scholarly journals Maternal and carryover effects on early growth of Eucalyptus globulus

2003 ◽  
Vol 33 (11) ◽  
pp. 2108-2115 ◽  
Author(s):  
Gustavo A Lopez ◽  
Bradley M Potts ◽  
René E Vaillancourt ◽  
Luis A Apiolaza
Keyword(s):  
Genetic Variation ◽  
Eucalyptus Globulus ◽  
Genetic Parameters ◽  
Germination Rate ◽  
Seed Mass ◽  
Field Trials ◽  
Early Growth ◽  
Reciprocal Effects ◽  
Carryover Effects ◽  
Reciprocal Differences

Maternal and nonmaternal reciprocal effects were compared with nuclear genetic and carryover effects using a diallel mating amongst eight Eucalyptus globulus Labill. wild parents from northeastern and southern Tasmania races. Seed mass exhibited a significant maternal effect, increasing seed germinative capacity but not germination rate. After accounting for variation in seed mass, both germinative capacity and germination rate exhibited significant reciprocal effects, but these were non maternal in origin. Rapid germination and large seeds resulted in significantly larger seedlings in the nursery, but these carryover effects diminished with age. In contrast, the expression of genetic effects increased with age. Significant additive genetic variation was detected for growth by age 3 years and significant reciprocal differences were detected at the race level after 2 years in field trials. If common, such reciprocal effects could bias genetic parameters and impact on the choice of cross-direction in deployment programs. Failure to account for carryover effects in genetic analyses may inflate estimates of genetic variation for growth during early stages of the life cycle.

Genetic control of Eucalyptus globulus harvest traits

2015 ◽  
Vol 45 (6) ◽  
pp. 615-624 ◽  
Author(s):  
Matthew G. Hamilton ◽  
Mauricio Acuna ◽  
John C. Wiedemann ◽  
Rick Mitchell ◽  
David J. Pilbeam ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Eucalyptus Globulus ◽  
Genetic Correlations ◽  
Basal Area ◽  
Field Trials ◽  
Slight Reduction ◽  
Growth And Survival ◽  
Short Rotation ◽  
Stem Straightness ◽  
Tree Genetics

The cost of harvesting short-rotation plantation eucalypts can be in excess of AU$2500·ha−1. Despite this high cost, the extent to which harvesting productivity is affected by tree genetics is not well understood. We address this issue in a study of two 10-year-old genetic field trials of Eucalyptus globulus Labill. in Australia. Standing-tree traits analysed were survival, diameter at breast height, basal area, and stem straightness and forking. Harvest traits analysed were volume, time, and productivity. Genetic group and within-group genetic variation (additive and dominance), stand-level family variation, phenotypic and genetic correlations, and the effects of inbreeding were estimated for these traits. The different scenarios studied showed that plantation harvest productivity was affected by tree genetics to some degree but was mainly affected through positive covariation with stem diameter. Harvest productivity is thus unlikely to have been adversely affected by past selection. Although no significant additive or dominance genetic variation in stem forking or straightness was detected, weak phenotypic correlations were consistent with harvest productivity being higher in straighter trees with no forking. High inbreeding depression was evident for growth and survival; however, in open-pollinated progeny, this resulted in only a slight reduction in harvest productivity (5.5%) compared with out-crossed progeny.

Geographic Patterns of Genetic Variation in Eucalyptus globulus ssp. globulus and a Revised Racial Classification

1999 ◽  
Vol 47 (2) ◽  
pp. 237 ◽  
Author(s):  
G. W. Dutkowski ◽  
B. M. Potts
Keyword(s):  
Genetic Variation ◽  
Eucalyptus Globulus ◽  
Multivariate Analyses ◽  
Basic Density ◽  
Field Trials ◽  
Racial Classification ◽  
Regional Patterns ◽  
Growth And Survival ◽  
Geographic Patterns ◽  
Quantitative Genetic

