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The purpose of this study was to evaluate the performance potential of red bean lines, derived from populations of the first cycle of recurrent selection in the common bean breeding program of the Federal University of Viçosa, Minas Gerais. In the F3:5, F3:6 and F3:7 generations, 243 families from 18 segregating populations were evaluated. These families were conducted by the bulk-within-families method and from the best, 154 lines were obtained and evaluated in the dry season of 2006 (F7: 9) and of 2007 (F7: 10), Coimbra - MG. The estimates of genetic and phenotypic parameters revealed variability among families. The method bulk within F3-derived families proved useful for bean breeding. The most promising lines that may be included in future tests of value for cultivation and use (VCU), and will possibly be recommended for planting in the state of Minas Gerais, were derived from the populations Vermelhinho/AN9022180//Vermelhinho/Vermelho2157, Vermelhinho//Vermelhinho/ IAPAR81,Vermelhinho/LR720982// Vermelhinho/AB136 and Vermelhinho/AB136//Vermelhinho/ Vermelho2157. [ABSTRACT FROM AUTHOR]

• FA models allow G × E studies even for highly unbalanced historical datasets. • G × E studies are valuable tools to optimize resources in sorghum breeding programs. • FA loadings can be successfully used to investigate the main factors affecting G × E. Biomass sorghum has emerged as an alternative crop for biofuel and bioelectricity production. Fresh biomass yield (FBY) is a quantitative trait highly correlated with the calorific power of energy sorghum cultivars, but also highly affected by the environment. The main goal of this study was to investigate the genotype-by-environment interaction (G × E) and the stability of sorghum hybrids evaluated for FBY across different locations and years, using factor analytic (FA) mixed models and environmental covariates. Pairwise genetic correlations between environments ranged from -0.21 to 0.99, indicating the existence of null to high G × E. The FA analysis unveiled that solely three factors explained more than 79% of the genetic variance, and that more than 60% of the environments were clustered in the first factor. Moderate correlations were found between some environmental covariates and the loadings of FA models for environments, suggesting the possible factors to explain the high G × E between environments clustered in a given factor. For example: precipitation, minimum temperature and speed wind were correlated to the environmental loadings of factor 1; minimum temperature, solar radiation and altitude to factor 2; and crop growth cycle to factor 3. The latent regression analysis was used to identify hybrids more responsive to a set of environments, as well as hybrids specifically adapted to a given environment. Finally, FA models can be successfully used to identify the main environmental factors affecting G × E, such as minimum temperature, precipitation, solar radiation, crop growth cycle and altitude. [ABSTRACT FROM AUTHOR]

