RESUMO: O estudo das relações genotípicas entre índices de tolerância à seca e caracteres agronômicos de interesse no melhoramento de trigo é útil para traçar estratégias de seleção. Objetivou-se com este trabalho investigar as relações de causa e efeito entre características agronômicas e índices de tolerância à seca via análise de correlações canônicas. Dois ensaios (controle e estresse) foram conduzidos no inverno de 2020 em Viçosa, MG, Brasil. Foram avaliados os caracteres (dias para o espigamento, altura da planta, massa e número de grãos por espiga, massa de cem grãos e rendimento de grãos). Os dados de produtividade dos ensaios de controle e estresse foram utilizados para construir cinco índices de tolerância à seca. Os dados foram submetidos à análise de modelos mistos para estimação dos parâmetros genéticos e predição dos valores genotípicos (REML/BLUP), em seguida, os valores genotípicos foram utilizados para calcular os coeficientes de correlação entre os caracteres. Dois grupos de caracteres foram estabelecidos para o estudo das correlações canônicas, sendo o primeiro grupo constituído pelas variáveis agronômicas e o segundo pelos índices de tolerância à seca. Houve efeito significativo de genótipo para todas as características avaliadas. Os pares canônicos foram significativos, o que indicou a existência de dependência entre os grupos. O caráter dias para o espigamento pode ser utilizado na seleção indireta de genótipos de trigo para tolerância à seca. RESUMO Objetivouse Objetivou se canônicas 202 Viçosa MG Brasil planta espiga grãos. . grãos) REML/BLUP, REMLBLUP REML/BLUP , REML BLUP (REML/BLUP) seguida avaliadas significativos 20 (REML/BLUP 2

ABSTRACT: The study of genotypic relationships between drought tolerance indices and agronomic traits of interest in wheat breeding is useful for designing selection strategies. The objective of this research was to investigate the cause-and-effect relationships between agronomic traits and drought tolerance indices through the analysis of canonical correlations. Two trials (control and stress) were conducted in winter 2020 in Viçosa, MG, Brazil. The traits evaluated were: (days for heading, plant height, mass and number of grains per spike, mass of one hundred grains, and grain yield). Grain yield data from the control and stress conditions were used to construct five drought tolerance indices. The data were subjected to mixed model analysis for estimation of genetic parameters and prediction of genotypic values (REML/BLUP), and then the genotypic values were used to calculate the correlation coefficients between the traits. Two groups of traits were established for the study of canonical correlations, the first group consisting of agronomic traits and the second by drought tolerance indices. There was a significant genotype effect for all evaluated traits. The canonical pairs were significant, which indicated the existence of dependence between the groups. Days to heading trait can be used in the indirect selection of wheat genotypes for drought tolerance. ABSTRACT strategies causeandeffect cause correlations 202 Viçosa MG Brazil days height spike yield. . yield) REML/BLUP, REMLBLUP REML/BLUP , REML BLUP (REML/BLUP) 20 (REML/BLUP 2

Abstract In many cases, traditional analysis of breeding trials based on analysis of variance (ANOVA) do not allow a suitable genetic evaluation. Alternatively, mixed model-based approaches create the possibility of dealing with unbalanced data and modeling spatial trends. The aims of this study were to compare the goodness-of-fit of the model and the genotype ranking through different residual modeling approaches and to select the best performing tropical wheat genotypes based on the best-fitting model. A panel of tropical wheat genotypes was evaluated in three field trials conducted between 2020 and 2021 for grain yield. Linear mixed model analyses were used on the data to estimate the genetic parameters and to predict the genotypic values in analyses of single- and multi-environment trials. Accounting for spatial trends in the analyses of single- and multi-environment trials provides better outcomes than the compound symmetry model does. cases ANOVA (ANOVA evaluation Alternatively modelbased goodnessoffit goodness fit bestfitting fitting 202 yield single multienvironment multi environment does 20 2