The geographic patterns of genetic variation in a wide variety of quantitative traits were studied in Eucalyptus globulus ssp. globulus and its intergrades, leading to a revised racial classification. The analysis was based on 35 traits assessed in five field trials in northern Tasmania from approximately 500 open-pollinated families, encompassing 49 collection localities in native stands. There were significant differences between the collection localities for most traits. While growth and survival traits exhibited weak spatial structuring, there were clear regional patterns in bark thickness, wood basic density, flowering precocity and some aspects of juvenile leaf morphology. There were a number of significant correlations between trait locality means, but few simple correlations between the regional patterns observed and climate. Multivariate analyses indicated that the localities could be effectively amalgamated into larger, geographically concordant races. A hierarchy of five major groupings of 13 races and 20 subraces is proposed to account for most of the quantitative genetic variation while allowing for outliers and intermediate populations. Some areas of the distribution may need further sampling to more accurately elucidate their racial affinities, especially those with traits of high economic importance.

Variation in the morphology and flowering time of cluster clover (Trifolium glomeratum L.) and its relationship to distribution in southern Australia

1995 ◽  
Vol 46 (5) ◽  
pp. 1027 ◽  
Author(s):  
FP Smith ◽  
PS Cocks ◽  
MA Ewing
Keyword(s):  
Genetic Variation ◽  
Flowering Time ◽  
Seed Mass ◽  
Annual Rainfall ◽  
Strongly Correlated ◽  
Summer Maximum ◽  
Maximum Temperatures ◽  
Pattern Of Variation ◽  
Growth Habits

Cluster clover is a widely distributed and ecologically successful introduced legume in southern Australia. In an attempt to understand the role of genetic variation in this success, morphological and physiological traits were measured in 94 accessions from southern Australia and 6 from the Mediterranean basin. Flowering time ranged from 105 to 185 days after sowing, but was not strongly correlated with annual rainfall or length of growing season at the site of collection. Variation in other traits partitioned the populations into two morphs which, apart from flowering time and leaf marker, were largely homogeneous. The morphs differed significantly in floret number per inflorescence (22 v. 32-37) and seed mass (379 8g v. 523 8g), had different growth habits and strong within-morph associations between leaf markers and stipule and petal coloration. The morphs differed in their distributions within southern Australia and the pattern of distribution was related to summer maximum temperatures, winter minimum temperatures and spring rainfall. These results demonstrate that genetic variation has been important to the success of cluster clover and suggests that the variation is organized. The pattern of variation observed and its relationship to ecogeography is consistent with findings for other highly inbreeding species. A map of the species distribution in Western Australia is presented.

Genetic Parameters and Genotype-by-Environment Interactions in Regional Progeny Tests of Pinus taeda L. in the Southern USA

2020 ◽  
Author(s):  
Edwin Lauer ◽  
Andrew Sims ◽  
Steven McKeand ◽  
Fikret Isik
Keyword(s):  
Genetic Variation ◽  
Pinus Taeda ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Breeding Program ◽  
Model Fit ◽  
Genotype By Environment Interactions ◽  
Genotype By Environment ◽  
Progeny Tests ◽  
Pinus Taeda L

