Breeding strategies for Larixoccidentalis: adaptations to the biotic and abiotic environment in relation to improving growth

Two disparate studies detected additive genetic variances and covariances for traits reflecting growth, growth rhythm, and disease resistance in Larixoccidentalis Nutt. after 4 and 8 years of field testing. Heritabilities of moderate size combined with large phenotypic variances to presage relatively large responses to direct selection: genetic gains in growth of about 9% seemed readily feasible per unit of selection intensity. Strong genetic correlations (absolute value is greater than 0.6) linked growth traits with several traits that reflect growth rhythm and with defoliation from Meria needle cast (Merialaricis Vuill.). The results suggest that selecting for increased growth also increases resistance to needle cast but disrupts the growth rhythm typical of natural populations. Selecting for the rate of shoot elongation, however, should increase resistance to the needle cast, prevent the deterioration of growth rhythm, and still provide 70% of the gains in growth that would be available from direct univariate selection.

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Genetic Control of Growth Traits in Shortleaf Pine in Missouri

Southern Journal of Applied Forestry ◽

10.1093/sjaf/29.4.200 ◽

2005 ◽

Vol 29 (4) ◽

pp. 200-204 ◽

Cited By ~ 2

Author(s):

David P. Gwaze ◽

Ross Melick ◽

Charly Studyvin ◽

Mark Coggeshall

Keyword(s):

Growth Traits ◽

Genetic Correlations ◽

Selection Criterion ◽

Seed Orchard ◽

Direct Selection ◽

Pinus Echinata ◽

Shortleaf Pine ◽

Individual Tree ◽

High Heritability ◽

Heritability Estimates

Abstract Genetic parameters for height (HT), diameter (diameter at breast height [dbh]), and volume for a shortleaf pine (Pinus echinata Mill.) population in Missouri were estimated from a single progeny test comprising 44 half-sibling families assessed at 3, 5, 7, 10, and 17 years. Individual tree heritability estimates for growth traits at age 10 years and younger were high (0.30–0.43), and those at age 17 years were low (0.11–0.24). Heritability estimates for dbh were lower than those for HT. Family mean heritability estimates were moderate to high (0.32–0.66). Genetic correlations were higher than their phenotypic counterparts for all growth traits. Age-age genetic correlations for growth traits were moderate to high (0.68–0.98), indicating opportunity for early selection. Genetic correlations between different growth traits were high (0.81–1.00). Indirect selection on age 5- or 7-year HTs may be expected to produce over 25% more volume at 17 years compared with direct selection for volume at age 17 years. Efficiencies of selection suggest that early HT is a better selection criterion for volume at older ages than dbh because of the high heritability at young ages and strong juvenile-mature genetic correlations. Genetic gain in an unrogued seed orchard was predicted to be 6.7 and 27.2% for 10- and 17-year volume, respectively. These results suggest that growth traits in shortleaf pine in Missouri have high genetic variation, and genetic improvement was effective. South. J. Appl. For. 29(4):200–204.

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Selection for cow lifetime pregnancy rate using bull and heifer growth and reproductive traits in composite cattle

Canadian Journal of Animal Science ◽

10.4141/a99-135 ◽

2000 ◽

Vol 80 (3) ◽

pp. 507-510 ◽

Cited By ~ 7

Author(s):

P. B. Mwansa ◽

R. A. Kemp ◽

D. H. Crews Jr ◽

J. P. Kastelic ◽

D. R. C. Bailey ◽

...

Keyword(s):

Birth Weight ◽

Key Words ◽

Pregnancy Rate ◽

Growth Traits ◽

Genetic Correlations ◽

Reproductive Traits ◽

Genetic Change ◽

Direct Selection ◽

Scrotal Circumference ◽

Selection For

Genetic correlations of lifetime pregnancy rate with bull and heifer growth and reproductive traits in a beef composite population were estimated. Yearling scrotal circumference had an unfavorable genetic correlation (rg = −0.25) while yearling tonometer score was favorably related (rg = 0.22) to lifetime pregnancy rate. Heifer pregnancy rate, birth weight, weaning weight, yearling weight and age at puberty in heifers had significant genetic correlations (rg = 0.97, 0.58, 0.57, 0.33 and −0.21, respectively) with lifetime pregnancy rate. Lifetime pregnancy rate may be successfully predicted by easy-to-measure heifer growth traits. Using indices including scrotal and heifer growth traits, annual genetic change in lifetime pregnancy rate may be increased 3.1 times compared with direct selection. Key words: Scrotal circumference, tonometer, pregnancy, reproduction, puberty

