scholarly journals Ancestral Contributions to Roasted Peanut Attribute1

1995 ◽  
Vol 22 (1) ◽  
pp. 42-48 ◽  
Author(s):  
T. G. Isleib ◽  
H. E. Pattee ◽  
F. G. Giesbrecht

Abstract Estimates of broad-sense heritability for roasted flavor attribute of peanut (Arachis hypogaea L.) range from 9 to 24% on a single-plot basis. Response to selection is determined by the narrow-sense heritability, calculated from estimates of additive genetic variance which are not available for this trait. One way to assess the additive component of genetic variation is to determine how much of the total phenotypic variation can be predicted from genetic contributions of ancestors of the individuals measured. From 1986 to 1991, samples of 128 peanut cultivars and breeding lines were obtained from peanut research programs representing the three major production areas in the U.S. Samples were roasted to a nearly common color, ground into paste, and assessed for roasted flavor and fruity attribute by a trained sensory panel. CIELAB L* color was also measured for use as a covariate in statistical analysis to adjust for small differences in color. The sum of squares associated with the 128 genotypes accounted for 11% of the total phenotypic variation. Ancestry of the lines was traced back to 47 progenitors for which no further pedigree information was available. Eight progenitors made ancestral contributions that were linearly dependent on the other 39. Ancestral effects accounted for 53% of the genotypic variation, i.e., 6% of the phenotypic variation. Despite shortcomings of this 6% figure as an estimate of narrow-sense heritability for roasted flavor, no other estimates are extant. The residual (nonadditive) variation among genotypes after accounting for ancestral (additive) effects was highly significant. Multiple regression model-building techniques were used to identify 13 ancestors exerting significant effects on roasted flavor. Jenkins Jumbo, F231 (a cross of Dixie Giant with Small White Spanish 3x-2), and Improved Spanish 2B were the only ancestors among the 13 that were common to 40 or more of the 128 lines tested. Jenkins Jumbo was the single most important ancestor, exerting a negative effect on flavor (b = −1.25±0.19). Its progeny would be expected to have roast flavor scores reduced by |b|/2 = 0.62 units and grandprogeny by |b|/4 = 0.31 units. All but four of the 13 ancestors deemed important had deleterious effects on flavor.

2003 ◽  
Vol 30 (1) ◽  
pp. 64-66 ◽  
Author(s):  
T. G. Isleib ◽  
H. E. Pattee ◽  
F. G. Giesbrecht

Abstract The sweet, bitter and roasted peanut attributes of roasted peanut (Arachis hypogaea L.) flavor have been shown to be heritable traits. Previous research has estimated broad-sense heritability (H) and breeding values of numerous peanut cultivars and breeding lines for these attributes, but no study has estimated narrow-sense heritability (h2) in a specific population derived through hybridization and inbreeding. A population of 120 F3-derived families was developed without selection from the cross of NC 7/NC Ac 18431, a virginia-type line identified in 1990 as having a good flavor profile. The parents and F3:5 families were grown at two locations in North Carolina in 1995. SMK samples from each plot were roasted, ground to paste, tasted by a sensory panel, and scored for roasted peanut, sweet, bitter and astringent attributes. Additive and nonadditive genetic variances were estimated by equating variances among F2-derived families and among F3-derived families within F2-derived families to genetic covariances among inbred relatives. Regardless of whether the genetic model included dominance or additive-by-additive epistasis, the estimates of additive genetic variance for flavor attributes were small compared to those for nonadditive genetic variance. Narrow-sense heritability in the F2 generation was estimated at 0 for roasted peanut and astringent, 0.02 to 0.04 for sweet, and 0.01 to 0.03 for bitter, depending on the model used. Because of the low values of h2, which are specific to this population, gain from selection in early generations is expected to be limited within this population. Selection in this population should be practiced in late generations. Other parents have been identified whose crosses should produce greater improvement in sensory quality than can be expected from the NC 7 / NC Ac 18431 population.


