Breeding for improved growth and juvenile corewood stiffness in slash pine

2007 ◽  
Vol 37 (10) ◽  
pp. 1886-1893 ◽  
Author(s):  
Xiaobo Li ◽  
Dudley A. Huber ◽  
Gregory L. Powell ◽  
Timothy L. White ◽  
Gary F. Peter

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.

2003 ◽  
Vol 33 (6) ◽  
pp. 1102-1109 ◽  
Author(s):  
Anita C Koehn ◽  
James H Roberds ◽  
Robert L Doudrick

Photochemical quenching, nonphotochemical quenching, and yield of photosystem II were measured on seedlings of full-sibling, open-, and self-pollinated slash pine (Pinus elliottii Engelm. var. elliottii) families. Our results reveal that genetic variation in photochemical quenching and yield of photosystem II exists within this species. The pattern of variation found in these traits is consistent with the variance profile expected to occur as a result of segregation among nuclear genes. Variation among families accounted for 17% of the total variation observed in photochemical quenching, whereas the component for trees within families made up slightly more than 25% of the total. Less variation, both among families as well as among trees within families, was found for yield of photosystem II. A strikingly different pattern was observed for nonphotochemical quenching. Other than the error term, only pretreatment effects contributed significantly to the variation observed. This suggests that nonphotochemical quenching is largely influenced by environmental factors. With regard to associations between fluorescence and growth traits, both height and diameter growth were found to be positively correlated with photochemical quenching (0.36 and 0.33, respectively) when selfed and open-pollinated families were analyzed along with control-pollinated families.


Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 779 ◽  
Author(s):  
Hannah E. Willson ◽  
Hinayah Rojas de Oliveira ◽  
Allan P. Schinckel ◽  
Daniela Grossi ◽  
Luiz F. Brito

More recently, swine breeding programs have aimed to include pork quality and novel carcass (e.g., specific primal cuts such as the Boston butt or belly that are not commonly used in selection indexes) and belly traits together with growth, feed efficiency and carcass leanness in the selection indexes of terminal-sire lines, in order to efficiently produce pork with improved quality at a low cost to consumers. In this context, the success of genetic selection for such traits relies on accurate estimates of heritabilities and genetic correlations between traits. The objective of this study was to estimate genetic parameters for 39 traits in Duroc pigs (three growth, eight conventional carcass (commonly measured production traits; e.g., backfat depth), 10 pork quality and 18 novel carcass traits). Phenotypic measurements were collected on 2583 purebred Duroc gilts, and the variance components were estimated using both univariate and bivariate models and REML procedures. Moderate to high heritability estimates were found for most traits, while genetic correlations tended to be low to moderate overall. Moderate to high genetic correlations were found between growth, primal-cuts and novel carcass traits, while low to moderate correlations were found between pork quality and growth and carcass traits. Some genetic antagonisms were observed, but they are of low to moderate magnitude. This indicates that genetic progress can be achieved for all traits when using an adequate selection index.


1989 ◽  
Vol 13 (1) ◽  
pp. 51-56 ◽  
Author(s):  
G. R. Hodge ◽  
T. L. White ◽  
G. L. Powell ◽  
S. M. De Souza

Abstract Gains over unimproved seed for progeny from first generation--un-rogued, first generation--rogued, and one and one-half generation orchards of slash pine (Pinus elliottii var. elliottii) for individual tree volume at 15 years are predicted to be 10%, 15%, and 19%, respectively. Rustinfection of orchard progeny on sites where unimproved material incurs 50% infection are predicted to be 49%, 41%, and 35% for the three orchard types. Using a growth and yield model that incorporates fusiform rust, gains in individual tree volume and increased rust resistance were combinedto estimate effects on per acre yields. Percent volume per acre gains are predicted to be 7.0%, 13.2%, and 18.0% for the three orchard types. Collection and deployment of the most rust resistant seed to high rust hazard sites raises the gain on these sites and becomes increasingly beneficialas the rust hazard increases. South. J. Appl. For. 13(1): 51-56.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 42-42
Author(s):  
Breno Fragomeni ◽  
Zulma Vitezica ◽  
Justine Liu ◽  
Yijian Huang ◽  
Kent Gray ◽  
...  