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Diallel Crossing in Pinus cembra: V. Age Trends in Genetic Parameters and Genetic Gain for Height

Silvae Genetica ◽

10.1515/sg-2012-0009 ◽

2012 ◽

Vol 61 (1-6) ◽

pp. 66-79

Author(s):

I. Blada ◽

F. Popescu

Keyword(s):

Genetic Gain ◽

Growth Traits ◽

Block Design ◽

Genetic Correlations ◽

Field Testing ◽

Phenotypic Variance ◽

Total Height ◽

Testing Period ◽

Randomized Block Design ◽

Diallel Mating Design

AbstractA full diallel mating design (10 parents) was carried out in a Swiss stone pine panmictic population from the Carpathian Mountains. At age six, after nursery testing, the progenies were field planted to one site, using a completely randomized block design with 100 families, four replicates and a 15 tree row-plot per replication, spaced 2.5 × 2.5 m. Total and annual height of all individuals of this test was assessed at successive ages, between ages eight and 16. In addition, weight of 100 seeds and cotyledon number were considered in correlation analyses. Significant differences occurred in total height for general and specific combining ability effects. Variance components, heritabilities, genetic correlations and genetic gains on growth traits and survival at age 16 were estimated. Across the field testing period, GCA3)variance increased with time, accounting for 65% of plot mean phenotypic variance by age 16. In contrast, SCA variance declined as the progeny test aged accounting for only 9% by age 16. The time trend of the four heritability estimates for total height increased with age across the testing period reaching their highest level between age 14 and 16. Genetic correlations over time for total height rose from 0.85 at age two to 0.94 at age six and then leveled off across the field test indicating that if the goal is to improve 16-year height, early selection can be considered at age six. By selecting the best 10%, 15% and 20% of individuals within the best fullsib families, a genetic gain in total height of 12.4 %, 11.0% and 9.9% respectively, could be achieved at age 16. A higher gain can be obtained if the best general combiner parents are selected and intermated.

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Genetic parameters by Bayesian inference for dual purpose Jaffarabadi buffaloes

Archives Animal Breeding ◽

10.5194/aab-55-567-2012 ◽

2012 ◽

Vol 55 (6) ◽

pp. 567-576 ◽

Cited By ~ 2

Author(s):

C. H. Mendes Malhado ◽

A. C. Mendes Malhado ◽

A. Amorim Ramos ◽

P. L. Souza Carneiro ◽

F. Siewerdt ◽

...

Keyword(s):

Bayesian Inference ◽

Milk Yield ◽

Genetic Parameters ◽

Growth Traits ◽

Average Daily Gain ◽

Genetic Correlations ◽

Direct Selection ◽

Dual Purpose ◽

Lactation Length ◽

Selection For

Abstract. Knowledge of genetic parameters is essential for improved reproductive management and increased yield. Quantitative analysis of genetic parameters is lacking for many breeds of buffaloes. This article provides the first estimate of genetic parameters for dual purpose (meat and milk) Brazilian Jaffarabadi buffaloes, using Bayesian inference. Data on milk yield (MY), lactation length (LL), weight at 205 days (W205) and 365 (W365) days of age, and average daily gain (ADG) from 205 to 365 days of age were collected in two herds. Bivariate analyses (using the program MTGSAM) were performed with the Gibbs sampler to obtain estimates of variance and covariance. Average lactation milk yield and lactation length were 1620.2±450.9 kg and 257.6±46.8 days, respectively, and the mean values for weight traits (kg) were 181.6±63.3 (W205), 298.04±116.1 (W365), and 0.73±0.35 (ADG). Heritability estimates (modes) were 0.16 for MY, 0.10 for LL, 0.43 for W205, 0.48 for W365 and 0.32 for ADG. There was a high genetic correlation (0.96) between milk yield and lactation length and very high genetic correlations (0.99) between the three growth traits. Our data suggest that both milk production and growth traits have clear potential for yield improvement through direct selection in this dual purpose breed. The selection for weight at an early age would be successful and selection for MY can be performed in the first lactation.