HortScience ◽  
1990 ◽  
Vol 25 (2) ◽  
pp. 224-226 ◽  
Author(s):  
A.B. Herriott ◽  
F.L. Haynes ◽  
P.B. Shoemaker

Heritability of resistance to early blight disease in potatoes (Solarium tuberosum L.) incited by Alternaria solani (En. & Martin) Ser. was estimated in tetraploid × diploid crosses. Susceptible tetraploid cultivars and breeding lines were the female parents. Diploids that produced a high proportion of first-division restitution (FDR) gametes and possessed different levels of early blight resistance were the male parents. Tubers from seedlings that resulted from the tetraploid × diploid crosses were planted in a field and artificially inoculated with spores of Alternaria solani. Resistance was measured as the slope (r) of the regression of the logit of the percent defoliation of each plant vs. time. Higher r values indicated lower resistance. Mean r values ranged from 0.123 to 0.157 for the tetraploid parents, and from 0.054 to 0.116 for the diploid parents. Mean r values for the tetraploid × diploid crosses were intermediate, ranging from 0.077 to 0.143. Narrow-sense heritability (h2) was 0.815. The partial correlation coefficient between r and mean maturity values was – 0.2086.


2017 ◽  
Author(s):  
Luke M. Evans ◽  
Rasool Tahmasbi ◽  
Matthew Jones ◽  
Scott I. Vrieze ◽  
Gonçalo R. Abecasis ◽  
...  

ABSTRACTHeritability is a fundamental parameter in genetics. Traditional estimates based on family or twin studies can be biased due to shared environmental or non-additive genetic variance. Alternatively, those based on genotyped or imputed variants typically underestimate narrow-sense heritability contributed by rare or otherwise poorly-tagged causal variants. Identical-by-descent (IBD) segments of the genome share all variants between pairs of chromosomes except new mutations that have arisen since the last common ancestor. Therefore, relating phenotypic similarity to degree of IBD sharing among classically unrelated individuals is an appealing approach to estimating the near full additive genetic variance while avoiding biases that can occur when modeling close relatives. We applied an IBD-based approach (GREML-IBD) to estimate heritability in unrelated individuals using phenotypic simulation with thousands of whole genome sequences across a range of stratification, polygenicity levels, and the minor allele frequencies of causal variants (CVs). IBD-based heritability estimates were unbiased when using unrelated individuals, even for traits with extremely rare CVs, but stratification led to strong biases in IBD-based heritability estimates with poor precision. We used data on two traits in ~120,000 people from the UK Biobank to demonstrate that, depending on the trait and possible confounding environmental effects, GREML-IBD can be applied successfully to very large genetic datasets to infer the contribution of very rare variants lost using other methods. However, we observed apparent biases in this real data that were not predicted from our simulation, suggesting that more work may be required to understand factors that influence IBD-based estimates.


2009 ◽  
Vol 58 (1-6) ◽  
pp. 292-300
Author(s):  
Y. H. Weng ◽  
Y. S. Park ◽  
D. Simpson ◽  
T. J. Mullin

AbstractGenetic gains based on a genetic test using clonal replicates were compared to those based on a test using seedlings at the same gene diversity and testing effort levels using POPSIM™ Simulator. Three testing and deployment strategies targeting for white spruce (P. glauca [Moench] Voss) and black spruce (P. mariana (Mill.) B.S.P.) in New Brunswick were compared: seedling test with clonal seed orchard deployed as seedlings (CSO_ST), clonally replicated test with clonal seed orchard deployed as seedlings (CSO_CRT), and clonally replicated test deployed as a clone mix (MVF). The breeding populations (BP) were formed by balanced within-family selection and the production populations (PP) were selected by strong restriction on relatedness, i.e., no parent in common. Compared to the seedling test, the clonally replicated test resulted in faster accumulation of additive effects but quicker loss of additive variance in the BP, and this is particular true in the case of lower narrow-sense heritability or less non-additive genetic variance. The quicker loss in BP additive variance was overcompensated for by its faster accumulation in BP additive effect, resulting in higher gain in the clonally replicated test based PPs. Compared to the CSO_ST, the gain superiority of the CSO_CRT increased with generations, decreasing narrow-sense heritability or reducing the amount of non-additive variance. Implementing MVF was the most effective in terms of gain in most simulated cases and its superiority over the CSO_ST increased with generations, decreasing narrowsense heritability, or increasing non-additive genetic variance. Overall results demonstrated significant advantages of using clonally replicated test both for BP advancement and PP selection in most of the scenarios, suggesting that clonally replicated test should be incorporated into current spruce breeding strategies.


