Academic literature on the topic 'Half-sib average'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Contents
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Half-sib average.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Half-sib average"
1
Viana, José Marcelo Soriano. "Breeding strategies for recurrent selection of maize." Pesquisa Agropecuária Brasileira 42, no. 10 (October 2007): 1383–91. http://dx.doi.org/10.1590/s0100-204x2007001000003.
Full textAbstract:
The objectives of this work were to analyze theoretical genetic gains of maize due to recurrent selection among full-sib and half-sib families, obtained by Design I, Full-Sib Design and Half-Sib Design, and genotypic variability and gene loss with long term selection. The designs were evaluated by simulation, based on average estimated gains after ten selection cycles. The simulation process was based on seven gene systems with ten genes (with distinct degrees of dominance), three population classes (with different gene frequencies), under three environmental conditions (heritability values), and four selection strategies. Each combination was repeated ten times, amounting to 25, 200 simulations. Full-sib selection is generally more efficient than half-sib selection, mainly with favorable dominant genes. The use of full-sib families derived by Design I is generally more efficient than using progenies obtained by Full-Sib Design. Using Design I with 50 males and 200 females (effective size of 160) did not result in improved populations with minimum genotypic variability. In the populations with lower effective size (160 and 400) the loss of favorable genes was restricted to recessive genes with reduced frequencies.
2
Esmailizadeh, A. K., A. Baghizadeh, and M. Ahmadizadeh. "Genetic mapping of quantitative trait loci affecting bodyweight on chromosome 1 in a commercial strain of Japanese quail." Animal Production Science 52, no. 1 (2012): 64. http://dx.doi.org/10.1071/an11220.
Full textAbstract:
This study was conducted to identify quantitative trait loci (QTL) affecting growth on chromosome 1 in quail. Liveweight data were recorded on 300 progeny from three half-sib families created from a commercial strain of Japanese quail. Three half-sib families were genotyped for nine microsatellite loci on chromosome 1 and QTL analysis was conducted applying the least-squares interval mapping approach. Significant QTL affecting bodyweight at 3, 4, 5 and 6 weeks of age, average daily gain, and Kleiber ratio, an indirect criterion for feed efficiency, were mapped at 0–23 cM on chromosome 1. The detected QTL segregated in two of the three half-sib families and the size of the QTL effect ranged from 0.6 to 1.1 in unit of the trait standard deviation. This is the first report of liveweight QTL segregating in a commercial strain of Japanese quail.
3
Liang, Yongshu, Chao Yan, Xiaojian Qin, Wenbin Nan, and Hanma Zhang. "Construction of three half-sib SSR linkage maps derived from overwintering cultivated rice and segregation distortion loci mapping." Genome 63, no. 4 (April 2020): 239–51. http://dx.doi.org/10.1139/gen-2019-0160.
Full textAbstract:
Segregation distortion is a common phenomenon that has been observed in genetics and plant breeding; however, the mechanism of segregation distortion is unknown. In the present study, three half-sib F2 populations derived from three japonica overwinter (perennial) rice varieties (W1, W2, and W3) crossed to the indica rice variety Minghui725 (MH725) were developed to construct three half-sib linkage maps. We established linkage map lengths of 2032.8, 2317.4, and 2108.7 cM with average intervals of 20.1, 20.5, and 19.7 cM using 101, 113, and 107 SSR markers in W1/MH725, W2/MH725, and W3/MH725, respectively. Discrepancies in marker order and genetic linkage distance occurred in the three half-sib linkage maps due to segregation distortion. A total of 88 markers exhibited segregation distortion across the three linkage maps at P < 0.01 level, 42 segregation distortion loci (SDLs) were detected across the three half-sib populations and exhibited variable LOD value that ranged from 3.2 (SDL2f) to 30.1 (SDL5d), and 13 of the 42 SDLs were repeatedly located at the same chromosomal regions of the previously published hybrid sterility quantitative trait loci. Data from this study provide an extensive archive for investigating the genetic characteristic of overwintering cultivated rice and the future exploration and innovation of overwintering rice breeding.
4
Marcu, Nicu, Marius Budeanu, Ecaterina Nicoleta Apostol, and Raul Gheorghe Radu. "Valuation of the Economic Benefits from Using Genetically Improved Forest Reproductive Materials in Afforestation." Forests 11, no. 4 (March 27, 2020): 382. http://dx.doi.org/10.3390/f11040382.