Abstract Genetic parameters were estimated using a five-series multienvironment trial of Pinus taeda L. in the southern USA. There were 324 half-sib families planted in five test series across 37 locations. A set of six variance/covariance matrices for the genotype-by-environment (G × E) effect for tree height and diameter were compared on the basis of model fit. In single-series analysis, extended factor analytical models provided generally superior model fit to simpler models for both traits; however, in the combined-series analysis, diameter was optimally modeled using simpler variance/covariance structures. A three-way compound term for modeling G × E interactions among and within series yielded substantial improvements in terms of model fit and standard errors of predictions. Heritability of family means ranged between 0.63 and 0.90 for both height and diameter. Average additive genetic correlations among sites were 0.70 and 0.61 for height and diameter, respectively, suggesting the presence of some G × E interaction. Pairs of sites with the lowest additive genetic correlations were located at opposite ends of the latitude range. Latent factor regression revealed a small number of parents with large factor scores that changed ranks significantly between southern and northern environments. Study Implications Multienvironmental progeny tests of loblolly pine (Pinus taeda L.) were established over 10 years in the southern United States to understand the genetic variation for the traits of economic importance. There was substantial genetic variation between open-pollinated families, suggesting that family selection would be efficient in the breeding program. Genotype-by-environment interactions were negligible among sites in the deployment region but became larger between sites at the extremes of the distribution. The data from these trials are invaluable in informing the breeding program about the genetic merit of selection candidates and their potential interaction with the environment. These results can be used to guide deployment decisions in the southern USA, helping landowners match germplasm with geography to achieve optimal financial returns and conservation outcomes.

scholarly journals Selection of cotton lines for high oil content

2017 ◽  
Vol 52 (7) ◽  
pp. 530-538 ◽  
Author(s):  
Luiz Paulo de Carvalho ◽  
Josiane Isabela da Silva Rodrigues ◽  
Francisco José Correia Farias
Keyword(s):  
Oil Content ◽  
Genetic Parameters ◽  
Fiber Quality ◽  
Rio Grande ◽  
Field Trials ◽  
The State ◽  
The Other ◽  
Expected Gain ◽  
High Heritability ◽  
Selection Of

Abstract: The objective of this work was to evaluate the oil content and characters related to fiber quality and yield in cotton lines (Gossypium hirsutum), in order to select genotypes with high oil content and acceptable levels of the other characters. Twenty-two F6 lines and three checks were cultivated in three field trials - two in the municipality of Apodi, in the state of Rio Grande do Norte, and one in the municipality of Barbalha, in the state of Ceará, both in Brazil. The genetic parameters and the genetic gain from selecting 20% of the lines were estimated according to their means in each environment and in the group of environments. Regarding oil content, there is genetic variability, and the selection based on the overall mean is indicated, since this character showed high heritability, with 4.58% expected gain. The lines selected with this criterion have oil contents between 23.52 and 24.51%, which are higher than those of the Brazilian cultivar BRS Aroeira with the highest grain oil content (22.04%).

MATERNAL AND RECIPROCAL EFFECTS ON SEEDLING CHARACTERS IN ARABIDOPSIS THALIANA (L.) HEYNH

Genetics ◽  
1976 ◽  
Vol 82 (4) ◽  
pp. 677-683
Author(s):  
L A Corey ◽  
D F Matzinger ◽  
C Clark Cockerham
Keyword(s):  
Arabidopsis Thaliana ◽  
Root Length ◽  
Early Growth ◽  
F1 Hybrids ◽  
Reciprocal Effects ◽  
Plant Weight ◽  
Weight Percentage ◽  
Maternal Genotype ◽  
Seedling Characters ◽  
Growth Characters

ABSTRACT Five early growth characters were examined in six races of Arabidopsis thaliana (L.) Heynh, their reciprocal F1 hybrids (1974) and F1 by tester hybrids, using a seventh race as a paternal tester. Three of the five characters were also examined at two nutrient levels in reciprocal F1 hybrids (1972) of all seven races. Analyses of F1 and F1 by tester hybrids revealed significant maternal effects in all characters examined in F1 hybrids (1972) and in root length and plant weight of F1 (1974) and F1 by tester hybrids. Significant reciprocal effects were found for plant weight in F1 by tester hybrids and for seed weight, percentage of germination and root length in F1 (1974) and F1 by tester hybrids. The presence of significant maternal and/or reciprocal components in both F1 (1974) and F1 by tester diallels suggests that differences in maternal cytoplasm rather than maternal genotype per se were responsible for much of the variation resulting from these non-direct genetic effects.

scholarly journals Adaptability, stability, productivity and genetic parameters in slash pine second-generation families in early age