RESUMO: Estresses abióticos como calor, seca e salinidade afetam o desenvolvimento da cultura do trigo e dificulta a sua expansão para a região central do Brasil. A identificação de genótipos tolerantes a estas condições são importantes para o melhoramento genético da cultura. Logo, objetivou-se avaliar o impacto de diferentes estresses abióticos sobre parâmetros de germinação e do desenvolvimento de plântulas de trigo via análise multi-trait. Estresses térmico por calor, seca e salinidade foram induzidos em sementes de 23 genótipos de trigo. Foram avaliados a germinação das sementes, comprimento e massa seca da plântula. Foram aplicados sobre os dados, modelo de adaptabilidade e estabilidade e índice de seleção multi-trait. Os ambientes de estresse abiótico por seca e salinidade afetaram negativamente o desenvolvimento das plântulas dos 23 genótipos avaliados. Contudo, os genótipos VI 14055, ORS Madre Pérola e BRS 404 combinam os melhores resultados de adaptabilidade e estabilidade e foram selecionados pelo MGIDI. Por meio disso, estes genótipos são potencias para serem recomendados às regiões em que se ocorre estes tipos de estresses abióticos. RESUMO calor Brasil Logo objetivouse objetivou multitrait. multitrait multi trait. trait multi-trait 2 plântula dados Contudo 14055 40 MGIDI disso 1405 4 140 14 1

ABSTRACT: Abiotic stresses, such as heat, drought and salinity, affect the development of wheat crop and hinder its expansion to the central region of Brazil. The identification of genotypes tolerant to these conditions is important for improving yield performance. The present research evaluated the impact of different abiotic stresses on germination and seedling development and selected wheat genotypes tolerant to these stresses, using multi-trait analysis. Heat, drought and salinity stresses were induced in seeds of 23 wheat genotypes. Seed germination, seedling length and dry mass were evaluated. An adaptability and stability model and a multi-trait selection index were applied to the data. Drought and salinity negatively affected the development of seedlings of the 23 evaluated genotypes. However, the VI 14055, ORS Madre Pérola and BRS 404 genotypes conferred the best adaptability and stability results and were selected by the MGIDI, which revealed that great performance can be achieved in regions with potential for abiotic stress, in the early stages of development. ABSTRACT heat Brazil multitrait multi trait analysis Heat 2 data However 14055 40 MGIDI stress 1405 4 140 14 1

RESUMO Tephrosia egrégia Sandwith é uma espécie que se desenvolve em alguns Estados do Nordeste. Sua propagação é realizada por meio de sementes, sendo uma espécie potencial para restauração. Os objetivos foram caracterizar o desenvolvimento pós-seminal e avaliar a germinação das sementes sob diferentes temperaturas e sob estresse hídrico e salino. Testes de germinação foram conduzidos a 20, 25, 30 e 20-30 °C e sob concentrações de PEG6000 e NaCl (-0.2, -0.4, -0.6 e -0.8 MPa). O teste de germinação deve ser conduzido em rolo de papel sob temperatura constante de 25 ºC durante 14 dias. A germinação das sementes é reduzida a partir do potencial hídrico de -0.2 MPa, sendo a espécie sensível ao estresse hídrico. Sob estresse salino, a redução mais acentuada na germinação, a partir de -0.4 MPa, sendo isso um indicativo de uma certa tolerância à salinidade. Nordeste restauração pósseminal pós seminal salino 20 3 2030 20-3 C PEG PEG600 0.2, 02 0 2 (-0.2 0.4, 04 4 0.6 06 6 -0. 0.8 08 8 MPa. MPa . MPa) 1 dias 0.2 0.4 salinidade 203 20- PEG60 (-0. 0. -0 PEG6 (-0 - (- (

ABSTRACT Tephrosia egregia Sandwith is a species that develops in some States of the Northeast region of Brazil. It is propagated by seeds and has considerable potential for restoration. Thus, studies related to seed germination are important for the species. The aims were to characterize the post-seminal development and evaluate the germination response of the seeds under different temperatures and water stress and salt stress. Germination tests were performed at 20, 25, 30 and 20-30 °C and under PEG 6000 and NaCl concentrations (-0.2, -0.4, -0.6 and -0.8 MPa). The germination test should be conducted in a paper roll at 25 ºC for 14 days. Seed germination declines from the water potential of -0.2 MPa on; the species is sensitive to water stress. Under salt stress, there is more accentuated decline in germination as from -0.4 MPa, and this is an indication have a certain tolerance to salinity. Brazil restoration Thus postseminal post seminal 20 3 2030 20-3 C 600 0.2, 02 0 2 (-0.2 0.4, 04 4 0.6 06 6 -0. 0.8 08 8 MPa. . MPa) 1 days 0.2 on 0.4 salinity 203 20- 60 (-0. 0. -0 (-0 - (- (