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Genetic Variation in an International Provenance-Progeny Test of Pinus caribaea Mor. var. bahamensis Bar. et Gol., in São Paulo, Brazil

Silvae Genetica ◽

10.1515/sg-2008-0028 ◽

2008 ◽

Vol 57 (1-6) ◽

pp. 181-187 ◽

Cited By ~ 2

Author(s):

A. M. Sebbenn ◽

F. C. Arantes ◽

O. V. Boas ◽

M. L. M. Freitas

Keyword(s):

Growth Traits ◽

Genetic Correlations ◽

Sao Paulo ◽

Progeny Test ◽

Direct Selection ◽

São Paulo ◽

Pinus Caribaea ◽

Andros Island ◽

Selection For ◽

Analysis Of Variation

Abstract A combined provenance-progeny test of Pinus caribaea var. bahamensis was established in Paraguaçu Paulista Experimental Station, São Paulo State, Brazil, in a “compact family” blocks design with 14 provenances, 2 to 10 families per provenance, 5 individuals per subplot, and 7 replications. Variation among and within island, provenances and families and genetic parameters for d.b.h., height, and real volume were investigated, about 15 years after planting. Analysis of variation for all studied traits revealed significant differences among islands, provenances within island and families within islands, suggesting the possibility of increasing the timber yield through selection of the more productive provenances and families within the best island. Genetic correlations on growth traits were high and statistically significant, indicating that substantial gains could be made through indirect selection for one trait based on direct selection for another. Norman Castle provenance from Abaco Island performed best for d.b.h. height and volume, while San Andros and Little Harbour Cay, both from Andros Island performed worst for d.b.h. and height, respectively, and South Riding from Grand Bahamas Island performed worst for volume. The best provenance growth compared to that P. elliottii var. elliottii species at the same experimental site suggests that P. caribaea var. bahamensis has high silvicultural potential for the Paraguaçu Paulista region.

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HERITABILITIES OF AND GENETIC CORRELATIONS BETWEEN SOME GROWTH TRAITS IN NIGERIAN LOCAL CHICKENS

Nigerian Journal of Animal Production ◽

10.51791/njap.v21i1.1078 ◽

2021 ◽

Vol 21 ◽

pp. 19-24

Author(s):

A. L. Ebangi ◽

S. N. Ibe

Keyword(s):

Body Weight ◽

Growth Traits ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

Appreciable Amount ◽

Direct Selection ◽

Chicken Population ◽

Pleiotropic Action ◽

Average Body ◽

Local Chickens

Heritabilities of and genetic correlations between body weight, shank length, keel length and breast width in a population of Nigerian local chickens at 6 weeks of age were estimatedusing a total of 170 chicks of both sexes obtained from 5 sires each mated to 4 dams by artifical insemination in a nested fashion. Average body weight, shank length, keel length and breast width at this age were 114.97g, 3.48cm, 3.35cm and 3.22cm, respectively.Genetic correlations between the traits were positive and high, ranging from 0.99 to 1.51. The moderate to high heritabilities (hs2) of these growth traits at 6 weeks point to the existence of an appreciable amount of additive genetic variance in the local chicken population and indicate that improvement in these traits can be brought about by intrapopulation selection. The high genetic correlations indicate the pleiotropic action of genes controlling these traits and that, by direct selection for any one of them, genetic improvement in the others will be realized as correlated responses.

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Genetic parameters and efficiency of early selection for half rotation-aged growth and form traits in Pinus taeda in China

Silvae Genetica ◽

10.1515/sg-2013-0033 ◽

2013 ◽

Vol 62 (1-6) ◽

pp. 277-284 ◽

Cited By ~ 2

Author(s):

Huixiao Yang ◽

Tianyi Liu ◽

Chunxin Liu ◽

Jinbang Wang ◽

Kaer Chen ◽

...

