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Copyright of Revista Facultad Nacional de Agronomía Medellín is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this study was to compare the method BLUPIS (best linear unbiased prediction individual simulated) with mass selection in terms of efficiency in identifying the best genotypes in sugarcane (Saccharum officinarum L.) families. Mass selection was performed by two breeders with 25 yr of experience. The BLUPIS procedure selected families with higher means for tons of cane per hectare (TCH) than the over-all mean. The number of plants selected per family was calculated by nk = (ĝk / ĝj )nj, where ĝk indicates the genotypic value of the kth family; ĝj the genotypic value of the best family; and nj is equal to the number of plants selected in the best family, determined as nj = 45 in this study. Out of 20 best clones forwarded to the third test phase (T3), BLUPIS selected all in the first test phase (T1) and mass selection only two. Therefore, 100% of the clones in the second test phase (T2) had been selected by BLUPIS. The BLUPIS was most efficient in detecting the best genotypes, since all clones that were promoted up to phase T3 were descendants from the best families. The BLUPIS method should be applied in sugarcane breeding programs to ensure the selection of the best genotypes. [ABSTRACT FROM AUTHOR]

Forage breeding can be extraordinarily complex because of the number of species, perenniality, mode of reproduction, mating system, and a variable genetic correlation between spaced plants and sward plots. Aiming to compare eight forage breeding methods for direct selection gain and correlated response, different scenarios of trait heritability and genetic correlation have been evaluated based on deterministic equations of expected (theoretical) breeding accuracy applied to half-sib progenies evaluated in spaced-plant trails, sward-plot trials, or both. Relative efficiency for each method is given in relation to individual selection. Methods differ most when heritability is lower than 0.3, which coincides with the majority of the situations met by forage breeders. Genetic gain of best linear unbiased prediction (BLUP)-based methods is superior to all other methods for trait heritability lower than 0.3, independent of field-trail plot methods, except for parental selection. Methods based on BLUP have also shown higher efficiency when the genetic correlation between spaced-plant and sward-plot trials evaluations of a trait is lower than 0.7 and indirect-trait heritability is lower than 0.3. The choice of forage breeding method should include consideration of the mode of reproduction and the target-trait heritability. The benefits of BLUP-based selection methods should receive more serious consideration by forage breeders. [ABSTRACT FROM AUTHOR]

Best linear unbiased prediction (BLUP) is the method primarily used for genetic evaluation in animal and forest species breeding. The objective was to present theory and application of BLUP in family selection. Statistical models aim to predict the breeding values of parents of half-sib and inbred families and the individual or average additive values of parents of full-sib families. We analized the expansion volume (EV) and grain yield of halfand full-sib families and of inbred progeny from the Vicosa popcorn {Zea mays L. subsp. mays [syn. Zea mays L. subsp. everta (Sturtev.) Zhuk.}} population in two selection cycles. The noninbred families were evaluated in a 14 by 14 simple lattice, and the inbred progeny were assessed in the incomplete block design. The additive-dominant model was fitted for yield of full-sib families of the second cycle and across generations for yield of full-sib families and EV of inbred progeny. Additive x additive epistasis was trot significant for EV and yield of half-sib families. Although the predictions of breeding values in the additive and additive-dominant models are positively correlated, different sets of parents were included in the top 10% of breeding values from the two models. Therefore, the additive-dominant model should be fitted wherever possible. [ABSTRACT FROM AUTHOR]

J. curcas (physic nut) is one of the most promising oilseeds for biofuel production and the knowledge about genetic parameter estimates is important for its breeding. Here, we evaluated 121 families, from 48 to 60 months of age, aiming genetic evaluation and selection. The trial was set up in an 11 x 11 lattice design, with three replications and 4-plant plot. The traits evaluated were fruit yield (FY), grain (GY) and oil yield (OY), fruit husk percentage (FH) and seed oil content (OC). Individual heritabilities were low (0.19 to 0.23), requiring accurate selection and improvement methods. Moderate repeatabilities were observed for FY (0.54), GY (0.52), OC (0.30) and OY (0.51), indicating that the families evaluated maintained relative superiority over the years. With selection of the 20 best individuals, the predicted genotypic gains (66%) were greater than the additive gains (56%), indicating greater possibilities of success from cultivation of clones. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the genotype x environment interaction and to estimate the genetic components of variance and mean using mixed models in early selection of 238 clones of Pinus taeda propagated by somatic embryogenesis. The experiment consisted of a complete blocks design, with 12 replications, with one plant per plot, in four environments, at 1, 3, and 4 years of age. Estimates of heritability and of genetic gains in the evaluated environments showed good prospects for selection of superior genotypes. The effect of genotype x environment interaction was pronounced for all traits investigated. With the simultaneous selection for stability and adaptability, 10% genetic gain was obtained in relation to the mean of the commercial controls. This estimated gain indicates that the somatic embryogenesis technique has been effective in propagation of clones with good productive potential. [ABSTRACT FROM AUTHOR]

Highlights • Genetic correlations of low to moderate magnitude were observed between harvests. • Multiple-trait BLUP / Additive Index procedure allowed for the genetic selection. • This procedure can be efficiently applied on Jatropha curcas breeding. Abstract Despite being a species with great potential for biodiesel production, little research has been done on the breeding of Jatropha curcas , mainly with respect to its yield across harvests. Thus, the present study was carried out to analyze longitudinal data via multiple-trait Best Linear Unbiased Prediction (BLUP) for the genetic improvement of Jatropha curcas. The experiment was set up as a randomized block design with two blocks and five plants per plot. The seed yield of 730 individuals of 73 half-sib families was evaluated over six years. Variance components and genetic parameters were estimated via Restricted Maximum Likelihood (REML). The Additive Index was used for ranking and selection purposes. Genetic correlations of low to moderate magnitude were observed between pairs of harvests. The Multiple-trait BLUP / Additive Index procedure allowed for the selection of superior families based on the predicted genetic values, considering all the harvests. Therefore, it can be efficiently applied in the breeding of Jatropha curcas. [ABSTRACT FROM AUTHOR]

Oil palm has stood out among the promising species for biofuel production and plant improvement through cloning superior individuals is the technology that contributes most to increase oil production. However, there are no studies on the genotypes behavior regarding both in vitro performance and yield potential simultaneously. By this mean, the objective of this paper was to study the genetic control of the related characteristics to the oil palm cloning process, and to identify responsive genotypes within a collection of 32 elite materials of a commercial planting in order to select the superior genotypes for the formation of a clonal garden. Callogenesis and production of embryogenic lines, which are main characteristics related to the cloning process, presented genetic control, verified through estimates of genetic parameters: heritability, coefficient of relative variation, and selective accuracy; also indicating efficiency in the selection of superior genotypes within the evaluated set. Genotypes A-13, A-14, A-18, A-20 and A-21 were selected as superior genotypes for both characteristics, such as oil yield and in vitro performance, due to formation of embryogenic lines. This has been the first study investigating the genetic control of the cloning capacity aiming to the selection of genotypes for a clonal garden formation. [ABSTRACT FROM AUTHOR]