Abstract The objective of this study was to implement a multi-trait genomic evaluation for maternal and growth traits in a swine population. Phenotypes for preweaning mortality, litter size, weaning weight, and average daily gain were available for 282K Large White pigs. The pedigree included 314k individuals, of which 35,731 were genotyped for 45K SNPs. Variance components were estimated in a multi-trait animal model without genomic information by AIREMLF90. Genomic breeding values were estimated using the genomic information by single-step GBLUP. The algorithm for proven and young (APY) was used to reduce computing time. Genetic correlation between proportion and the total number of preweaning deaths was 0.95. A strong, positive genetic correlation was also observed between weaning weight and average daily gain (r = 0.94). Conversely, the genetic correlations between mortality and growth traits were negative, with an average of -0.7. To avoid computations by expensive threshold models, preweaning mortality was transformed from a binary trait to two linear dam traits: proportion and a total number of piglets dead before weaning. Because of the high genetic correlations within groups of traits, inclusion of only one growth and one mortality trait in the model decreases computing time and allows for the inclusion of other traits. Reduction in computing time for the evaluation using APY was up to 20x, and no differences in EPD ranking were observed. The algorithm for proven and young improves the efficiency of genomic evaluation in swine without harming the quality of predictions. For this population, a binary trait of mortality can be replaced by a linear trait of the dam, resulting in a similar ranking for the selection candidates.


2006 ◽  
Vol 36 (4) ◽  
pp. 961-971 ◽  
Author(s):  
Veronica I Emhart ◽  
Timothy A Martin ◽  
Timothy L White ◽  
Dudley A Huber

We quantified basal area increment phenology over a 2-year period in one loblolly pine (Pinus taeda L.) and four slash pine (Pinus elliottii Engelm. var. elliottii) full-sib families propagated as rooting cuttings. In 2002, basal area growth started in March and stopped in October for both species, while in 2003, initiation and cessation occurred 2 weeks earlier for all families. In both years, peaks in basal area increment occurred in short (2–3 week) periods in the early spring for all families, followed by linear basal area growth until cessation. While there were significant size differences among taxa (species and families) at age 6 and 7 years, genetic differences in basal area growth rate were only expressed during short, discrete time periods primarily in the spring and fall. Basal area growth rate increased during periods when water soil availability increased (up to 300 mm), but an excess in water availability in the soil had a negative impact on growth. Within-family individual-tree broad-sense heritabilities ranged from 0.01 to 0.37 for all traits. In general, heritabilities were higher for growth traits than for phenological traits for all families. Both the strength and direction of correlation estimates of phenological traits with growth rate varied across families and years.


2000 ◽  
Vol 24 (2) ◽  
pp. 98-105 ◽  
Author(s):  
John Frampton ◽  
Bailian Li ◽  
Barry Goldfarb

Abstract Early growth and fusiform rust resistance of loblolly pine (Pinus taeda L.) rooted cuttings and seedlings from the same nine full-sib families established on two sites (Nassau Co., FL and Monroe Co., AL) were compared. Although site effects on growth were large, height, diameter and volume growth of the rooted cuttings and seedlings did not differ through the first six growing seasons in the field (with the exception of first year height growth at the Florida site). Fusiform rust (caused by Cronartium quercuum [Berk.] Miyabe ex Shirai f. sp. fusiforme [Cumm.] Burds. et Snow) incidence at age 6 yr was significantly lower in the rooted cuttings than the seedlings at both the Florida site (15.6 versus 22.3 %, respectively) and the Alabama site (46. 0 versus 51.0%, respectively). In addition, correlations of full-sib family performance between (1) rooted cuttings and seedlings and (2) rooted cuttings and seedling progeny test data were positive, statistically significant and moderate to high for both growth traits and fusiform rust incidence. Thus, families or individual trees selected from seedling genetic tests in existing tree improvement programs should also perform well as rooted cuttings. These results and those from similar studies indicate that field performance of loblolly pine rooted cuttings derived from seedling hedges should not be a concern. Large-scale propagation using rooted cuttings will deliver predicted gains from the selection and deployment of elite full-sib families and clones. In addition, the use of rooted cutting planting stock may offer a further reduction in fusiform rust incidence. South. J. Appl. For. 24(2):98-105.


