scholarly journals JUVENILE-MATURE GENETIC CORRELATIONS IN Pinus taeda CLONES PROPAGATED VIA SOMATIC EMBRYOGENESIS

2016 ◽  
Vol 40 (2) ◽  
pp. 255-267
Author(s):  
Poliana Coqueiro Dias ◽  
Aloisio Xavier ◽  
Marcos Deon Vilela de Resende ◽  
Fabrício Antonio Biernaski ◽  
Regiane Abjaud Estopa ◽  
...  
Keyword(s):  
Somatic Embryogenesis ◽  
Pinus Taeda ◽  
Genetic Correlations ◽  
Estimation Procedure ◽  
Early Selection ◽  
Selection Efficiency ◽  
Selection For ◽  
Rotation Age ◽  
High Selection ◽  
Selection Of

ABSTRACT This study aimed to estimate the genetic correlation among selection ages (juvenile - adult) and efficiency of early selection for the height, diameter, and volume traits of individuals from Pinus taeda families propagated via somatic embryogenesis. This study was carried out by genetic-statistical analysis, estimation procedure of variance (Reml), and prediction components of breeding values (Blup), using the Selegen-Reml/Blup software. Genetic correlations among juvenile ages and rotation age were performed by applying the linear model developed by Lambeth (1980). In accordance with results of the established model, the early selection can be performed in clones of Pinus taeda with high selection efficiency. Ages from 4 to 6 years old are enough to select Pinus taeda clones propagated via somatic embryogenesis for harvesting at 8 and 12 years old; and 6 to 10 years old are enough to select them for harvesting at 20 years old. On the basis of the genetic correlations estimates from the environments, the clones' selection of Pinus taeda propagated via somatic embryogenesis should be developed specifically for each environment. The clones' selection can be performed considering the diameter due to the high correlation between volume and diameter.

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

2013 ◽  
Vol 62 (1-6) ◽  
pp. 277-284 ◽  
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.

Use of a Pilodyn for the indirect selection of basic density in Eucalyptusnitens

1996 ◽  
Vol 26 (9) ◽  
pp. 1643-1650 ◽  
Author(s):  
B.L. Greaves ◽  
N.M.G. Borralho ◽  
C.A. Raymond ◽  
A. Farrington
Keyword(s):  
Genetic Correlations ◽  
Basic Density ◽  
Indirect Selection ◽  
Selection Intensity ◽  
Selection Efficiency ◽  
Direct Assessment ◽  
Pilodyn Penetration ◽  
Selection For ◽  
High Repeatability ◽  
Selection Of

Six hundred 7-year-old Eucalyptusnitens (Dean & Maid.) trees from 50 open-pollinated families were measured for wood density and Pilodyn penetration across two contrasting sites in eastern Victoria, Australia. Eight Pilodyn observations, two from each of four aspects, were made at a height of 1.3 m. Density was measured on whole disks cut from 1.3 m. Heritability of Pilodyn penetration and disk density at 1.3 m were 0.60 and 0.73, respectively. Phenotypic and genetic correlations between Pilodyn penetration and density at 1.3 m were −0.59 and −0.92, respectively. The high repeatability of Pilodyn penetration (0.90) suggests that only two observations per tree would be required for indirect selection of density. Direct index selection for density gave an expected 13% gain (assuming a selection intensity of 1%), compared with a 11% gain by using indirect Pilodyn selection, a selection efficiency of 84%. However, Pilodyn sampling is faster, cheaper, and not destructive, thus resulting in overall higher expected gains for selection of trees or culling of seedling seed orchards in comparison with the more destructive direct assessment of density.

Genetics of wood stiffness and its component traits inPinus radiata

2006 ◽  
Vol 36 (5) ◽  
pp. 1165-1178 ◽  
Author(s):  
Heidi S Dungey ◽  
A Colin Matheson ◽  
Dominic Kain ◽  
Robert Evans
Keyword(s):  
New Zealand ◽  
Genetic Correlations ◽  
Microfibril Angle ◽  
Early Selection ◽  
Stiffness Modulus ◽  
Wood Stiffness ◽  
South Wales ◽  
Age Related ◽  
Component Traits ◽  
Selection For

The potential for breeding Pinus radiata D. Don to improve wood stiffness (modulus of elasticity, MoE) was examined by obtaining pith-to-bark cores from trees at breast height in two independent genetic trials. The effectiveness of early selection for stiffness and indirect selection on the component traits, microfibril angle (MfA) and wood density, was determined as well as the age-related changes in the genetic variation of these traits. The first trial comprised 50 open-pollinated families in the central North Island, New Zealand. The second trial comprised 20 control-pollinated families in New South Wales, Australia. The genetic control of MfA, density, and MoE was found to be high in the corewood and moderate in the outerwood. Estimated genetic correlations suggested that early selection for most traits would be successful but could be carried out slightly earlier at the New Zealand site than at the Australian site. To maximize gain in the corewood, selection for MoE and MfA would be most effective around rings 4-8. There were no adverse correlations between MoE and MfA or density, implying that selection for MoE would also improve MfA and density.