Keyword(s):

Pinus Taeda ◽

Genetic Parameters ◽

Growth Traits ◽

Genetic Correlations ◽

Early Selection ◽

Direct Selection ◽

Individual Tree ◽

Stem Straightness ◽

Selection For ◽

Heritability Estimates

Abstract Genetic parameters for height (H), diameter at breast height (DBH), stem straightness (STR), and under crown clear bole height (CH) of loblolly pine (Pinus taeda L.) were estimated for 255 families (209 open pollinated (OP) and 46 controlled pollinated (CP) families) using a family model and an individual tree model at age 1, 2, 3, 5, 11, and 15 years. Heritability estimates for growth traits of individual trees at age 11 years were the highest (0.17-0.78), and those at age 15 years were the lowest (0.05-0.74). Heritability estimates for DBH, STR, and CH were lower than those for H. Genetic correlations between H and DBH were generally strongly positive, attained a maximum values at age 2 to 3, and declined slightly thereafter. The genetic correlations between CH at age 11 and both H and DBH at different ages were moderate. Age-age genetic correlations for growth traits were moderate to high (0.56-0.91) at age 5 for half-rotation age (15 years), indicating the opportunity exists for early selection. Indirect selection from the age 5 to 11 years for H and DBH could be expected to produce gains of over 50% and 35% respectively, for these two ages, relative to direct selection at age 15. Efficiencies of early selection for H and DBH indicated that growth at maturity could be improved by early selection.

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Non-Destructive Assessment of Wood Stiffness in Scots Pine (Pinus sylvestris L.) and its Use in Forest Tree Improvement

Forests ◽

10.3390/f10060491 ◽

2019 ◽

Vol 10 (6) ◽

pp. 491 ◽

Cited By ~ 7

Author(s):

Irena Fundova ◽

Tomas Funda ◽

Harry X. Wu

Keyword(s):

Scots Pine ◽

Growth Traits ◽

Wood Quality ◽

Genetic Correlations ◽

Forest Tree ◽

Wood Stiffness ◽

Standing Trees ◽

Genetic And Phenotypic Correlations ◽

Sib Families ◽

Using Data

Wood stiffness is an important wood mechanical property that predetermines the suitability of sawn timber for construction purposes. Negative genetic correlations between wood stiffness and growth traits have, however, been reported for many conifer species including Scots pine. It is, therefore, important that breeding programs consider wood stiffness and growth traits simultaneously. The study aims to (1) evaluate different approaches of calculating the dynamic modulus of elasticity (MOE, non-destructively assessed stiffness) using data from X-ray analysis (SilviScan) as a benchmark, (2) estimate genetic parameters, and (3) apply index selection. In total, we non-destructively measured 622 standing trees from 175 full-sib families for acoustic velocity (VEL) using Hitman and for wood density (DEN) using Resistograph and Pilodyn. We combined VEL with different wood densities, raw (DENRES) and adjusted (DENRES.TB) Resistograph density, Pilodyn density measured with (DENPIL) and without bark (DENPIL.B), constant of 1000 kg·m−3 (DENCONST), and SilviScan density (DENSILV), to calculate MOEs and compare them with the benchmark SilviScan MOE (MOESILV). We also derived Smith–Hazel indices for simultaneous improvement of stem diameter (DBH) and wood stiffness. The highest additive genetic and phenotypic correlations of the benchmark MOESILV with the alternative MOE measures (tested) were attained by MOEDENSILV (0.95 and 0.75, respectively) and were closely followed by MOEDENRES.TB (0.91 and 0.70, respectively) and MOEDENCONST and VEL (0.91 and 0.65, respectively for both). Correlations with MOEDENPIL, MOEDENPIL.B, and MOEDENRES were lower. Narrow-sense heritabilities were moderate, ranging from 0.39 (MOESILV) to 0.46 (MOEDENSILV). All indices revealed an opportunity for joint improvement of DBH and MOE. Conclusions: MOEDENRES.TB appears to be the most efficient approach for indirect selection for wood stiffness in Scots pine, although VEL alone and MOEDENCONST have provided very good results too. An index combining DBH and MOEDENRES.TB seems to offer the best compromise for simultaneous improvement of growth, fiber, and wood quality traits.

