scholarly journals Genetic gain in apomictic species of the genus Paspalum

Revista CERES ◽  
2017 ◽  
Vol 64 (1) ◽  
pp. 60-67 ◽  
Author(s):  
Emerson André Pereira ◽  
Miguel Dall’Agnol ◽  
Karla Médici Saraiva ◽  
Carine Simioni ◽  
Ana Paula Steiner Leães ◽  
...  
Keyword(s):  
Environmental Effects ◽  
Genetic Gain ◽  
Dry Matter ◽  
Block Design ◽  
Direct Selection ◽  
Phenotypic Variance ◽  
Leaf Production ◽  
Apomictic Species ◽  
Degree Of Association ◽  
Selection Of

ABSTRACT The objective of this work was to provide means to obtain genetic gain in apomictic species of the genus Paspalum by identifying traits that simultaneously show high correlation and heritability. Thus, to determine the amount of phenotypic variation due to genetic and environmental effects and the degree of association between leaf dry matter production and other traits of forage interest that are easy to select and measure will bring agility and economy in the selection of forage species. The experiment was conducted in the years 2009/10 and 2010/11 in the municipalities of Eldorado do Sul and Augusto Pestana, RS, Brazil, in a randomized complete block design with three replicates. The increase in the direct selection pressure on total and leaf dry matter of apomictic accesses of the genus Paspalum is enhanced by a greater contribution of genetic effects than environmental effects on the composition of the phenotypic variance. Efficient genetic gain in leaf production is achieved by indirect selection of total dry matter, which is a trait of high heritability and easy to select and measure.

scholarly journals Variability, Association and Selection of Promising Characters for Breeding Creole Maize

2021 ◽  
pp. 31-43
Author(s):  
Yrle da Rocha Fontinele ◽  
Vanderley Borges dos Santos ◽  
Luan de Oliveira Nascimento ◽  
Antônio Carnaúba de Aragão ◽  
Matheus Matos do Nascimento ◽  
...  
Keyword(s):  
Genetic Variability ◽  
Block Design ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Superior Performance ◽  
Direct Selection ◽  
Phenotypic Variance ◽  
Randomized Block Design ◽  
Grain Moisture ◽  
Selection Of

Genetic variability is the main characteristic when seeking to select promising genotypes for plant breeding. Thus, the objective of this work was to investigate the genetic variability in agronomic and morphological characteristics of traditional varieties of maize, in addition to determining the degree of association and the selection of variety and promising characters to be explored in programs of genetic breeding of Creole maize. The experiment was conducted at the Federal University of Acre (UFAC), Rio Branco - Acre, in the 2017/2018 harvest period. A randomized block design was used, with five replications. The treatments were four varieties of Creole maize (V1, V2, V3 and V4) from the Vale do Juruá region and another hybrid cultivar LG 3040 (HI). The morpho-agronomic characteristics were evaluated in the useful area of the plots: days to silking (DS), days to anthesis (DA), plant height (PH) and height ear insertion (HEI), stem diameter (SD), mass of ear (ME), length ear (LE), diameter ear (DE), total grain mass (TGM), mass of 100 grain (M100G), grain moisture (GM) and grain productivity (GP). The data were subjected to analysis of variance and comparison of means. The values of genotypic and phenotypic variance were also estimated, heritability in the broad sense, selection accuracy, phenotypic, genotypic and environmental correlation, in addition to the principal component analysis (PCA). Variations in characteristics were found between the varieties of Creole maize and their interrelations, showing greater influence of ME, PH, TGM, M100G, DE and GP in the expression of the phenotype. Therefore, it is concluded that there is genetic variability in the characteristics evaluated, with emphasis to V4 that showed superior performance allowing direct selection of the characteristics SD, ME, TGM and M100G to be incorporated into an breeding program.

scholarly journals Genetic parameters and estimated genetic gains in young rubber tree progenies