Full textAbstract:
The research objective was to demonstrate the economic impact of using, in afforestation, forest reproductive materials (FRMs) obtained from seed trees selected in the most valuable Norway spruce populations of the FGRs’ (forest genetic resources’) category. The values obtained for the main growth traits (diameter at breast height (Dbh), tree height (Th), and tree volume (Tv)), both in the FGR and in the closest population (with the same age and growth in similar environmental conditions), were compared. Three comparative trials were analyzed, each belonging to different breeding levels: Open-pollinated (Breţcu, 40 years old), half-sib (Măneciu, 25 years), and full-sib (Comandău, 23 years). The difference in volume/hectare between the FGR and an unimproved neighbor population was economically quantified (€), based on the average price per cubic meter (m3) of spruce wood in Romania; the profit at the end of the rotation period (110 years) was projected taking into account the genetic gain that will result from the use of FRM collected from the FGRs. The average FGR growth results were superior to the unimproved neighbor populations, with 8%–13%, 14%–25%, and 26%–79% for Dbh, Th, and volume/ha, respectively, and the differences increased if the best 10% seed trees of the trials were used. For Th, a five times higher family mean heritability was registered for the pendula trees (compared to pyramidalis) in the half-sib trial, while in the full-sib experiment, the pendula trees (both full and half pendula) again registered higher heritability, but for Dbh, which recommends the pendula selection for different traits in the two trials. These results have led to a rate of profitability between 540 and 3366 €/ha, a value that is predicted to increase until the end of the rotation period, when the genetic gain could generate a profit of 7560 €/ha.
5
Gomez-Raya, L. "Biased Estimation of the Recombination Fraction Using Half-Sib Families and Informative Offspring." Genetics 157, no. 3 (March 1, 2001): 1357–67. http://dx.doi.org/10.1093/genetics/157.3.1357.
Full textAbstract:
Abstract A maximum-likelihood method to estimate the recombination fraction and its sampling variance using informative and noninformative half-sib offspring is derived. Estimates of the recombination fraction are biased up to 20 cM when noninformative offspring are discarded. In certain scenarios, the sampling variance can be increased or reduced up to fivefold due to the bias in estimating the recombination fraction and the LOD score can be reduced up to 5 units when discarding noninformative offspring. Comparison of the estimates of recombination fraction, map distance, and LOD score when constructing a genetic map with 251 two-point linkage analyses and six families of Norwegian cattle was carried out to evaluate the implications of discarding noninformative offspring in practical situations. The average discrepancies in absolute value (average difference when using and neglecting noninformative offspring) were 0.0146, 1.64 cM, and 2.61 for the recombination fraction, map distance, and the LOD score, respectively. A method for simultaneous estimation of allele frequencies in the dam population and a transmission disequilibrium parameter is proposed. This method might account for the bias in estimating allele frequencies in the dam population when the half-sib offspring is selected for production traits.
6
Kuhlman, E. G., and F. R. Matthews. "Variation in virulence among single-aeciospore isolates from single-gall isolates of Cronartiumquercuum f.sp. fusiforme." Canadian Journal of Forest Research 23, no. 1 (January 1, 1993): 67–71. http://dx.doi.org/10.1139/x93-011.
Full textAbstract:
Single aeciospores from single-gall isolates of Cronartiumquercuum (Berk.) Miyabe ex Shirai f.sp. fusiforme previously shown to have virulence toward resistant half-sib loblolly pine (Pinustaeda L.) families 10-5, 11-20, or 29R were propagated in the asexual uredial stage on leaves of oak seedlings. Only 80 of 1086 single aeciospores from a single-gall isolate with virulence towards family 10-5 produced symptoms of infection on the oaks, and 17 infections produced telia directly. Thirty-two single-aeciospore isolates were propagated from the 63 uredinia. Half-sib progeny of 10-5 were inoculated with each of the 32 isolates, and after 9 months incidence of seedlings with galls varied from 46 to 93%. Six isolates produced galls on more than 90% of the seedlings. Average gall length ranged from 30 to 56 mm among the 32 isolate treatments. Similarly, 20 single-aeciospore isolates propagated from two single-gall isolates with virulence towards family 11-20 caused galls on 19–59% of 11-20 progeny. Finally, 12 single-aeciospore isolates propagated from a single-gall isolate with virulence towards family 29R produced galls on 38–91% of the half-sib progeny of 29R. Thus, in three separate experiments virulence among single-aeciospore isolates toward a resistant source ranged from normal to very high.
7
Gonzalez-Benecke, C. A., T. A. Martin, A. Clark, and G. F. Peter. "Water availability and genetic effects on wood properties of loblolly pine (Pinus taeda)." Canadian Journal of Forest Research 40, no. 12 (December 2010): 2265–77. http://dx.doi.org/10.1139/x10-162.
Full textAbstract:
We studied the effect of water availability on basal area growth and wood properties of 11-year-old loblolly pine ( Pinus taeda L.) trees from contrasting Florida (FL) (a mix of half-sib families) and South Carolina coastal plain (SC) (a single, half-sib family) genetic material. Increasing soil water availability via irrigation increased average whole-core specific gravity (SG) and latewood percentage (LW%) by 0.036 and 6.93%, respectively. Irrigation did not affect latewood SG or wood stiffness, but irrigated FL and SC trees had more latewood due to a 29 day longer growing season. Irrigation did not affect the length of corewood production, but irrigated trees had earlier transition ages, producing outerwood ~3 years before rainfed trees. The increase in whole-core SG and LW% was moderate because irrigation promoted earlywood growth in corewood formed before canopy closure, but after year 7, rain-fed and irrigated trees had similar earlywood growth but irrigated trees had more latewood growth, increasing ring SG and LW%. The SC half-sib family had higher SG and greater LW% than trees from FL independent of irrigation due to greater yearly latewood growth. Thus, absence of soil water stress extended seasonal diameter cessation date but did not change latewood SG or wood stiffness.
