autoregressive conditional heteroscedastic (INGARCH) is a model that has found several applications. In the present article, we study the problem of model selection for this family of models. Namely we consider that an observation conditional on the past follows a Poisson distribution where its mean depends on its past mean values and on past observations. We consider both linear and log-linear models. Our purpose is to select the most appropriate order of such models, using a trans-dimensional Bayesian approach that allows jumps between competing models. A small simulation experiment supports the usage of the method. We apply the methodology to real datasets to illustrate the potential of the approach.

SELECTION FOR SEED SET IN NONINBRED AND PARTLY INBRED POPULATIONS OF ALFALFA

1977 ◽  
Vol 57 (3) ◽  
pp. 873-881 ◽  
Author(s):  
R. MICHAUD ◽  
T. H. BUSBICE
Keyword(s):  
Medicago Sativa ◽  
Seed Set ◽  
Exponential Model ◽  
Seed Setting ◽  
Medicago Sativa L ◽  
Selection For ◽  
Inbred Populations ◽  
The Relationship ◽  
Advanced Generation ◽  
Coefficient Of Inbreeding

Alfalfa (Medicago sativa L.) is a highly heterozygous cross-pollinating species, and most breeding efforts have been conducted on noninbred populations. The purpose of this study was to determine whether greater breeding progress could be made by selecting within partly inbred populations rather than within noninbred ones. One hundred and twenty F1 (noninbred) and 120 S1 (partly inbred) plants that were issued from crossing and selfing four alfalfa clones were evaluated for self-fertility. The most self-fertile 10% of the plants from each family were selected in each population. The selected plants within each level of inbreeding were intercrossed to produce an advanced generation in which the effectiveness of the selection was evaluated. Selection increased both self- and cross-fertility in the advanced generation. Selection was more effective at the F1 level than at the S1 level. Fertility was reduced drastically by inbreeding. The average self-fertility of the S1’s was only about 7% of the cross-fertility of their parental clones. An exponential model was proposed to describe the relationship between seed setting and the coefficient of inbreeding in the developing zygote. This model explained 95% of the variation among 11 unselected populations having differing levels of inbreeding.

Identification and selection for salt tolerance in lucerne (Medicago sativa L.)

1984 ◽  
Vol 35 (2) ◽  
pp. 239 ◽  
Author(s):  
CL Noble ◽  
GM Halloran ◽  
DW West
Keyword(s):  
Salt Tolerance ◽  
Medicago Sativa ◽  
Recurrent Selection ◽  
Leaf Damage ◽  
Shoot Number ◽  
Two Generations ◽  
Medicago Sativa L ◽  
Selection For ◽  
Efficiency Of Selection ◽  
Chloride Concentrations

Variation existed between plants of the lucerne (Medicago sativa L.) cultivar CUF 101 for dry matter production, shoot number and length, and leaf damage when grown for 70 days under 250 mM NaCl (15 h photoperiod, 20�C day, 10�C night). Salt tolerance evaluation using the criteria percentage leaf damage (percentage of total number of leaves with complete or partial necrosis) and length of the main shoot, isolated plants which showed salt tolerance of reasonably high heritability (h2=0.41). Two generations of recurrent selection for tolerance significantly increased the mean population tolerance without decreasing production under non-saline conditions. While both sodium and chloride concentrations of the shoot were lower in the tolerant than in less tolerant plants, chloride was more closely associated with salt tolerance than sodium. Sodium and chloride concentrations in the roots did not vary with the level of salt tolerance. No association of shoot and root potassium concentration with tolerance was evident. Selection for salt tolerance in lucerne plants using percentage leaf damage of less than 10% as the main criterion should give a rapid response to selection. The efficiency of selection may be increased if selection is based on the efficiency of chloride exclusion from the shoots and/or the level of chloride tolerated by the shoots prior to leaf damage becoming evident.

scholarly journals Genome-Wide Association Mapping and Genomic Selection for Alfalfa (Medicago sativa) Forage Quality Traits

PLoS ONE ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. e0169234 ◽  
Author(s):  
Elisa Biazzi ◽  
Nelson Nazzicari ◽  
Luciano Pecetti ◽  
E. Charles Brummer ◽  
Alberto Palmonari ◽  
...  
Keyword(s):  
Association Mapping ◽  
Medicago Sativa ◽  
Genomic Selection ◽  
Forage Quality ◽  
Genome Wide Association ◽  
Quality Traits ◽  
Genome Wide ◽  
Selection For

Alfalfa plant death during the summer versus the winter in interior British Columbia

1992 ◽  
Vol 72 (3) ◽  
pp. 931-936 ◽  
Author(s):  
Darryl G. Stout ◽  
S. N. Acharya ◽  
H. C. Huang ◽  
M. R. Hanna
Keyword(s):  
British Columbia ◽  
Verticillium Wilt ◽  
Winter Hardiness ◽  
Wilt Resistance ◽  
Verticillium Wilt Resistance ◽  
The Third ◽  
Fall Dormancy ◽  
The Relationship ◽  
Fall Growth

Single plants of 12 alfalfa (Mediccigo sativa L.) cultivars, chosen to represent a range of winter hardiness and resistance to verticillium wilt (Verticillium albo-atrum), were space planted to determine the time of plant death during the year. Plant mortality was assessed in spring and fall for three consecutive years. The relationship between plant survival during summer or winter and the cultivars’ resistance to verticillium wilt or fall growth was examined. During the first 2 yr of this field study, natural mortality during both summer and winter ranged from 1.0 to 2.1%. But by the third year an average of 9% of the plants died during the summer. Survival during the third summer was correlated (r = 0.76, P = 0.004) with the veritcillium wilt resistance measured using a greenhouse screening test, but was not correlated with fall growth of the cultivars. During the third winter, plant death for all cultivars averaged 67%. Survival of a cultivar during the winter was negatively correlated (r = −0.84, P = 0.001) with its fall growth, but not with its verticillium wilt resistance. These results indicate that programs to develop alfalfa cultivars with long-term persistence in the interior region of British Columbia should include both fall growth and verticillium wilt resistance in their selection criteria.Key words: Verticillium wilt, winter injury, fall dormancy, winter hardiness, stand persistence

Sign in / Sign up

Export Citation Format

Share Document