ABSTRACT The immediate need for the increase in wheat production to meet the future world demand, associated with the occurrence of drastic climatic events, such as drought, makes it necessary to develop drought-resilient genotypes. The aims of this work were to evaluate the use of drought-tolerance indices for the selection of wheat genotypes, to compare the genetic gains in grain yield using different selection strategies by means of a multi-trait index, and to select superior drought-tolerant wheat genotypes. The total of 31 tropical wheat lines was evaluated in two experiments. Five agronomic traits were accessed. The grain yield data from the stress and nonstress experiments were used to obtain five drought-tolerance indices. The data were subjected to mixed model analysis, and four selection scenarios were designed. There was a significant effect of genotype for all traits. The inclusion of drought-tolerance indices in the selection index provided superior genetic gains in drought condition. Seven lines were selected due the high frequency of favorable alleles for drought-tolerance and other important agronomic traits. Drought-tolerance indices are appropriate for characterizing the response of wheat genotypes to drought-stress. The inclusion of drought-tolerance indices along with agronomic traits in multi-trait selection strategies provides for superior gains in grain yield compared to the non-inclusion of the indices. demand events droughtresilient resilient droughttolerance tolerance multitrait multi trait droughttolerant tolerant 3 accessed analysis designed condition Droughttolerance Drought droughtstress. droughtstress stress. drought-stress noninclusion non

ABSTRACT: Successive cycles of water absorption and loss favor weathering deterioration, one of the main factors that affect the quality of soybean seeds. This study evaluated the physiological, physical, and morpho-anatomical changes in soybean seeds under weathering deterioration at the pre-harvest phase. Six soybean cultivars (BMX Apolo, DM 6563, NS 5959, NA 5909, BMX Potência, and TMG 1175) were produced in a greenhouse and underwent weathering deterioration through a rainfall simulation system, applying 0, 60, 120, and 180 mm of precipitation at pre-harvest phase. Each rainfall level was divided into two applications at an interval of 72 h: 60 mm (30 + 30), 120 mm (60 + 60), and 180 mm (90 + 90). After harvest, the seeds were evaluated for germination, vigor, physical and morpho-anatomical properties. Weathering deterioration induced by simulated rainfall at the pre-harvest phase contributes to the reduction in soybean seed germination and vigor and is conditioned by the soybean genotype. The increase in intensity of simulated rainfall led to a more significant weathering damage in seeds, as evidenced by the X-ray and tetrazolium test. Cultivars DM 6563 and BMX Potência were more susceptible, while NA 5909 was less susceptible to weathering deterioration (especially at the highest level; 120 mm and 180 mm). Anatomical changes caused by weathering deterioration lead to cell compaction and rupture, mainly in the cell layers of the hourglass and parenchyma, forming intracellular spaces. The presence of weathering damage caused a reduction in physiological soybean seed quality.

Resumo Orchidaceae é a maior família de plantas vasculares, e constitui-se num grupo sob intensa ameaça devido à ação antrópica. Cattleya caulescens e C. endsfeldzii são espécies rupícolas endêmicas de Minas Gerais, Brasil, e figuram em listas vermelhas de espécies ameaçadas de âmbito estadual e nacional. Sendo assim, foram conduzidos estudos morfoanatômicos com o objetivo de incrementar os conhecimentos desses táxons, tendo em vista o potencial que esses estudos representam no manejo de espécies. Cattleya caulescens e C. endsfeldzii apresentam fortes similaridades morfoanatômicas, o que apoia estudos anteriores, que incluem ambas numa mesma seção do gênero. Diversas características anatômicas aqui descritas (epiderme unisseriada, folha hipoestomática, grandes campos de pontuações primárias no parênquima clorofiliano e a anatomia da raiz) são comuns a várias outras espécies de Orchidaceae. Os caracteres xeromórficos observados estão relacionados às condições edafoclimáticas, já que ocorrem em substrato rochoso, em constante exposição aos raios solares e restrição hídrica severa durante a maior parte do ano. Este trabalho contribui para se ampliar o conhecimento do gênero Cattleya e auxiliar na delimitação taxonômica destas espécies ameaçadas, ocorrentes em áreas de intensa atividade antrópica.

