Resumo em Inglês:

Abstract Microsatellites have been widely used to genotype individuals and to address a myriad of biological questions in many research fields for decades. However, when implementing a microsatellite marker analysis routine from scratch, various problems can arise throughout the process from DNA extraction to allele scoring, including inputting errors in the database, decreasing the reliability of results and having profound negative impacts on the derived decisions. Therefore, correctly assigning a genotype to a sample is crucial and dependent on acquiring knowledge of the technique steps, such as the chemistry of reactions, software, and data curation. This study tested two previously constructed simple sequence repeat (SSR) sets containing ten primer pairs each (ten-plex) in 1142 maize genotypes. Here, we describe the challenges faced when implementing this microsatellite-based genotyping protocol in our laboratory and possible ways to overcome them, hopefully aiding other novice research teams in this field.

Resumo em Inglês:

Abstract We investigated the genetic control of the three yield components in cowpea: number of grains per pod, pod length and grain size, in a biparental cross. Genetic parameters were estimated in generations of a cross between two contrasting genitors, using a randomized complete block design with three replications. Narrow-sense heritability estimates varied from 27% to 67%, suggesting that genetic gains can be achieved with selection. Pod length and grain size had the highest heritability values and genetic gains. The number of grains per pod is highly affected by the environment. Dominance was detected for all traits, mainly for pod length. However, additive gene effects accounted for more than 68% of the variation in all traits, which are controlled by at least 10 genes. It is possible to improve the evaluated traits via conventional breeding approaches, although large population sizes will be required in breeding stages.

Resumo em Inglês:

Abstract Identification of early haploids is necessary to increase the efficiency of the double haploid production. The objectives were to determine the effectiveness of early selection of haploid seedling and to investigate the haploid inducers and donor tropical supersweet corn interactions, based on stomatal guard cell length. Two haploid inducers, three supersweet corn populations and its six combinations of F1's diploid and haploid, classified based on the expression of the R1-navajo gene and by the colors of the first leaf sheath in seedlings at the V2 stage, were used. From each seedling of the treatments, external epidermal impressions were taken to measure the stomatal guard cell length. F1 haploids showed a 32.7% to 38.2% reduction in guard cell length compared to F1 diploids. The parents contributed differently to reduce or increase guard cell length in the F1's combinations, but without specific interactions between parents.

Resumo em Inglês:

Abstract This study aimed to select recombinant lines and explore phenotypic and genotypic correlations using BLUP. It was conducted in Capão do Leão/RS during two years, in an incomplete block design with intercalary controls, with four replications. 131 and 128 RILs were tested in the F6 in the F7 generations, respectively. Plant height; days to flowering; panicle length; number of panicles per plant; number of fertile and sterile spikelets per panicle; one hundred grains weight; yield per plant; broken, chalky, white-belly and red-streaked grains; vitreous whiteness; gelatinization temperature; and apparent amylose content were obtained. According to the study, line F105 is an elite line for improving grain quality, exhibiting high amylose content (27.041%). Canonical (r=0.817), phenotypic (0.541) and genotypic (0.808) correlations inferred that groups of grain quality and agronomic traits were not independent and there was a tendency for the amylose content to be associated with grain yield.

Resumo em Inglês:

Abstract To exploit the genetic potential of cherry tomato, it is crucial to comprehend the inheritance pattern of qualitative and quantitative traits. Six genetic populations created from four crosses between pairs of cherry tomato and purple-fruited tomato genotypes were used to study the genetics of fruit colour and the nature of gene action for quantitative traits in cherry tomatoes. The study indicated purple fruit colour was dominant over red and yellow fruit colour in cherry tomatoes and was conditioned by mongenic dominant gene. Quantitative trait inheritance was governed by non-additive gene action and duplicate epistasis. It is advised to use the modified bulk selection strategy, in which selection is conducted only when homozygosity has been attained for the majority of the heterozygous loci. However, the ideal method for developing cherry tomato hybrids with purple-coloured fruit is to involve at least one purple-fruited parent in the cross.

Resumo em Inglês:

Abstract Identifying a stable high-yielding variety is challenging. This paper reports high-yielding and stable durum wheat candidates identified using AMMI, GGE biplot models, and stability parameters. Twenty-five lines were evaluated in 13 environments in 2018 and 2019 using a triplicate row-column design. AMMI, stability, and GGE biplot analyses were conducted using packages in the R statistical software. AMMI indicated highly significant effects of environments, genotypes, and their interactions on grain yield. The highest proportion of the total sum of squares accounted for by the environment (42.3%), followed by the genotype by environment interaction (26.7%), may suggest the presence of diverse environments grouped into mega-environments. The environments fell into three sectors on the which-won-where view of the biplot and they were grouped into two mega-environments. Genotypes 5 and 15 were the highest yielding and most stable among all and are recommended as candidate varieties for the midlands to highlands of Ethiopia.