scholarly journals Age-related Trends in Genetic Parameters for Jack Pine and Their Implications for Early Selection

2007 ◽  
Vol 56 (1-6) ◽  
pp. 242-252 ◽  
Author(s):  
Y. H. Weng ◽  
K. J. Tosh ◽  
Y. S. Park ◽  
M. S. Fullarton
Keyword(s):  
Genetic Parameters ◽  
Genetic Correlations ◽  
Jack Pine ◽  
Single Site ◽  
Early Selection ◽  
Narrow Sense ◽  
Narrow Sense Heritability ◽  
Age Related ◽  
Different Ages ◽  
Rotation Age

Abstract Trends in genetic parameters for height growth of jack pine (Pinus banksiana Lamb.) were examined over three series of family tests throughout New Brunswick. Data were analyzed for each site and across sites within each series. Although individual narrow sense heritability estimates from single-site analyses varied substantially from site to site and showed no consistent age-related pattern, the estimates from across-site analyses showed an increasing trend to age 20. Similar as individual narrow sense heritability, the coefficient of additive genetic variance estimated from single site showed more variation than those estimated from across site analyses. Age-age (type-a) genetic correlations for height were high and could be well predicted by a LAR2 model, where LAR is the natural logarithm of the ratio between two ages at assessment. Type-b genetic correlations were high and of similar magnitude at different ages. Genetic correlations between height at different ages and volume at one-half rotation age were generally high. Taking the volume at one-half rotation age as the target trait, the selection for target trait from early selection at ages 5~7 could be more efficient per year than direct selection.

scholarly journals Influence of Ascites Syndrome on Growth Pattern of Chickens Reared at Normal or Cold Ambient Temperature

2015 ◽  
Vol 15 (2) ◽  
pp. 373-385 ◽  
Author(s):  
Karim Hasanpur ◽  
Mohammadreza Nassiry ◽  
Ghasem Hosseini Salekdeh ◽  
Rasul Vaez Torshizi ◽  
Abbas Pakdel ◽  
...  
Keyword(s):  
Selective Breeding ◽  
Genetic Correlations ◽  
Case Selection ◽  
Rapid Growth Rate ◽  
Simultaneous Selection ◽  
Selection For ◽  
Financial Losses ◽  
Selection Of ◽  
Meat Type ◽  
Ascites Syndrome

Abstract Ascites syndrome (AS) is a metabolic disorder usually seen in highly improved meat-type broiler strains. This syndrome causes major financial losses to the poultry industry. Previously it was believed that AS incidence was a side effect of intense selection for rapid growth rate (GR) or higher market weight. If this belief is the case, selection for further increase in GR will not be rational. However, it was later understood that there were significant genetic variations for both GR and susceptibility/resistance to AS; thus selective breeding could be helpful in diminishing the incidence of AS while improving GR. Furthermore, it was hypothesized that genes controlling the GR were not genetically dependent on those genes controlling susceptibility to AS. In the current research, we aimed to study the association of GR traits with AS% in a pure sire line. A total of 1458 1-day-old chicks from 67 sire families were used. The results revealed that ascitic chicks were not significantly superior in early GR traits (i.e. before day 28) than the healthy ones. At later ages, probably due to the commencement of the syndrome, the ascitic chicks were significantly lighter in body weight (BW) than their healthy counterparts. The lack of significant genetic correlations between the GR traits and AS% indicated that there was considerable scope for simultaneous selection of birds for increased BW and GR while controlling susceptibility to AS.

scholarly journals Age-age correlations and prediction of early selection age for diameter growth in a 35-years old Pinus brutia Ten. Genetic experiment

2021 ◽  
Vol 30 (3) ◽  
pp. e010-e010
Author(s):  
Yusuf Kurt ◽  
Keyword(s):  
Eastern Mediterranean ◽  
Genetic Correlations ◽  
Tree Height ◽  
Common Garden ◽  
Ground Level ◽  
Forest Tree ◽  
Early Selection ◽  
Diameter Growth ◽  
Pinus Brutia ◽  
Rotation Age