Abstract Orchidaceae is the largest family of vascular plants and is a group under intense threat due to anthropic activities. Cattleya caulescens and C. endsfeldzii are endemic rupiculous species of Minas Gerais state, Brazil, and listed on Red Lists of endangered species at state and national levels. We conducted morphoanatomical studies with the vegetative organs of the two species, with the objective of increasing knowledge of these taxa, considering the potential that these studies represent in the management of species. Cattleya caulescens and C. endsfeldzii show strong morphoanatomical similarities, which corroborates with previous studies that include both species in the same section of the genus. Many anatomical features described here (presence of single-layered epidermis, stomata only on the abaxial side of the leaf, large primary pit fields in the chlorophyll parenchyma and root anatomy) are common to several other species of Orchidaceae. The xeromorphic features observed in C. caulescens and C. endsfeldzii are related to edaphoclimatic conditions, since they grow on rocky substrate, in constant exposure to solar light and severe water restriction during most of the year. This work contributes to increase the knowledge about Cattleya genus and to support in the taxonomic delimitation of these endangered species occurring in areas of intense antropic activity.

Resumo Coléteres são estruturas secretoras que produzem uma substância pegajosa, constituída por uma mistura de mucilagens, proteínas, terpenos, substâncias pécticas e até alcaloides, que lubrifica e protege o meristema apical. Vários tipos de coléteres têm sido descritos e apresentam valor taxonômico em muitas famílias botânicas. Em Myrtaceae, a descrição de coléteres é recente apresentando três novos tipos morfológicos (cônico, euriforme e petalóide) que diferem dos já descritos para outras eudicotiledôneas. Neste trabalho, são descritos os tipos morfológicos de coléteres em seis espécies de três gêneros pertencentes à tribo Myrteae da subfamília Myrtoideae do Cerrado brasileiro. As amostras foram fixadas para microscopia de luz e eletrônica de varredura. Testes histoquímicos foram realizados em material fresco e em incluído em metacrilato. Foram observados coléteres cônico e euriforme, que não diferiram nem morfoanatomicamente nem quanto à natureza de secreção, daqueles já descritos para espécies de Myrtoideae, o que pode indicar seu uso potencial para fins taxonômicos. Considerando a hipótese de que as linhagens múltiplas de frutos carnosos evoluíram de forma independente na tribo Myrteae, nossos resultados indicam a relevância de estudos adicionais para se reconhecer o padrão de distribuição de coléteres em Myrtaceae.

Abstract Colleters are secretory structures that produce a sticky substance, consisting of a mixture of mucilage, proteins, terpenes, pectic substances and even alkaloids, which lubricates and protects the shoot apical meristem. Several colleter types have been described and have taxonomic value in many botanical families. In Myrtaceae, the colleters description is recent and presents three new morphological types (conic, euryform and petaloid) that differ those already described for other eudicots. In this work, we report the colleters morphological types in six species of three genera belonging to the Myrteae tribe of Myrtoideae from the Brazilian Cerrado. The samples were fixed for light and scanning electron microscopy. Histochemical tests were carried out on the fresh and methacrylate-embedded material. The conic and euryform colleters from Myrtoideae species of the Cerrado did not differ either morphologically nor as to the secretion nature from those described for Myrtoideae species from others biomes, which may indicate their potential use for taxonomic purposes. Considering the hypothesis that the multiple fleshy-fruit lineages have evolved independently in Myrteae tribe, our results indicate the relevance of additional studies in order to recognize the pattern of distribution of colleters in Myrtaceae.