2016 ◽  
Vol 65 (1) ◽  
pp. 71-82 ◽  
Author(s):  
M.K. Pagliarini ◽  
W.S. Kieras ◽  
J.P. Moreira ◽  
V.A. Sousa ◽  
J.Y. Shimizu ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Genetic Parameters ◽  
Second Generation ◽  
Growth Traits ◽  
Environmental Influence ◽  
Block Design ◽  
Slash Pine ◽  
Phenotypic Traits ◽  
Early Age ◽  
Wood Volume

AbstractThe study was conducted to estimate the stability, adaptability, productivity and genetic parameters in Slash pine second-generation half-sib families, considering phenotypic traits in early age. Forty-four families from a first generation seed orchard in Colombo-PR, Brazil, were used in this study. Two progenies tests were established in a randomized complete block design. The first test was implemented in March 2009 in Ribeirão Branco, São Paulo state, containing 40 blocks, one tree per plot, 44 treatments (progenies) and 6 controls. Another test was implemented in Ponta Grossa, Paraná state, using the same experimental design and number of plants per plot, and with 24 treatments, 32 blocks. The growth traits evaluated were total height, diameter at breast height (dbh) and wood volume, within five years. The form traits evaluated were stem form, branch thickness, branch angle, number of branches, fork and fox tail five years after planting. Deviance analysis and estimates of stability, adaptability, productivity and genetic parameters were performed using the methods of best linear unbiased predictor (BLUP) and residual maximum likelihood (REML). There was significant variation among progenies for growth and form traits. Considerable genetic variation was detected mainly for wood volume. High coefficients of genetic variation and heritability showed low environmental influence on phenotypic variation, which is important for the prediction of genetic gain by selection. Crosses between different progenies individuals groups will be prioritized for obtaining heterotics genotypes and increase the probability of obtaining high specific combining ability.

scholarly journals The effects of ploidy and seed mass on the emergence and early vigour of perennial ryegrass (Lolium perenne L.) cultivars

2003 ◽  
Vol 43 (5) ◽  
pp. 481 ◽  
Author(s):  
K. F. Smith ◽  
N. M. McFarlane ◽  
V. M. Croft ◽  
P. J. Trigg ◽  
G. A. Kearney
Keyword(s):  
Genetic Variation ◽  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
Seed Mass ◽  
Leaf Length ◽  
Seedling Height ◽  
Seedling Vigour ◽  
Lolium Perenne L ◽  
Early Vigour ◽  
Shoot Mass

Genetic variation for seed mass and components of early vigour were measured on 120 seedlings of each of 18 diploid and 27 tetraploid perennial ryegrass (Lolium perenne L.) cultivars. Seeds of tetraploid cultivars were on average heavier (3.8 mg) than seed of diploid cultivars (2.4 mg). However, there was variation for mean seed mass both within and between ploidy classes and within cultivars. The components of early vigour measured on each of the seedlings were: date of emergence, leaf appearance rate, seedling height (10 days after germination), leaf length and width and dry matter at 33 days after emergence. Mean seed mass of a cultivar was significantly (P<0.05) positively correlated with seedling height, leaf length, leaf width, shoot length and shoot mass. Individual seed mass within a cultivar was significantly associated with all components of early vigour, except the date of emergence of the second true leaf. There was no difference in the rate of emergence of tetraploid and diploid cultivars, although tetraploid cultivars tended to have longer and wider leaves, greater seedling lengths and fewer leaves and tillers than diploid cultivars. There was also evidence of genetic variation for seedling vigour components in perennial ryegrass after seed mass and ploidy effects had been removed during analysis. These data suggest that seed mass has a large positive effect on early vigour of both diploid and tetraploid cultivars of perennial ryegrass and that, in the absence of any specific knowledge of the early vigour characteristics of a given cultivar, seed mass could be used as a surrogate when choosing between cultivars with similar adaptation and performance.

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