Aim of study: Forest geneticists developed various methods to predict an early selection age for forest tree species in order to shorten the breeding cycles. This study aims to estimate age-age correlations among diameter growth of trees at different ages and predict early selection age for Pinus brutia Ten. Area of study: P. brutia populations in the study were sampled from the most productive distribution range of the species, which is an important forest tree in the eastern Mediterranean Basin. To understand genetic variation and determine early selection age for the species, a common garden experiment was established in two test sites near Antalya city, Turkey, in 1979. Material and methods: Wood increment cores at breast height were collected at age 30 years, and diameters (dbh) were measured for the ages 13, 15, 19, 21, 23, 25, and 27 years on the cores. Diameters at ground level (dgl) and dbh were also measured on live trees at age 35. Variance components, age-age correlations, heritability and selection efficiency were estimated for the diameters. Main results: Age-age genetic correlations for diameters were high (mostly > 0.90). Genetic correlations between dgl (at age 35) and dbh (at all measurement ages) ranged from 0.84 to 0.99. Regressions of genetic correlation on natural log of age ratio (LAR) of juvenile age to older age were significant (P < 0.0001). Selection efficiencies estimated by employing the prediction equation indicated that for rotation age 40, the optimum selection age would be between 3 to 5 years, and for rotation age 100 it would be between 5 to 9 years. Research highlights: The results of this study provide information that can be used to find early selection ages in P. brutia. On relatively poor test sites most trees may not attain enough height growth to have measurable dbh trait. In such cases, dgl and/or tree height traits (both of which are highly correlated with dbh traits of all ages) can be measured and used instead of dbh trait for evaluations.

The genetic basis of growth, reproduction, and maternal environment in Romney ewes. II.* Genetic covariation between hogget characters, fertility, and maternal environment of the ewe

1972 ◽  
Vol 23 (1) ◽  
pp. 149 ◽  
Author(s):  
TS Ch'ang ◽  
AL Rae
Keyword(s):  
New Zealand ◽  
Genetic Gain ◽  
Predictive Accuracy ◽  
Genetic Correlations ◽  
Direct Selection ◽  
Maternal Environment ◽  
Subsequent Fertility ◽  
Selection For ◽  
Reproductive Characters ◽  
Selection Of

This paper is the second in a series of studies on the genetic variation and covariation in growth and reproductive characters of the New Zealand Romney sheep. The data used were obtained over a period of 11 years (1955–1965 inclusive) from a random bred experimental flock maintained at Massey University, Palmerston North, New Zealand. Phenotypic correlations were estimated between the ewe's liveweights, oestrous performance at the hogget stage (from weaning to about 14 months), and her subsequent fertility (number of lambs born per ewe) at the first lambing (2-year-old) or over several lambings. These correlations were compared from the viewpoint of accuracy in predicting, prior to first mating, a young ewe's potential fertility over one or several lambings during her own lifetime. The results suggest that for this purpose, the predictive accuracy of the hogget characters is generally low but comparable with, and in some cases, substantially greater than, that obtainable from fertility records belonging to the dam of the young ewe. Three different methods were used to estimate the genetic correlations. In general, the pattern of genetic correlations, either within the hogget characters or between them and fertility of the ewe, is predominantly one of positive values ranging from moderate size to unity. In contrast, most of the maternal genetic correlations were negative. The relative efficiency of indirect versus direct selection for genetic gain in various characters was examined under different assumptions made with regard to the maternal effect. Indirect selection, based on the measurement of hogget (yearling) liveweight or number of hogget oestruses, for genetic gain in fertility of the Romney ewe is expected, on present evidence, to be more efficient than direct selection. Of the two characters, hogget liveweight is likely to find wider application because it can be more easily measured. _________________ *Part I, Aust. J. Agric. Res., 21: 115 (1970)

scholarly journals Genotypic values and genetic correlations for components and oil content of bunch of hybrids between caiaué and dendê

2021 ◽  
Vol 17 (1) ◽  
pp. 79-92
Author(s):  
Alessandra Ferraiolo de Freitas ◽  
Ricardo Lopes ◽  
Raimundo Nonato Vieira da Cunha ◽  
Antônio José de Abreu Pina ◽  
Marcos Deon Vilela Resende ◽  
...  
Keyword(s):  
Oil Content ◽  
Genetic Correlations ◽  
Breeding Population ◽  
Indirect Selection ◽  
Lower Proportion ◽  
Breeding Programs ◽  
Physical Composition ◽  
Selection For ◽  
Positive Correlations ◽  
Selection Of