2004 ◽  
Vol 34 (12) ◽  
pp. 2587-2600 ◽  
Author(s):  
Rodrigo Vergara ◽  
Timothy L White ◽  
Dudley A Huber ◽  
Barry D Shiver ◽  
Donald L Rockwood

Realized gains from selection of the first-generation breeding population of slash pine (Pinus elliottii Engelm. var. elliottii) were estimated using data from 38 field trials planted in large rectangular plots in the southeastern United States. The trials consisted of material selected for volume growth and planted by the Cooperative Forest Genetics Research Program at the University of Florida (19 trials) and by the Plantation Management Research Cooperative at the University of Georgia (19 trials). All trials contained slash pine seedlots collected from unrogued or lightly rogued first-generation seed orchards. Analyses of variance detected, on average, moderate gains in rust resistance (I50 = 43.1%) and site index (4.3%) and important gains in individual tree volume (7.7%) and stand yield (10.2%). Silvicultural treatments and age by realized gains interactions were never significant, but significant interactions between seedlots and trials showed that realized gains are not consistent at all sites. Overall results were highly consistent with predicted breeding values for rust resistance, but lower than expected for volume. On average, realized gain in stand yield for first-generation material was approximately 10%, or an extra inside-bark volume of 25 m3·ha–1 (357 feet3·acre–1) at 25 years.


2018 ◽  
Vol 58 (7) ◽  
pp. 1201 ◽  
Author(s):  
Mário L. Santana Jr ◽  
Joanir P. Eler ◽  
Annaiza B. Bignardi ◽  
Arione A. Boligon ◽  
José B. S. Ferraz

In tropical production systems, beef cattle are raised in highly heterogeneous environments. Heterogeneity is, therefore, expected to exist in the (co)variance components for traits of economic interest in different production environments. The main objective of the present study was to estimate genetic correlations between growth traits and reproductive performance of beef females, depending on the environment. The present study was conducted in the tropical region of Brazil, applying a multiple-trait random regression animal model to field records of heifer pregnancy (HP), hip height, bodyweight at ~18 months of age (BW18) and postweaning weight gain (PWG) from 20 893 Nelore females. As evidence of genotype by environment interaction (G × E), heterogeneity of genetic variance across environments was observed mainly for HP, PWG and BW18. Moreover, the estimates of genetic correlation within these traits reached values lower than unity on the environmental gradient. The genetic correlation among growth traits tended to be stronger in favourable environments, a fact that should favour correlated responses under these conditions. In contrast, the genetic correlations between growth traits and HP tended to become weaker and even exhibited little evidence of antagonism in more favourable environments. On the basis of these findings, selection for higher growth in extreme favourable environments should result in little or no damage to HP as a correlated response. All these results lead us to believe that the G × E is an important factor to be considered in genetic evaluations of beef cattle raised in tropical environments.


2012 ◽  
Vol 61 (1-6) ◽  
pp. 186-198 ◽  
Author(s):  
T. Z. Ye ◽  
K. J. S. Jayawickrama

AbstractMeasurements on growth traits up to 41 years of age from 68 progeny sites in eight first-generation breeding zones of coastal Douglas-fir (Pseudotsuga menziesii [MIRB.] FRANCO var. menziesii) in the US Pacific Northwest were used to investigate age trends of genetic parameters and to determine optimum age of selection. Heritabilities and age-age genetic correlations were estimated using univariate or bivariate mixed model analyses. Heritability estimates tended to increase with age for both total growth and growth increment traits. The estimates showed different age trends among breeding zones, but the differences were generally small. Age-age genetic correlations for total growth traits fitted Lambeth’s model surprisingly well, despite the data being collected from multiple breeding zones. Using rotation-age (i.e., 50yr) volume as the selection criterion, the greatest correlated gains per year were achieved by making family selection at juvenile ages (i.e., 9 for height, 13 for diameter, and 11 for volume). Similar results were obtained for within-family selection except that the optimum ages of selection were 2~4 years later than that from family selection, i.e., 11 for height, 15 for diameter and volume. Early selection on total height was always more efficient and had earlier optimum ages than on other growth traits. The optimum ages of early family selection on total growth were 4~11 years earlier than on the corresponding growth increment traits. It was also evident that the optimum ages of selection occurred later for slow-growth trials than for fast-growing trials.


2008 ◽  
Vol 57 (1-6) ◽  
pp. 306-311 ◽  
Author(s):  
B. Hannrup ◽  
G. Jansson ◽  
Ö. Danell

Abstract To estimate the amount of genotype by environment interaction (G x E) data was obtained within the Swedish breeding program of Pinus sylvestris L. The calculations were based on estimates of G x E expressed by the genetic correlations across trials. In total, 66 progeny trials were included coming from 17 different test series. The number of parents tested per progeny trial was in average 52. Some parents were tested in several series and in total 812 parents were represented in the study. The results of our study showed that the amount of G x E for growth traits in Pinus sylvestris in southern Sweden was low. The median genetic correlation across trials for height, height increment and diameter were in the range 0.75-0.80 and the pattern of interaction was largely unpredictable from site differences in site index, latitude, longitude and altitude.


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