Genome ◽  
2017 ◽  
Vol 60 (7) ◽  
pp. 572-580 ◽  
Author(s):  
Rong-Cai Yang

Narrow-sense heritability (portion of the total phenotypic variation attributable to additive genetic effect, h2) is a critical parameter in plant breeding and genetics, but its estimation is difficult for populations with unknown pedigree information. This study applied a marker-based linear mixed model (LMM) analysis to estimate narrow-sense heritability and its seven functional components corresponding to SNPs in coding and noncoding regions for each of 107 flowering, defense, ionomics, and developmental traits in an Arabidopsis (Arabidopsis thaliana) population of 199 inbred lines with unknown genetic relatedness. Genetic relationship matrix (GRM) based on 214 051 SNPs and component GRMs based on seven subsets of SNPs were computed for LMM estimation of h2 and functional components contributing to h2, respectively. The h2 estimates for flowering traits were higher than those for defense, ionomics, and developmental traits, supporting a general view that the fitness-related traits have lower heritabilities than other traits. The function component owing to SNPs in coding (exon) regions was the least contributor to h2. Our LMM analysis provides an opportunity to gain a comprehensive view on heritability and its functional components for populations with unknown structure but with genome-wide DNA markers.


1976 ◽  
Vol 18 (3) ◽  
pp. 419-427 ◽  
Author(s):  
D. R. Sampson ◽  
I. Tarumoto

Twenty-eight progenies with their eight parent cultivars of Avena saliva L. (2n = 6x = 42) were grown in F1, F2 and F3 in separate years; the F1 as spaced plants, the F2 and F3 as dense seeded populations. Additive genetic variance constituted most of the phenotypic variance of eight traits (heading date, plant height, stem diameter, grain yield and four components of yield) according to a Griffing Method 4, Model II analysis. Similarly, additive × year interactions were more important than nonadditive × year interactions. A Hayman-Jinks analysis of the same material but with the parents included showed that the additive component was 2 to 16 times larger than the dominance components in the F1 However in the F2 and F3 the dominance components became larger than the additive components for most traits instead of declining in importance as expected. Further, tests of fit to the hypotheses underlying the Hayman-Jinks analysis were negative in 8 of 24 cases. It is postulated that these discrepancies result from epistatic variance which caused an upward bias in the dominance estimates. The calculation and uses of two estimates of narrow-sense heritability are discussed.


2003 ◽  
Vol 13 (3) ◽  
pp. 241-247 ◽  
Author(s):  
Lauren Gerard Koch ◽  
Steven L. Britton

Creation of generalized genetic models for low and high sensorimotor capacity would be important tools for resolution of this complex trait. As proof-of-principle we estimated phenotypic variation and narrow-sense heritability (h2) of sensorimotor capacity in 19 families of genetically heterogeneous N:NIH rats and in 11 strains of inbred rats. Sensorimotor capacity was defined as the time a rat remained on an accelerating rotorod. N:NIH rats recorded variation in rotorod scores that ranged from 3- to 7-fold. The value of h2, estimated from offspring-parent regression across one generation, was 0.68 for females and 0.74 for males in N:NIH rats. In inbred rats, h2 was estimated by partitioning phenotypic variation into additive genetic and environmental components and averaged 0.39 in females and 0.48 in males. These results demonstrate a heritable component to sensorimotor capacity sufficient for success in developing contrasting genetic models by divergent artificial selection in rats.