2013 ◽  
Vol 48 (4) ◽  
pp. 411-416 ◽  
Author(s):  
Cecília Khusala Verardi ◽  
Erivaldo José Scaloppi Junior ◽  
Guilherme Augusto Peres Silva ◽  
Lígia Regina Lima Gouvêa ◽  
Paulo de Souza Gonçalves
Keyword(s):  
Genetic Gain ◽  
Genetic Parameters ◽  
Block Design ◽  
Rubber Tree ◽  
First Year ◽  
Genetic Gains ◽  
Selection Gain ◽  
Randomized Block Design ◽  
Using Data ◽  
Selection Of

The objective of this work was to assess the genetic parameters and to estimate genetic gains in young rubber tree progenies. The experiments were carried out during three years, in a randomized block design, with six replicates and ten plants per plot, in three representative Hevea crop regions of the state of São Paulo, Brazil. Twenty-two progenies were evaluated, from three to five years old, for rubber yield and annual girth growth. Genetic gain was estimated with the multi-effect index (MEI). Selection by progenies means provided greater estimated genetic gain than selection based on individuals, since heritability values of progeny means were greater than the ones of individual heritability, for both evaluated variables, in all the assessment years. The selection of the three best progenies for rubber yield provided a selection gain of 1.28 g per plant. The genetic gains estimated with MEI using data from early assessments (from 3 to 5-year-old) were generally high for annual girth growth and rubber yield. The high genetic gains for annual girth growth in the first year of assessment indicate that progenies can be selected at the beginning of the breeding program. Population effective size was consistent with the three progenies selected, showing that they were not related and that the population genetic variability is ensured. Early selection with the genetic gains estimated by MEI can be made on rubber tree progenies.

scholarly journals Direct selection for phenotypic traits in carrot genotypes

2019 ◽  
Vol 37 (3) ◽  
pp. 354-358
Author(s):  
Agnaldo DF de Carvalho ◽  
Giovani O da Silva ◽  
Gabriel E Pereira
Keyword(s):  
Agronomic Traits ◽  
Block Design ◽  
Direct Selection ◽  
Phenotypic Traits ◽  
Crop Breeding ◽  
Breeding Programs ◽  
Randomized Block Design ◽  
Increase Productivity ◽  
Abstract Selection ◽  
Selection Of

ABSTRACT Selection of more productive carrot genotypes is fundamental for crop breeding programs aiming to increase productivity and reduce cost production. Thus, the aim of this work was to evaluate gains from direct selection and to measure its effects on other agronomic traits of interest in carrots. Thirty six carrot genotypes were evaluated in two experiments: the first, sown in the second half of November 2016 and the second one in the first week of March 2017. The experimental plots covered a useful area of 1.5 m2, in transversal rows and 0.10-m double spacing between single rows x 0.20-m between double rows in a randomized block design with 3 replicates. At 90 days, the incidence of leaf blight was evaluated using a note scale and 100 days after sowing, roots were harvested measuring the number and mass of total, commercial and non-commercial roots of each plot. The direct selection of commercial root mass allowed to estimate indirect and expressive gains for most evaluated traits, allowing to select seven genotypes (populations 758, 751, 737, 736, 735, 744 and 742) which can be released as cultivar or for the formation of a broader genetic-based population.

scholarly journals Repeatability estimates and minimum number of evaluations for selection of elephant-grass genotypes for herbage production

2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Erina Vitório Rodrigues ◽  
Rogério Figueiredo Daher ◽  
Geraldo de Amaral Gravina ◽  
Alexandre Pio Viana ◽  
Maria do Socorro Bezerra de Araújo ◽  
...  
Keyword(s):  
Plant Height ◽  
Principal Components ◽  
Dry Matter ◽  
Block Design ◽  
Phenotypic Selection ◽  
Stem Diameter ◽  
Dry Matter Yield ◽  
Elephant Grass ◽  
Minimum Number ◽  
Selection Of