8
Zhao, Xiyang, Yanyan Pan, Xiaona Pei, Fuwei Wang, Chenglu Wang, Lili Shao, Lihu Dong, and Guan-Zheng Qu. "Forward, backward selection and variation analysis of growth traits in half-sib Larix kaempferi families." Silvae Genetica 68, no. 1 (January 1, 2019): 1–8. http://dx.doi.org/10.2478/sg-2019-0001.
Full textAbstract:
Abstract Tree height and diameter at breast height of 30 half-sib Larix kaempferi families were analyzed at different ages. Analysis of variance revealed a significant difference in growth among different families. Phenotypic variation coefficients of the traits tree height and diameter at breast height among families of different ages ranged from 11.04 % to 31.74 % and 19.01 % to 19.83 %, respectively. Average heritability of tree height and diameter at breast height ranged from 0.87 to 0.96 and 0.93 to 0.96, respectively. Significant positive correlations were observed among all traits at different ages. By the method of multiple-traits comprehensive, six families (L18, L12, L8, L3, L25 and L20) were selected as being elite using a 20 % selection ratio at 12 years of age. Average values of these elite families were 11.15 % and 16.83 % higher than the total average for height and diameter at breast height, and genetic gains were 10.53 % and 15.79 %, respectively. Forty five elite individual plants were selected using a 5 % selection ratio which were 23.47 % and 24.90 % higher than the overall average for height and diameter at breast height, respectively.
9
Maliondo, S. M., and H. H. Krause. "Genotype and soil fertility interaction in the growth of black spruce progeny from a central New Brunswick population." Canadian Journal of Forest Research 15, no. 2 (April 1, 1985): 410–16. http://dx.doi.org/10.1139/x85-066.
Full textAbstract:
Seedlings representing 10 half-sib families from a black spruce (Piceamariana (Mill.) B.S.P.) stand in central New Brunswick were raised in a greenhouse on three different soils, each with two levels of fertility. Seedling growth varied significantly with soil, fertility, and half-sib family. After 7 months mean dry weights, for example, ranged from 0.292 to 0.755 g with soil, 0.174 to 0.936 g with level of fertility, and 0.370 to 0.657 g with family. With soil and fertility considered fixed variables, the family and family–fertility interaction accounted for approximately 3 and 20% of the phenotypic variation in mean seedling dry weight, respectively. Similar variance components were observed for shoot and root weights, and root collar diameter. Based on the family – soil fertility interaction, the population was divided into groups of (i) broadly adapted families showing average performance through the full range of fertility environments, (ii) strong responders, i.e., families performing below average at low fertility, but showing a large fertilization response, and (iii) weak or nonresponders, i.e., families performing poorly in all fertility environments.
10
Barrera-Irigoyen, Cesar Augusto, Aureliano Peña-Lomelí, Natanael Magaña-Lira, Jaime Sahagún-Castellanos, and Mario Pérez-Grajales. "Study of inbreeding in tomatillo (Physalis ixocarpa Brot. ex Horm.)." Revista Chapingo Serie Horticultura 27, no. 3 (2021): 185–98. http://dx.doi.org/10.5154/r.rchsh.2021.03.006.
Full textAbstract:
Only intervarietal and interfamilial hybridization can be carried out in tomatillo. Therefore, the objective was to study the effect of inbreeding in families of four varieties of tomatillo obtained through three generations of mating by fraternal and plant-to-plant crosses. The varieties studied were Tecozautla, Diamante, Manzano and Morado, each represented by three maternal half-sib families (Generation 1). In 2018, plant-to-plant and fraternal crosses were made in selected plants within each family, resulting in full-sib (FSF) and maternal half-sib (MHSF) families, respectively (Generation 2). In 2019, the process was repeated in Generation 2 families, and another generation of FSFs and MHSFs (Generation 3) was obtained. Field evaluation was conducted in 2020. A randomized complete block design with four replications was used, and yield per plant was evaluated in two harvests and total yield per plant, as well as fruit weight, volume and bulk density, in each harvest and average of harvests. Inbreeding depression occurred among generations. Fruit yield, size and volume in the first harvest decreased over generations. The Tecozautla and Diamante varieties showed greater inbreeding depression. The type of cross had a different effect depending on the variety. Fruit size was lower in plant-to-plant crosses in Tecozautla, Diamante and Morado; that is, they generated greater inbreeding depression than the fraternal crosses.