Standard Errors of Heritability Estimates Calculated from Variance Component Analysis af a Two-Way Classification

Jensen, E.L.; Barr, G.R.

doi:10.2527/jas1971.3261069x

Cited by 9 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The heritability obtained in our study is likely to allow selection (Eriksson et al 2013;Alcaide et al 2019). Nevertheless, these results must be taken with caution due to the low number of genotypes evaluated (Jensen and Barr 1971;Visscher and Goddard 2015). Although there are hardly any heritability works on these chemical traits in holm oak, Tt heritability values were lower than those obtained in a previous study (Solla et al 2016).…”

Section: Heritability Of Constitutive Chemical Defencescontrasting

confidence: 61%

Interactive effects of biotic stressors and provenance on chemical defence induction by holm oak (Quercus ilex)

Rodríguez-Romero

Gallardo

Pérez

et al. 2021

Trees

View full text Add to dashboard Cite

Key Message The patterns of induced chemical defences in Quercus ilex leaves are specific to the biotic stress factor that causes them. Interactive effects between stressors depend on provenance. Abstract Quercus forests are suffering serious decline worldwide, closely linked to the consequences of climate change. The increase of biotic stressors threatens the survival of the holm oak (Quercus ilex), a dominant tree species in the Mediterranean Basin. A better understanding of its resistance mechanisms is urgently required to enable a better control of its decline. In this work, the ability of holm oaks from six Iberian provenances to respond to multiple biotic damage is studied through an analysis of their induced chemical defence patterns. Using 2016 seedlings established in a common garden trial (6 regions × 12 families/region × 7 seedlings/family × 4 treatments), biotic damage was induced at the root level (by infection with the widespread pathogen Phytophthora cinnamomi) and at the above-ground level (by mechanical defoliation). The levels of constitutive and induced total phenols, total tannins and condensed tannins were measured. Results showed that (1) the defensive chemical patterns present significant local and geographical variation, (2) survival to stress is more related to constitutive defences than induced ones, (3) the induced response is stressor-specific, and (4) there is an interactive effect amongst stressors whose sign (induction/inhibition) depends on the provenance. These findings on biotic stressor effects on the chemical defences and survival of holm oak can contribute to the development of genetic material selection programs in the integrated control of the widespread decline of Quercus.

show abstract

Section: Heritability Of Constitutive Chemical Defencescontrasting

confidence: 61%

Interactive effects of biotic stressors and provenance on chemical defence induction by holm oak (Quercus ilex)

Rodríguez-Romero

Gallardo

Pérez

et al. 2021

Trees

View full text Add to dashboard Cite

show abstract

“…For comparison of modeled trialing strategies, the W matrix was calculated by constructing a mean square (MS) for each source of random variation (elements of v ) based on the EMS for each field testing strategy (Tukey, 1956; Jensen and Barr, 1971; Bridges et al, 1991). This method is developed for a balanced design and assumes no covariance among the components of v .…”

Section: Methodsmentioning

confidence: 99%

Evaluating Testing Strategies for Plant Breeding Field Trials: Redesigning a CIMMYT International Wheat Nursery

et al. 2015

View full text Add to dashboard Cite

Genotypes produced from plant breeding programs for annual crops are evaluated in multiyear, multilocation field trials where a large number of genotypes grown in a few locations in the first year are progressively reduced by selection and tested in a greater number of locations in successive years. Provided fixed resources are specified, the efficiencies of testing strategies differing in the number of locations and replications used and in the number of genotypes tested in successive years can be evaluated by three statistics (genetic repeatability, acceptance probability, and potential gain) calculated from five variance components applicable to the field trials. The five variance components required are deployed genetic variance, genotype‐by‐year, genotype‐by‐location, and genotype‐by‐year‐by‐location interaction variances and the residual (error) variance. Strictly, known variance components are required, but the statistics and their standard errors can be calculated using robust estimates of the variance components obtained from a combined analysis over years of a large set of historical data from field trials that are connected by shared genotypes across years, as genotype‐by‐year and genotype‐by‐year‐by‐location variance components are estimable. Single‐year analyses are unsuitable, as no estimate of the interactions with year are available, and such analyses produce biased estimates of genetic variance and genotype‐by‐location interaction variance. These procedures are illustrated using an example from the CIMMYT international wheat breeding program to evaluate 2‐yr testing strategies for CIMMYT's Elite Spring Wheat Yield Trials that has been distributed and evaluated internationally since 1979.

show abstract

“…Negative estimates of variance components were set to zero in estimating σ P 2 . Standard errors of heritability estimates were approximated according to JENSEN and BARR (1971).…”

Section: Genetic Parametersmentioning

confidence: 99%

Early Selection of Radiata Pine

2006

View full text Add to dashboard Cite

Additive genetic, dominance genetic and phenotypic variances and corresponding correlations were estimated for growth data collected from disconnected half-diallel progeny trials involving 25 Pinus radiata D. DON parents and replicated across two sites in central North Island, New Zealand. Sectional area of stem was measured at three, seven, 10 and 13 years after planting at both sites, and height at three and 10 years at one site. Sectional area at three years exhibited similar levels of estimated additive (σA2) and dominance (σD2) genetic variance. However, levels of σD2 remained approximately constant between three and 13 years while σA2 increased substantially. Thus, sectional-area growth changed from being under equal additive and dominance genetic control at three years to almost complete additive genetic control from seven to 13 years. The greater increase in additive variance relative to phenotypic variance led to increases in individual heritability from 0.16 to 0.28 to 0.35 for sectional-area increments between 3-7, 7-10 and 10-13 years, respectively. Height growth exhibited negligible levels of σD2 for the three- and 10-year measurements. The early sectional-area increment between 3-7 years showed an estimated additive genetic correlation of 0.87 with “mature” sectional area at 13 years. Subsequent sectional-area increments between 7-10 and 10-13 years showed estimates of additive genetic correlations of 0.99 with sectional area at 13 years. Dominance genetic correlations were much lower in magnitude, reflecting inconsistent dominance effects over time.

show abstract

Standard Errors of Heritability Estimates Calculated from Variance Component Analysis af a Two-Way Classification

Cited by 9 publications

References 0 publications

Interactive effects of biotic stressors and provenance on chemical defence induction by holm oak (Quercus ilex)

Interactive effects of biotic stressors and provenance on chemical defence induction by holm oak (Quercus ilex)

Evaluating Testing Strategies for Plant Breeding Field Trials: Redesigning a CIMMYT International Wheat Nursery

Early Selection of Radiata Pine

Contact Info

Product

Resources

About