Eduardo Alves da Silva

Barley ( Hordeum vulgare L.) has a strategic role in global agriculture due to its use in food, feed, and brewing industries and its adaptability to diverse environments. This study evaluated the effect of harvest timing on seed quality in two commercial cultivars (ABI Rubi and ABI Valente), focusing on physical integrity, physiological performance, sanitary status, and chemical composition. Field experiments were conducted in Brazil, under three harvest management conditions: (1) physiological maturity, (2) physiological maturity with desiccation, and (3) full maturity (13% grain moisture, Zadoks stage 92). The variables analyzed included yield, germination, vigor (accelerated aging and electrical conductivity), pathogen incidence, and starch and protein content. Seed health was not influenced by harvest management. However, desiccation at physiological maturity and full maturity increased starch (51%–54%) and protein contents (10.3%–11.5%), with responses influenced by genotype‐environment interactions. Although full maturity provided satisfactory quality, it involved greater risks under adverse weather. Harvesting at physiological maturity without desiccation reduced germination in climatically unfavorable years, whereas desiccation at this stage proved to be the most effective strategy for preserving barley seed quality under unstable climatic conditions. These results support the definition of harvest strategies aimed at maintaining seed quality for malt production.

The quest to restore the capacity for botanical seed production in garlic is fundamental for increasing genetic variability and facilitating the selection of superior genotypes. Thus, this study aimed to evaluate the effects of exogenous plant growth regulators on the flowering capacity and production of botanical seeds in garlic. The experiment was conducted in the Universidade Federal de Lavras (UFLA), Brazil, in a randomized complete block design with four replications in a 7×3 factorial design. Each experimental unit consisted of three 5 dm³ pots, maintained under open-field conditions. Six doses of different plant growth regulators were evaluated: GA3 and PBZ (3.5 mg/L GA3; 9 mg/L GA3; 18 mg/L GA3; 480 mg/L PBZ; 3,600 mg/L PBZ; 7,200 mg/L PBZ) in addition to a control treatment (water), applied during the pre-anthesis, anthesis, and post-anthesis stages. Traits related to flowering and seed production were evaluated. The results implicate that the application of plant growth regulators in the garlic crop modified the reproductive physiology of the plants, influencing the potential for flowering and seed production. The doses of PBZ (7,200 mg/L) and GA3 (18 mg/L), applied at pre-anthesis, increased the potential of botanical seed production. The results indicate that higher doses of the evaluated plant growth regulators can improve flowering and stimulate seed production in garlic.

Wheat blast caused by Magnaporthe oryzae Triticum (MoT) threatens wheat production, affecting plants at various growth stages. Resistant cultivars, linked to the 2N ^V S chromosomal translocation, offer potential control strategies, though questions persist about their effectiveness against diverse MoT isolates. This study aimed to (a) characterise and compare the virulence of 77 MoT isolates from wheat cultivated in Brazil based on the reaction of a set of 11 wheat cultivars to the pathogen infection; (b) characterise and compare the wheat genotypes based on their response to infection by MoT isolates, and correlate the presence of the 2N ^V S translocation; and (c) identify effector genes and their variations among isolates through whole‐genome sequencing of a subgroup of 25 representative Brazilian MoT isolates and analyse the effectors concerning the isolates' severity. A randomised design measured blast severity on detached wheat heads 7 days post‐inoculation. Significant genotype‐by‐isolate interactions were observed, revealing that some isolates caused severe symptoms even in cultivars carrying 2N ^V S. Resistance conferred by 2N ^V S depended on the genetic background of the cultivars. Cultivar BRS 229, lacking 2N ^V S, exhibited great resistance, comparable to Jagger and Santa Fe. Effector gene analysis identified 47 candidate genes, seven of which showed variations correlating with isolate aggressiveness. The findings highlight the complex interaction between MoT virulence and wheat genotypes, underscoring the need to broaden resistance strategies. These results provide essential insights into managing wheat blast, emphasising the importance of integrating genetic diversity in resistance breeding programmes, and the sequencing of 25 complete MoT genomes in this study provides a critical genomic foundation for future research in this important pathogen.