In forage-plants breeding, the selection of superior genotypes has been undertaken through successive harvests in previously established intervals. However, this process involves many steps, the evaluation of many traits, and a great spending with costs and labor. Thus the estimate of the repeatability is essential in improvement of perennials, it allows predicting genotypic value of the individual, the minimum number of evaluations in the selection of genotypes and minimizes resources and time in the selection of promising individuals. The objective of this study was to estimate the repeatability coefficient for morphological traits in elephant grass and determine the number of evaluations needed for phenotypic selection more efficient. The experimental randomized block design with 53 genotypes and two replications. The repeatability coefficients were estimated for variables plant height, number of tillers, stem diameter and dry matter yield, using the methods of Anova, Principal Components and Structural Analysis. We observed significant differences between genotypes (P <0.01) for all variables. The main components provide larger estimates of repeatability when compared to other methods. Estimates of the repeatability coefficients are of high magnitude average for the variables plant height (0.44) number of tillers (0.44) and stem diameter (0.63) and low magnitude for dry matter production (0.27). The Principal Components method requires five, five, two and eleven measurements for plant height, number of tillers, stem diameter and dry matter yield, respectively, with 80% reliability.  

Character Association Study Among Components of Green Fodder Yield in Ricebean

2017 ◽  
Vol 51 (04) ◽  
Author(s):  
Monica Jyoti Kujur ◽  
S. K. Bilaiya ◽  
A.K. Mehta
Keyword(s):  
Plant Height ◽  
Crude Protein ◽  
Dry Matter ◽  
Protein Yield ◽  
Direct Selection ◽  
Path Coefficient ◽  
Dry Matter Yield ◽  
Green Fodder ◽  
Fodder Yield ◽  
Selection Of

Ricebean has been categorized as underutilized crop despite its nutritive quality and fodder yielding ability benign higher than other legumes of Vigna family. In addition to its nutritive value, this crop is fairly resistant to drought and flood conditions. The purpose of this paper is to provide important traits for direct selection of fodder yielding ricebean genotypes through analysis of phenotypic and genotypic association and path coefficient. In the present study, the degree of association between yield and yield contributing attributes were estimated in 85 germplasm lines for nineteen quantitative traits so that direct selection of the promising traits may be effective for the improvement of yield potential of future genotypes of ricebean. Correlation studies indicated that green fodder yield per plant was significantly and positively associated with green fodder yield per day, number of leaves per plant, number of branches per plant, crude protein yield per plant, crude protein yield per plant per day, dry matter yield per plant, dry matter yield per plant per day, leaf stem ratio and plant height at both genotypic and phenotypic levels. Path coefficient revealed that green fodder yield per plant per day has highest direct effect and significant positive correlation towards yield. Other traits, crude protein yield per plant, dry matter yield per plant per day, days to 50% flowering, days to flower initiation and plant height were also found to be important fodder yield indicators in ricebean.

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 Korelasi dan Analisis Lintas Karakter Agronomi Kedelai (Glycine max [L.] Merrill) Keturunan Persilangan Wilis X MLG 2521

2017 ◽  
Vol 16 (1) ◽  
Author(s):  
Nyimas Sa’diyah ◽  
Christian Raymond Siagian ◽  
Maimun Barmawi
Keyword(s):  
Plant Breeding ◽  
Path Analysis ◽  
Block Design ◽  
Flowering Plant ◽  
Direct Selection ◽  
Real Relationship ◽  
Randomized Block Design ◽  
Glycine Max L ◽  
The Relationship ◽  
Selection Of

Soybean is one of the crops that produce seeds with high protein content, as well as used by the inhabitants of Indonesia. Domestic soybean production can not meet the needs of the national soybean thus needs to be improved, one through breeding varieties with superior. One important step in plant breeding is the selection. To save time and costs of selection, it is necessary to determine the estimated correlation between characters  and to determine the causal relationship between characters used path analysis. Through path analysis can be seen directly and indirectly influence between variables forecaster with the response variable. The purpose of this study to obtain information (1) correlation between characters agronomic towards production. (2) direct and indirect effects of agronomic between characters towards production. The research was conducted from October 2013 until January 2014 in the integrated field laboratory of the Faculty of Agriculture, University of Lampung and observations made in Laboratory of Seed and Plant Breeding, University of Lampung. Soybean seeds used were  F5 generation zuriat from Wilis x Mlg 2521,  Willis and Mlg 2521. The treatment laid out in a randomized block design,  2 replications. The results showed that  there was a positive phenotype correlation between character of days to flowering, plant height, number of branches, number of pods, weight of 100 grains with grain weight per plant and there was no correlation between day to harvesting with the seed weight per plant. Direct selection of the most effective  was through the number of pods because number of  pods have a direct effect almost equivalent to the correlation. The relationship between the number of pods  and weight of seeds per plant explained a real relationship. Keywords: correlation, path analysis, selection, soybean

scholarly journals Prediction of genetic gains with selection between and within S2 progenies of papaya using the REML/Blup analysis