Resumo em Inglês:

Abstract Families of 38 month-old Calycophyllum spruceanum planted at three locations in the Peruvian Amazon were analyzed for breeding purpose. Significant differences were detected among families, sites and combined sites for the traits trunk diameter (D), height (H), number of nodes (NN), number of branches (NB) and survival rate (SUR), except for NN at site 2 and SUR at site 3 and combined sites. The correlation of the genotype-environment interaction was simple for D, H, NN, and SUR (0.77-0.89). Heritability was generally highest for D, H, NN, and NB (0.12-0.7), and the genotypic coefficient of variation ranged from 8.6-27.4%. Genetic correlations between these traits within and among sites ranged from 0.35-1.0. The selection of 75 trees from different families, within blocks and locations, suggested the possibility of genetic gains (6.1-29.8%) for D, H, NN, and NB, and that the remaining effective population size can be exploited in future selection cycles.

Resumo em Inglês:

Abstract Hymenaea stigonocarpa (“jatobá-do-cerrado”) is a fruit species native to the Brazilian Cerrado indicated as a priority for research and sustainable exploitation. The present study aimed to characterize the accessions and evaluate the magnitude and distribution of the genetic variability of an in vivo germplasm collection of this species. The experimental material consisted of 336 accessions, from 119 maternal progenies, from 24 subpopulations, sampled over a wide area in the Cerrado. The traits plant height, stem diameter, number of branches and number of leaves were evaluated based on 11 measurements, over 28 months. The growth dynamics varied over time, with greater development in the rainy season. There was a significant difference among subpopulations for all growth traits, showing the potential for selection among provenances in a breeding program. The structuring of quantitative genetic differentiation among subpopulations is compatible with the variation expected by genetic drift, with no sign of divergent selection.

Resumo em Inglês:

Abstract In Brazil, lima bean is mainly grown in the Northeast region, where it is widely consumed and is of major economic importance. We evaluated different Phaseolus lunatus accessions from the Northeast of Brazil using agromorphological markers and CMA/DAPI fluorochrome banding techniques. All the accessions showed CMA+ blocks of pericentromeric constitutive heterochromatin (CH). At least one pair of CMA++ terminal marks corresponds to the nucleolus organizer region (NORs). Characterization of the seeds suggests that the two Andean and Mesoamerican Phaseolus cultigroups are represented in the Brazilian germplasm analyzed. Most of them belong to the "Big Lima" group. Characterization studies of lima bean germplasm are important for increasing knowledge of the diversity and variability of the species and for generating useful information for breeding and conservation of this economically important legume.

Resumo em Inglês:

Abstract Soybean (Glycine max L.) is a major global crop. Genetic modification of this crop can contribute to enhance yields, reduce pesticide use, and facilitate sustainability, but there is a need for locally adapted genetically modified varieties. Glyphosate tolerant soybean developed under an agbiogeneric model is an attractive prospect as the technology is now mostly in the public domain. This research evaluates the potential for transformation of three soybean varieties (BR1, BR2, and FNS) and an established variety (SK7). The study investigates the interaction between these genotypes and two A. tumefaciens strains, establishes a selection protocol using glyphosate, compares two explant types and evaluates a bacterial removal protocol. Our findings highlight the importance of plant genotype and bacterial strain specificity in the transformation process, with variety BR1 consistently showing the best performance. While challenges remain, this study advances in the development of glyphosate-tolerant soybean varieties as agbiogenerics.

Resumo em Inglês:

Abstract The objective of this study was to introduce new cultivars of Capsicum frutescens L. (pepper) with resistance to anthracnose. 'UNEMAT Pedro' is characterized by its red fruits, while 'UNEMAT Malagueta Pantaneira' is hybrid with orange‒red fruits. Both cultivars exhibit a semi-perennial growth cycle, a pungent fruit flavour, and high productivity.

Resumo em Inglês:

Abstract Hanyou 3015 is a new Indica hybrid of water-saving and drought-resistance rice (WDR), combining rapid maturation and high yield potential. Whole genome sequencing results show that Hanyou 3015 carries many superior alleles that could explain its drought tolerance, high water use efficiency, rapid maturation, and wide adaptability.

Resumo em Inglês:

Abstract Deep purple is an open-pollinated variety, well adapted to tropical conditions, developed to induce maternal haploids in maize. The founders were W23, Stock6, and an experimental tropical maize population. The inducer population inherits the dominant the R1-nj marker, and the expected real haploid induction rate is 3%.