• A-lines from the sorghum breeding program of Embrapa have the potential for use as parents in the development of superior sweet sorghum hybrids. • The development of a tester with genotype " drydry " and " Ma1Ma1 " is important to develop superior hybrids involving the A, B and R scheme. There is a growing demand for the development of alternative fuels from renewable sources, thus sweet sorghum an autogamous species has potential for bioethanol production. Traditionally recommended cultivars were varieties, however, with the development of cytoplasmic male sterile sweet sorghum lines, sweet sorghum hybrids have become economically viable. The sweet sorghum breeding program of the Brazilian Agricultural Research Corporation (Embrapa Milho e Sorgo) has been developing sweet sorghum hybrids for bioethanol production according to the scheme of A, B and R-lines are used, where A-lines are used as females in the production of hybrid seeds. A and B-lines are isogenic, which differ only its cytoplasm source, sterile and normal, respectively, and fertility restorers R-lines. Thus the objective of this work was to evaluate the genetic potential of new male-sterile sweet sorghum A-lines using testcross hybrids developed with two sweet sorghum R-line as testers for agroindustry characteristics for bioethanol production. Forty testcross hybrids were developed using 20 experimental A-lines and two testers sweet sorghum R-lines. Experiments were conducted at experimental stations in Sete Lagoas-MG and Nova Porteirinha-MG, to evaluate 20 A-lines, two 2 R-lines, the resulting 40 testcross hybrids, and two controls. The 64 treatments were evaluated for days to flowering, fresh biomass yield and total soluble solids (Brix). The data obtained were analyzed using the ASReml package, for the estimation of variance components and the prediction of genetic and non-genetic values via REML/BLUP. Two models were adopted, called Multi-Tester and Single-Tester. The genotypic values of the A-lines when crossed with tester T2, were positive for nine A-lines (12, 17, 6, 20, 18, 16, 19, 11 and 3) with emphasis on A-lines 12, 17 and 6, which were the highest values, respectively, the same tester for the trait FLOW, ten A-lines were positive values (3, 16, 17, 4, 12, 15, 5, 6, 8, 20) with emphasis on 3, 16 and 17. The genotypic values for TSS (Brix) trait of the A-lines when crossed with tester T1 were positive for A-lines (19, 18, 20, 16, 1, 5, and 6) with emphasis on lines 19, 18, 20, and 16, with the highest values, respectively. Only two A-lines showed positive genotypic values for three traits, A-line 16 and 20. These results indicate the need for continuing simultaneous improvement of A-lines for FLOW, FBY, and TSS. A-lines from the sorghum breeding program of Embrapa Milho e Sorgo have the potential for use as parents in the development of superior sweet sorghum hybrids for bioethanol production. The A-lines 6 and 20 have positive genotypic values for three traits, this A-lines has a potential for producing hybrids dedicated to bioethanol production. The T1-L tester was more efficient in discriminating the genetic values between the A lines for TSS, while the T2-L tester for FBY and FLOW. The development of a tester with genotype " drydry " and " Ma 1 Ma 1 " is important in order to develop superior hybrids to produce bioethanol involving the A, B and R scheme. [ABSTRACT FROM AUTHOR]

Genomic selection (GS) aims to incorporate molecular information directly into the prediction of individual genetic merit. Regularized quantile regression (RQR) can be used to fit models for all portions of a probability distribution of the trait, enabling the conditional quantile that "best" represents the functional relationship between dependent and independent variables to be chosen. The objective of this study was to predict the individual genetic merits of the traits associated with flowering time (DFF—days to first flower; DTF—days to flower) in the common bean using RQR and to compare the predictive abilities obtained from Random Regression Best Linear Unbiased Predictor (RR-BLUP), Bayesian LASSO (BLASSO), BayesB, and RQR for predicting the genetic merit. GS was performed using 80 genotypes of common beans genotyped for 380 single nucleotide polymorphism (SNP) markers. Considering the "best" RQR fit models (RQR0.3 for DFF, and RQR0.2 for DTF), the gains in predictive ability in relation to BLASSO, BayesB, and RR-BLUP were 18.75%, 22.58%, and 15.15% for DFF, respectively, and 15.20%, 24.65%, and 12.55% for DTF, respectively. The potential cultivars selected, considering the RQR "best" models, were among the 5% of cultivars with the lowest genomic estimated breeding value (GEBV) for the DFF and DTF traits—the IAC Imperador, IPR Colibri, Capixaba Precoce, and IPR Andorinha were included in the list of early cycle cultivars. [ABSTRACT FROM AUTHOR]