Utilizing selection indices is an effective strategy for the simultaneous evaluation of multiple traits in kale breeding programs. This approach allows for the selection of kale genotypes that exhibit enhanced productivity and adaptability by combining desirable attributes for the crop. In this study, we employed a mixed model approach in combination with various selection indices to estimate selection gains and recommend the most suitable index for kale breeding. The experiment was conducted at the Center of Development and Technology Transfer, Federal University of Lavras, Ijaci, MG. Thirty-four experimental genotypes were assessed in a randomized block design with three replicates, featuring four plants per plot. We evaluated several traits, including total leaf yield, number of leaves, average leaf mass, number of sprouts and chlorophyll content. Data analysis was performed at both the plot average level and the average quantity of the five harvests. Statistical analysis of mixed models confirmed the presence of genetic variability among kale genotypes. We examined the Smith and Hazel, Mulamba and Mock, Z-index, and FAI-BLUP indices. Smith and Hazel, Mulamba and Mock, as well as Z-index, were found unsuitable for leafy kale selection in breeding programs. The FAI-BLUP index demonstrated superior performance, aligning with the specific objectives of the kale breeding program and offering desirable gains. Therefore, we recommend the use of the FAI-BLUP index in kale breeding programs.

Environmental conditions significantly impact the performance of sweet potato genotypes, necessitating the study of genotype x environment (GE) interactions to select genotypes adaptable to varying cultivation conditions. This study aimed to assess GE interactions in sweet potatoes for animal feed and identify high-performance genotypes suitable for different seasons. We conducted two tests during the Brazilian winter of 2019 and summer of 2020. Employing a partially balanced triple lattice experimental design with 100 treatments (92 sweet potato genotypes and eight controls) and three replications, we measured vine green matter yield (VGMY), percentage vine dry matter (PVDM), vine dry matter yield (VDMY), percentage of root dry matter (PRDM), and roots dry matter yield (RDMY). We ranked genotypes, highlighting the best performers for individual and combined seasons. Significant differences in VGMY, PRDM, and RDMY were observed for GE interaction. VGMY, VDMY, and PRDM favored the summer season, while PVDM and RDMY performed better in the winter season. Genotypes 2018-31-713, 2018-72-1438, 2018-31-666, 2018-12-252, 2018-19-461, 2018-19-389, 2018-38-946, 2018-31-689, and 2018-37-864 proved most suitable for VGMY and VDMY across growing seasons. Genotypes 2018-28-514, 2018-15-268, and 2018-19-443 demonstrated potential in percentage vine dry matter. Genotypes 2018-31-666, 2018-72-1438, and 2018-15-277 are recommended for PRDM in both seasons. Genotypes 2018-19-464, 2018-28-556, 2018-55-1154, 2018-28-543, 2018-53-1038, 2018-72-1432, and 2018-19-443 exhibited greater potential for RDMY, making them ideal for animal feed in both growing seasons.

The objective of this work was to estimate the genetic parameters and correlations of characteristics related to production and color in kale and to select the best genotypes based on REML/BLUP estimates. The experiment was carried out in a completely randomized block design, with three replicates. The treatments consisted of 34 experimental kale clones. The parameters evaluated were: total leaf yield (TLY), number of commercial leaves (NCL), average leaf mass (ALM), number of shoots (NS), chlorophyll content (CC), and colorimetric patterns of luminosity (L), chroma (C), and hue (h) of the leaves. Genetic parameters, genotypic and phenotypic correlations, and genetic values were estimated. The kale genotypes UFLA 06, UFLA 14, UFLA 16, UFLA 22, and UFLA 34 have good productive characteristics and intense green color, with high heritability. The characteristics TLY, NCL, ALM, NS, CC, and colorimetric patterns of L and C present high heritability in kale. TLY shows a positive correlation with the NCL and the ALM in kale. The genotypes UFLA 02, UFLA 04, UFLA 13, UFLA 25, UFLA 31, and UFLA 32 stand out for their productive characteristics, but not in high levels of antioxidants. The NCL presents positive correlation with the NS, which does not benefit seed production.

