Resumo em Inglês:

Abstract Bean breeding programs have focused on the generation of early bush cultivars with higher yields, commercial acceptance and resistance to crop-limiting diseases. This study prioritized the nutritional quality in terms of iron (Fe) and zinc (Zn) content in bean grains grown in three high tropical environments. Two bush bean cultivars and five climbing bean cultivars were evaluated. The mineral content of the grains was determined with atomic absorption spectroscopy. The results indicated that the bush genotypes Bacatá and Bianca are biofortified with Fe and Zn and the climbing cultivar Sutagao is biofortified with Zn. Statistical differences were found between genotypes (G), environments (E) and GxE interactions. According to the AMMI stability value (ASV), the cultivars Sutagao, Bianca and Iraca were stable, whereas Bacatá, which was the one with the highest nutritional quality, was moderately stable. The Simijaca environment showed an adequate edaphic contribution to bean production with nutritional quality.

Resumo em Inglês:

Abstract Cotton is an essential worldwide commodity, and Brazil ranks fourth in world production and second in export. The present work aimed to gather the genealogies and estimate the genetic base of 109 Brazilian cotton cultivars released from 1932 to 2021. Twelve of the 68 ancestors identified contributed with 52.03% of the genes, and 33% of the cultivars resulted from the direct selection from landraces or old cultivars, evidencing a narrow genetic base. Over time, especially after 1990, the increases in the number of cultivars released and number of ancestors added to the breeding programs were driven by the need to reduce the cultivars' cycle for coexistence with pests and to make them suitable for mechanized cultivation in the new agricultural frontiers. However, Brazilian cotton cultivars still have a narrow genetic base, with the important participation of the ancestors CNPA SRI3, CKR 100W, C-77 and Express.

Resumo em Inglês:

Abstract The study of adaptability and yield stability is essential for the selection and recommendation of new cultivars. Thus, this study determined the adaptability and yield stability of black bean genotypes for cultivar recommendation using a GGE biplot. To this end, nine trials were carried out at different locations in the state of Rio de Janeiro. Eleven genotypes were evaluated in three growing seasons, in a randomized block design, with three replications. Adaptability and stability of grain yield were analyzed by the GGE biplot method. The effects of genotypes, environments and of the genotype - environment interaction were significant, which explained the different responses of the genotypes to the tested environments. The GGE biplot analysis revealed Macaé as an ideal district for testing and high yield, adaptability, and stability of performance were observed for genotype CNFP 15290, which can be recommended for grain production in the state of Rio de Janeiro.

Resumo em Inglês:

Abstract Dolichos bean is grown in environments with short and long crop growth seasons. Development and deployment of cultivars with flowering time (FT) that matches prevailing crop growth season help maximize their productivity in the environments to which they are targeted. Dependable knowledge on genetic basis of FT enables the use of the most appropriate selection strategy to breed cultivars with desired FT. We unraveled the genetic basis by detecting QTL controlling FT using SSR markers following selective genotyping strategy (SGS) in F2 mapping population (MP). We evaluated the effectiveness of SGS as compared to entire MP genotyping strategy (EGS) to detect QTL controlling FT. Our results suggest that alleles at two SSR markers (LPD 25 and LPD 190) are linked to QTL controlling FT in both SGS and EGS. Our results provide adequate evidence for comparable statistical power of SGS relative to EGS for detection of QTL controlling FT.

Resumo em Inglês:

Abstract The aim was to study the genetic control of the agronomic efficiency at low N availability in maize. Experiments were conducted in seven environments in a square lattice design with 49 hybrids, consisting of 48 crosses and one commercial hybrid, evaluated with and without application of N in top dressing. Grain yields with (GYHN) and without (GYLN) application of nitrogen in top dressing were assessed, and these traits were used to calculate the agronomic efficiency at low N availability (AELN) and the harmonic mean of the relative performance (HMRP). According to the joint analysis of variance of the diallel crosses and the estimates of the general and specific combining abilities, these traits were highly significant. Note that in general AELN was controlled by non-additive genetic effects and the hybrids H7, H3, H47 and H10 and the lines IG3-2, IG3-1, IG4-5, IG4-1 and IG4-6 show higher grain yield without top dressing.

Resumo em Inglês:

Abstract The aim was to investigate the differences between maize hybrids for their agronomic yield and their agro-energy potential. The study was conducted in Palotina and Assis Chateaubriand, Paraná, Brazil. The treatments were composed of 10 maize hybrids (DKB290 [non-GMO], DKB315, DKB340, DKB290, Formula, Defender, Status, 2B810, 30F53, BG7330), which were evaluated for grain moisture and yield, starch content, total soluble solids content, ethanol content in the juice and ethanol yield. The important factors for the result are related to grain yield and the quality of the harvested grains, and agronomic performance of these hybrids may differ according to each crop year. Hybrid 30F53 stood out positively for all variables. Hybrid DKB315 showed the highest ethanol yield and high grain yield, and insignificant grain quality was not enough to result in a decline in ethanol yield.

Resumo em Inglês:

Abstract Twenty six sweet cassava clones were evaluated in two agricultural years, in randomized block design, with 3 replications and plots with 25 plants. The harvests were at 12 months after planting, in both years. The traits evaluated were root yield (RY), dry matter content (DMC), total carotenoids content (TC), β-carotene content (BC), trans-β-carotene content (TrBC) and total cyanide content (TCy). Genotype was significant (P<0.05) in all traits. Broad-sense heritability estimates at the plot level (hmg2 ) ranged from 77% (RY) to 93% (TC and TrBC), while the accuracy ranged from 0.88 (RY) to 0.96 (BC and TrBC). The genetic correlations among TC, BC and TrBC were high (0.96 to 0.99) and significant, and the genetic correlations involving these traits and TCy were negative. These results demonstrate the existence of great genetic variability in characteristics important to cassava biofortification and, consequently, great perspectives in the breeding for this purpose.

Resumo em Inglês:

Abstract This study aimed to investigate the presence of maternal effect on the inheritance of flax seed coat color. Direct and reciprocal crosses were performed between four yellow flax seed lines and two brown flax seed cultivars. F1 and F2 populations of direct and reciprocal crosses were evaluated for coat color. Four F2 populations were selected for analysis of coat color in the F3 generation. The phenotypic segregation pattern was assessed by the chi-square test. The nuclear genotype of the female parent influenced all F1, F2, and F3 populations. F1 and F2 seeds were always equal to the phenotype of the female parent. F3 populations had a 3:1 ratio of plants producing yellow and brown seeds. The maternal effect resulted from the transfer of gene products from maternal cytoplasm to offspring, with evidence of the effect of a single gene with a dominant allele for the yellow phenotype.

Resumo em Inglês:

Abstract The flax cultivar CISJU21, developed by the crop breeding program of the UNIJUÍ, was the result of selection for plants with early flowering, a shorter cycle, greater capsule diameter, optimized weight and higher number of grains per plant, with high yield stability and grain yield in the tested scenarios.

Resumo em Inglês:

Abstract Cultivars URS OLADA and URS POENTE, with superior agronomic performance were bred by the Oat Breeding Program of UFRGS. These cultivars were developed using germplasm from the Quaker Oat International Nursery, a long-term collaborative program of open exchange of oats superior germplasm among breeders in a global scale.

Resumo em Inglês:

Abstract BRS A705 is an early-maturing cultivar developed by Embrapa, recommended for irrigated cultivation. The plants have high tillering and moderate resistance to the main diseases. This cultivar has short stature, which confers a greater tolerance to lodging. It presents high yield and long and fine grains of excellent quality.