Interspecific hybridization between Elaeis oleiferaand Elaeisguineensis(HIE OxG) is explored in plant breeding programs to meet the demand for resistant cultivars to fatal yellowing, which is the biggest phytosanitary problem in E. guineensisplants in South America, including Brazil. In addition to resistance to fatal yellowing, cultivars should have high oil yield, which depends directly on bunch production and oil content in the bunches (O/FFB). The obtaining of genetic gains in O/FFBfor OxG requires information on the genotypic values of the breeding population and the understanding of how the components of the bunch are related to this characteristic in this type of material. Thus, the objective of this work was toestimate genotypic values and genetic correlations for bunch components and analyze the potential of using these components in the selection of gains for O/FFB. The physical composition and oil content in mesocarp of 840 bunches from 39 HIE OxG F1 progenies were analyzed. Genotypic values for bunch components were estimated using the procedure REML/BLUP andwere obtained from genetic correlations between them. All evaluated components presented genetic variation with possibility of gains through selection, especially the oil content in the bunch (O/FFB), which presented variability above 23%. The selection for O/FFBwill mainly result in bunches with a higher fruit proportion over the weight of the bunch (TF/FFB), greater oil contents in mesocarp of normal and parthenocarpic fruits, and lower proportion of empty spikelets. Considering the high and positive correlations between O/FFBand the evaluated characteristics and the practicality of evaluation, the characteristics with higher potential for indirect selection to increase O/FFBare TF/FFBand proportion of mesocarp in normal fruits.

scholarly journals Multi-Level Genetic Variation and Selection Strategy of Neolamarckia cadamba in Successive Years

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1455
Author(s):  
Qingmin Que ◽  
Chunmei Li ◽  
Buye Li ◽  
Huiyun Song ◽  
Pei Li ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Tree Species ◽  
Growth Traits ◽  
Genetic Correlations ◽  
Wood Products ◽  
Early Selection ◽  
Selection Efficiency ◽  
Age Related ◽  
Multi Level ◽  
Variation And Selection

Neolamarckia cadamba (Roxb.) Bosser is a tropical evergreen broadleaf tree species that could play an important role in meeting the increasing demand for wood products. However, multi-level genetic variation and selection efficiency for growth traits in N. cadamba is poorly characterized. We therefore investigated the efficiency of early selection in N. cadamba by monitoring the height (HT), diameter at breast height (DBH), and tree volume (V) in 39 half-sib families from 11 provenances at ages 2, 3, 4, 5, and 6 years in a progeny test. Age-related trends in growth rate, genetic parameters in multi-level, efficiency of early selection, and realized gain in multi-level for growth traits were analyzed. The result showed that genetic variation among families within provenances was higher than that among provenances. The estimated individual heritability values for the growth traits ranged from 0.05 to 0.26, indicating that the variation of growth traits in N. cadamba was subject to weak or intermediate genetic control. The age–age genetic correlations for growth traits were always positive and high (0.51–0.99), and the relationships between the genetic/phenotypic correlations and the logarithm of the age ratio (LAR) were described well by linear models (R2 > 0.85, except the fitting coefficient of genetic correlation and LAR for HT was 0.35). On the basis of an early selection efficiency analysis, we found that it is the best time to perform early selection for N. cadamba at age 5 before half-rotation, and the selection efficiencies were 157.28%, 151.56%, and 127.08% for V, DBH, and HT, respectively. Higher realized gain can be obtained by selecting superior trees from superior families. These results can be expected to provide theoretical guidance and materials for breeding programs in N. cadamba and can even be a reference for breeding strategies of other fast-growing tree species.

scholarly journals Early selection for resistance to cacao witches’ broom in new parental combinations

2021 ◽  
Vol 47 (2) ◽  
pp. 88-95
Author(s):  
José Luis Pires ◽  
Edna Dora Martins Newman Luz ◽  
Antônio Alves Pimenta Neto
Keyword(s):  
Recurrent Selection ◽  
Early Selection ◽  
Additive Effects ◽  
Dominant Inheritance ◽  
Moniliophthora Perniciosa ◽  
Selection For ◽  
Selection Of ◽  
Better Than

ABSTRACT Progenies from 69 crosses between parents obtained by recurrent selection for resistance and yield were inoculated with Moniliophthora perniciosa basidiospores. The symptoms were evaluated and compared with those in the equally inoculated progenies of Catongo, SIC 23 and SCA 6. Forty-three of the new progenies did not differ statistically from SCA 6, while 10 new progenies were statistically better than this control. The female parents that can be highlighted are (P4B x SCA 6), (MA 16 x SCA 6), (CEPEC 86 x SCA 6), and the EET 75 clone. The best male parents were (CAB 214), (CAB 208) and (P4B x OC 67), which did not differ from each other. This study proved the existence of gene combinations between fathers and mothers, the occurrence of additive effects and the dominant inheritance of these factors, which should allow the selection of clones with higher resistance levels and durability.

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