Kale is one of the most widely cultivated leafy vegetables in Brazil, but its breeding genetic is still limited. Therefore, it is crucial to develop research that explores the genetic diversity of the available germplasms, aiming to establish promising crosses in the studied populations. The present study aimed to evaluate the genetic divergence between half-sibling progenies of kale, obtained through recurrent selection, using multivariate methods to select the most promising progenies for forming a recombinant population. The plants obtained from the seeds of 25 pre-selected half-sibling progenies and three commercial cultivars were evaluated as treatment groups. These seeds were produced in 2018 by subjecting the clones of the progenies to recombination, followed by the selection of appropriate seeds from plants with superior agronomic performance. In the present study, plants in each plot were evaluated for twelve quantitative and fifteen qualitative traits. Genetic divergence was studied based on canonical variables to obtain quantitative data. The UPGMA method was applied to the quantitative, qualitative, and combined data, and Mahalanobis genetic distance was adopted. The first three canonical variables explained 73.75% of the total cumulative variation compared to the commercial cultivars and 55.29% when considering the half-sibling progenies exclusively. The half-sibling progenies P1, P2, P3, P4, P5, P9, P11, P15, P16, P18, P20, P22, P23, P24, and P25 were the most divergent and should, therefore, be prioritized when composing the recombinant population for the third cycle of recurrent selection because, in addition to genetic variation, these progenies also present characteristics of interest to the kale genetic breeding program. The commercial cultivars exhibited the most divergent genotypes and should, therefore, be included in the next recombination cycle.

The objective of this work was to select sweet potato (Ipomoea batatas) genotypes with leaves with potential to be used for human consumption. Twenty-six experimental genotypes and four commercial cultivars were tested in a randomized complete block design with three replicates and ten plants per plot. The trial was carried out in the municipality of Lavras, in the state of Minas Gerais, Brazil. Leaf shape and lobe, aerial-part yield, edible-leaf yield, edible-leaf percentage, edible-leaf dry mass, and latex production, as well as leaf total chlorophyll, pH, soluble solids contents, titratable acidity, total phenolic compounds, and anthocyanin contents, were evaluated. Roots were characterized as to their pulp and peel colors. Fifteen genotypes presented the highest aerial-part (29.6 to 51.8 Mg ha^-1) and edible leaf (7.8 to 12.7 Mg ha^-1) yields. In the biochemical analysis, high contents of chlorophyll, total phenolics, and anthocyanins were observed. In addition, pH, soluble solids, and leaf titratable acidity did not differ significantly among the evaluated genotypes. Leaves of ten genotypes are recommended for human consumption.

Alface ( Lactuca sativa L.) is a leafy vegetable worldwide consumed. It is found in its constitution vitamins and minerals, as well as bioactive compounds, such as phenolic compounds, flavonoids and anthocyanins. Since anthocyanins are responsible for the red color of the leaves and in the body prevents the appearance of non-communicable chronic diseases by the fight against free radicals. The lettuce for being present in the diet of the population becomes a promising plant for biofortification with the selection of plants with high levels of anthocyanins. The objective of the present work was to study the quantitative distribution of anthocyanin in leaves of lettuce plants of a segregating F2 population obtained from the initial crossing between two color contrasting parents (green and red).. The color, anthocyanin and flavonoid contents, as well as color correlation with anthocyanin content and the heritability of these characteristics. It was concluded that the anthocyanin content in leaves of lettuce is controlled by more than one gene with partial dominance of the genes that confer higher levels. Intense red coloration can be used as an alternative in lettuce breeding programs to identify superior lettuce genotypes with high anthocyanin content. Transgressive segregation as well as the higher heritability values observed in the studied traits will allow selecting in segregating generations, superior genotypes in accordance with the proposed objectives.

The objective of this work was to estimate the optimal number of harvests for the reliable selection of zucchini (Cucurbita pepo) hybrids through the repeatability coefficient. The experimental design was randomized complete blocks with 33 treatments (31 experimental hybrids and 2 commercial ones) and four replicates, with six plants per plot. Fifteen harvests were carried out. Seven morphoagronomic fruit characteristics were evaluated, and repeatability coefficients were estimated using four statistical methods. The repeatability coefficients ranged from low to moderate, regardless of the studied characteristic. For a high-precision selection (R2≥90%), a high number of evaluated harvests was required, especially for traits related to fruit yield, as follows: 30 to 54 harvests for selection based on total yield; and 43 to 83 harvests for commercial yield, which varied according to the statistical estimation method. The principal component analysis based on the covariance matrix required the least number of harvests for a satisfactory selection precision. Fifteen harvests are sufficient for a satisfactory selection of all evaluated characteristics, with a precision above 70%.