Background: Phosphorus (P) fixation on aluminum (Al) and iron (Fe) oxides in soil clays restricts P availability for crops cultivated on highly weathered tropical soils, which are common in developing countries. Hence, P deficiency becomes a major obstacle for global food security. We used multi-trait quantitative trait loci (QTL) mapping to study the genetic architecture of P efficiency and to explore the importance of root traits on sorghum grain yield on a tropical low-P soil. Results: P acquisition efficiency was the most important component of P efficiency, and both traits were highly correlated with grain yield under low P availability. Root surface area was positively associated with grain yield. The guinea parent, SC283, contributed 58% of all favorable alleles detected by single-trait mapping. Multi-trait mapping detected 14 grain yield and/or root morphology QTLs. Tightly linked or pleiotropic QTL underlying the surface area of fine roots (1–2 mm in diameter) and grain yield were detected at positions 1–7 megabase pairs (Mb) and 71 Mb on chromosome 3, respectively, and a root diameter/grain yield QTL was detected at 7 Mb on chromosome 7. All these QTLs were near sorghum homologs of the rice serine/threonine kinase, OsPSTOL1. The SbPSTOL1 genes on chromosome 3, Sb03g006765 at 7 Mb and Sb03g031690 at 60 Mb were more highly expressed in SC283, which donated the favorable alleles at all QTLs found nearby SbPSTOL1 genes. The Al tolerance gene, SbMATE, may also influence a grain yield QTL on chromosome 3. Another PSTOL1-like gene, Sb07g02840, appears to enhance grain yield via small increases in root diameter. Co-localization analyses suggested a role for other genes, such as a sorghum homolog of the Arabidopsis ubiquitin-conjugating E2 enzyme, phosphate 2 (PHO2), on grain yield advantage conferred by the elite parent, BR007 allele. Conclusions: Genetic determinants conferring higher root surface area and slight increases in fine root diameter may favor P uptake, thereby enhancing grain yield under low-P availability in the soil. Molecular markers for SbPSTOL1 genes and for QTL increasing grain yield by non-root morphology-based mechanisms hold promise in breeding strategies aimed at developing sorghum cultivars adapted to low-P soils. [ABSTRACT FROM AUTHOR]

This paper proposes the construction of a genetic linkage map with 376 recombinant inbred lines (RILs) derived from a cross between Mesoamerican × Andean common bean (Phaseolus vulgaris L) parents based on single nucleotide polymorphism (SNP) markers; and to detect quantitative trait loci (QTLs) associated with seven morpho-agronomic traits: number of days to flowering (DF), number of days to maturity (DM) or crop cycle; plant architecture (ARC); seed yield (YLD); degree of seed flatness (SF); seed shape (SS); and 100-seed weight (SW). A total of 3060 polymorphic SNP markers were used and 2041 segregated at a 1:1 ratio in the RIL population, as expected. These markers were subjected to linkage analysis in each chromosome. The genetic linkage analysis resulted in linkage maps with a total of 1962 markers spanning 1079.21 cM. A total of 29 QTLs associated with seven morpho-agronomic traits were detected on the 11 chromosomes, which explained between 3.83 and 32.92% of the phenotypic variation in DF. A total of 18 candidate genes associated with the detected QTLs were identified and related with biological processes, molecular functions and cellular components. [ABSTRACT FROM AUTHOR]

The objectives of this study were to obtain information about genetic parameters of a partial diallel in common bean, as well as to evaluate the effects of growing seasons, locations and generations in these estimates in order to define the best strategies for the use of diallel analysis as methodology of selection of parents and populations in common bean breeding. Twelve parents were crossed in a partial diallel scheme (5 × 7), and the F1 and F2 generations were evaluated in four experiments (I, II, III, and IV). The effects of seasons were determined in the Experiments I and II, in which the F1 generation was evaluated in two distinct growing seasons. To quantify the effect of locations, we used Experiments III and IV, in which the F2 generation was evaluated in the same season, but at different locations, and to quantify the effect of generations, the experiments II (generation F1) and III (F2 generation) were evaluated in the same season and location. As for grain yield the genetic control varied according to the environment. An effect of interaction on the genetic parameters of the diallel was observed for generation, whereas for grain yield, effects of season and location were observed. For plant architecture, parental combining ability should therefore be estimated using the F1 generation, while for grain yield, both the F1 and F2 can be used. The recombination between the best hybrids is a promising strategy for extraction of superior black bean lines. [ABSTRACT FROM AUTHOR]

The casqued-headed tree frog Trachycephalus atlas Bokermann, 1966 is recorded for the first time in the municipality of Jati, southern region of Ceará state, northeastern Brazil, extending in 72 km east the previous known geographic distribution of this species. An updated geographic distribution map of T. atlas is provided. [ABSTRACT FROM AUTHOR]