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Corrigendum to: Consequences of genetic selection for environmental impact traits on economically important traits in dairy cows

Animal Production Science ◽

10.1071/an16592_co ◽

2018 ◽

Vol 58 (10) ◽

pp. 1966

Author(s):

Purna Kandel ◽

Sylvie Vanderick ◽

Marie-Laure Vanrobays ◽

Hélène Soyeurt ◽

Nicolas Gengler

Keyword(s):

Dairy Cows ◽

Body Condition Score ◽

Genetic Correlations ◽

Genetic Selection ◽

Selection Response ◽

Direct Selection ◽

Correlated Response ◽

Production Traits ◽

Ch4 Emissions ◽

Natural Logarithm

Methane (CH4) emission is an important environmental trait in dairy cows. Breeding aiming to mitigate CH4 emissions require the estimation of genetic correlations with other economically important traits and the prediction of their selection response. In this study, test-day CH4 emissions were predicted from milk mid-infrared spectra of Holstein cows. Predicted CH4 emissions (PME) and log-transformed CH4 intensity (LMI) computed as the natural logarithm of PME divided by milk yield (MY). Genetic correlations of PME and LMI with traits used currently were approximated from correlations between estimated breeding values of sires. Values were for PME with MY 0.06, fat yield (FY) 0.09, protein yield (PY) 0.13, fertility 0.17; body condition score (BCS) –0.02; udder health (UDH) 0.22; and longevity 0.22. As expected by its definition, values were negative for LMI with production traits (MY –0.61; FY –0.15 and PY –0.40) and positive with fertility (0.36); BCS (0.20); UDH (0.08) and longevity (0.06). The genetic correlations of 33 type traits with PME ranged from –0.12 to 0.25 and for LMI ranged from –0.22 to 0.18. Without selecting PME and LMI (status quo) the relative genetic change through correlated responses of other traits were in PME by 2% and in LMI by –15%, but only due to the correlated response to MY. Results showed for PME that direct selection of this environmental trait would reduce milk carbon foot print but would also affect negatively fertility. Therefore, more profound changes in current indexes will be required than simply adding environmental traits as these traits also affect the expected progress of other traits.

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Breeding for improved growth and juvenile corewood stiffness in slash pine

Canadian Journal of Forest Research ◽

10.1139/x07-043 ◽

2007 ◽

Vol 37 (10) ◽

pp. 1886-1893 ◽

Cited By ~ 26

Author(s):

Xiaobo Li ◽

Dudley A. Huber ◽

Gregory L. Powell ◽

Timothy L. White ◽

Gary F. Peter

Keyword(s):

Genetic Correlation ◽

Growth Traits ◽

Low Cost ◽

Genetic Correlations ◽

Volume Growth ◽

Pinus Elliottii ◽

Tree Improvement ◽

Slash Pine ◽

Narrow Sense Heritability ◽

Improvement Programs

The importance of integrating measures of juvenile corewood mechanical properties, modulus of elasticity in particular, with growth and disease resistance in tree improvement programs has increased. We investigated the utility of in-tree velocity stiffness measurements to estimate the genetic control of corewood stiffness and to select for trees with superior growth and stiffness in a progeny trial of 139 families of slash pine, Pinus elliottii Engelm. grown on six sites. Narrow-sense heritability estimates across all six sites for in-tree acoustic velocity stiffness at 8 years (0.42) were higher than observed for height (0.36) and diameter at breast height (DBH) (0.28) at 5 years. The overall type B genetic correlation across sites for velocity stiffness was 0.68, comparable to those found for DBH and volume growth, indicating that family rankings were moderately repeatable across all sites for these traits. No significant genetic correlations were observed between velocity stiffness, DBH, and volume growth. In contrast, a significant, but small, favorable genetic correlation was found between height and velocity stiffness. Twenty percent of the families had positive breeding values for both velocity stiffness and growth. The low cost, high heritability and nearly independent segregation of the genes involved with in-tree velocity stiffness and growth traits indicate that acoustic methods can be integrated into tree improvement programs to breed for improved corewood stiffness along with growth in slash pine.

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