2020 ◽  
Author(s):  
Fatemeh Pirnajmedin ◽  
Mohammad Mahdi Majidi ◽  
Mohammad Hadi Taleb ◽  
Sayed Ali Mohammad Mirmohammady Maibody

Abstract Background: The genetic basis and variability of persistence and summer dormancy and their association with forage production traits has been less investigated in tall fescue. Results: High genotypic variation was found for all the measured traits in both parental genotypes and half-sib families. Incomplete summer dormancy was found for most of the evaluated genotypes. Summer dormancy index were negatively correlated with forage production and yield related traits. Half-sib families had higher persistence than parental genotypes, which can be due to the heterosis expression in progenies. Moderate narrow-sense heritability for persistence indicates that both additive and dominant gene action may play a role in the expression of this trait. Yield-related traits and summer dormancy showed moderate to high estimates of narrow sense heritability (0.63-0.73) indicates additive gene action for these traits. This suggest phenotypic recurrent selection can be successful to achieve genetic progress. Conclusion: In conclusion, our results can enhance the knowledge of inheritance of summer dormancy and related traits which would be useful for future genetic studies. Based on the general combining ability and application of multivariate analysis, preferable genotypes for forage use (such as 21M and 1E) and turf application (such as 17M and 4E) were identified for future programs.


1971 ◽  
Vol 13 (4) ◽  
pp. 864-872 ◽  
Author(s):  
D. R. Sampson

The oat cultivate 'Dorval', 'Kelsey', 'Stormont', 'Orbit', 'Goodfield', 'Tyler' and 'Egdolon' and two numbered lines were crossed in a 3 × 6 factorial design. F1's, F2's and bullied F2 progenies were grown in successive years at seeding rates of 2.7, 9.5 and at the commercial rare of 76 Kg/ha, respectively; the F1's in irrigated cages, the F2's and F3's in nonirrigated fields. Additive genetic variance was the most important component of the phenotypic variances among progenies. Major differences occurred between the F1's and F2's, but the F2's and F3's agreed closely. The percentages of additive variance (narrow sense heritability) for the joint F2, F3 analyses were: height (91); heading date (87); seed weight (74); yield per panicle (71); seeds per panicle (63); panicle number (58); stem diameter (55); plot yield (52). Important nonadditive variance was present in the F2, F3 data for plot yield (17%), stem diameter (15%) and seed weight (12%). All traits were positively correlated with each other in the F1's. Correlations were weaker in the F2 and F3 and reversed for panicle number. Seed weight showed the least correlation with other traits. These results are discussed from the practical viewpoint of combining strong straw with high grain yield. The usefulness of selecting for seed weight and panicle yield to improve plot yield is underlined.


HortScience ◽  
1990 ◽  
Vol 25 (11) ◽  
pp. 1357F-1358
Author(s):  
Yiran Yu ◽  
James Harding ◽  
Thomas Byrne

Genetic components of variance and heritability of flowering time were estimated for five generations of the Davis Populationof Gerbera hybrids, Composite, Estimates of narrow-sense heritability averaged 0.50 and broad-sense heritability averaged 0.77 using the NCII design. Narrow-sense heritability was also estimated with two models of parent-offspring regression, resulting in average heritability of 0.49 and 0.51. Estimates of components of variance indicated that the major genetic effect controlling flowering time is additive. However, the dominance component accounted for 28% of the total variance; the environmental component was only 23%. Flowering time is negatively correlated with cut-flower yield. The phenotypic coefficient was –0.34; genetic correlations were –0.47 when estimated from the NCII design, and –0.72 when estimated from the parent-off-spring method. A practical model was constructed to assess the efficiency of indirect selection for cut-flower yield using flowering time as a marker trait. The advantages of indirect selection accruing from increased population size and reduced generation time are discussed.


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