2017 ◽  
Vol 52 (12) ◽  
pp. 1167-1177 ◽  
Author(s):  
Tamiris Pereira da Silva ◽  
Francisco das Chagas Vidal Neto ◽  
Júlio César Do Vale
Keyword(s):  
Genetic Gain ◽  
Carica Papaya ◽  
Genetic Parameters ◽  
Block Design ◽  
Stem Diameter ◽  
Average Mass ◽  
Genetic Gains ◽  
Randomized Complete Block Design ◽  
Selection Of

Abstract: The objective of this work was to predict the genetic gains with selection of superior individuals within papaya (Carica papaya) progenies using the REML/Blup analysis. Thirty-six S2 progenies, originated from the Calimosa and Tainung 1 hybrids, and two commercial control checks were evaluated in a randomized complete block design, with four replicates. The following traits were evaluated: heights of plants and first fruit; stem diameter at 12 and 18 months; number of days required for fruiting; number, mass, and average mass of commercial fruit; and number and mass of carpelloid and pentandric fruit. The magnitudes of the genetic parameters indicated that the variability present in most of the characters allows greater genetic gain if the selection is made at the progeny level, and not in individual plants. For selection among progenies, PROT-268, PROT-74, PROT-55, and PROT-22 were the most promising, with the greatest genetic gain for the studied characters. In the selection among and within progenies, the prediction of the gains is higher for the increase in the expression of the number of commercial fruit and for the decrease in the expression of pentandric fruit.

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

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.

scholarly journals SELECTION FOR THE DEVELOPMENT OF BLACK EYE COWPEA LINES

2018 ◽  
Vol 31 (1) ◽  
pp. 72-79 ◽  
Author(s):  
JÉSSICA DANIELE LUSTOSA DA SILVA ◽  
KAESEL JACKSON DAMASCENO-SILVA ◽  
MAURISRAEL DE MOURA ROCHA ◽  
JOSÉ ÂNGELO NOGUEIRA DE MENEZES JÚNIOR ◽  
VALDENIR QUEIROZ RIBEIRO
Keyword(s):  
Grain Yield ◽  
Block Design ◽  
Selection Index ◽  
Direct Selection ◽  
Selection Cycle ◽  
Lattice Design ◽  
Expected Gain ◽  
Selection For ◽  
New Cultivars ◽  
Selection Of

ABSTRACT Cowpea bean is a socioeconomically important legume that contribute to generate employment and income. This species presents great grain variability, and the commercial subclass black eye stands out as a very appreciated grain in Brazil and abroad, thus requiring the development of new cultivars. The objective of this work was to evaluate and select lineages of commercial black eye cowpea, based on simultaneous, and direct selection. First, 105 progenies and four controls were evaluated using the Federer's augmented block design. Seventy-seven progenies, selected from this evaluation-first selection cycle-and four controls were evaluated in three environments, using a simple 9×9 lattice design. Based on this evaluation, the second selection cycle was possible, resulting in 24 progenies. The gain by direct selection was lower than the predicted gain for grain yield in the first cycle, indicating that the selection was not effective. This result was probably due to the reduced genetic variability caused by the selection pressure. In the second cycle, the predicted and observed gains were similar, indicating that much of the expected gain was observed. The predicted and observed gains, with simultaneous selection based on the rank sum selection index, were similar in the first and second cycle. The simultaneous and direct selections resulted in genetic gains for grain yield in the two selection cycles, making it possible the selection of high grain yield lineages.

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