Gleisson de Oliveira Nascimento

A physiological and metabolic database for various species of Amazonian plants is crucial to the species selection and sustainable utilization of their diversity. We hypothesized that understanding the mobilization of Carapa seed reserves and water uptake during germination could provide insights into the physiological behavior and propagation to differentiate species of the same genus. Given this, the mobilization mechanisms of primary reserves, water uptake, and enzymatic activities in seeds of two species of Carapa ( Carapa guianensis and Carapa vasquezii) were investigated. The lipid content was high in both species, with a value of 63.7 ± 4.7% for C. guianensis and 55 ± 1.5% for C. vasquezii. Carapa guianensis showed higher values for the other evaluated reserves. The protein profile highlights a band between 15 and 25 kDa in C. guianensis. As for the enzymatic activities investigated (lipase, amylase, protease, amd acid phosphatase), C. guianensis showed greater activity for most of them, except for acid phosphatase. Overall, the species showed different metabolic strategies and dynamics regarding the water uptake and use of reserves. Our findings indicate that distinct metabolic pathways are employed during the germination and initial seedling growth stages of two Carapa species. This trait can potentially guide the use and conservation of these species.

The main factors governing Hevea brasiliensis germination and seedling establishment remains unclear. We examined the effect of growth regulators Indole 3-Acetic Acid (IAA) and 6-Benzylaminopurine (BAP), and their interactions on germination and the development of mature zygotic embryos (MZE) and protein profile of Hevea brasiliensis seedlings from wild and cultivated (clone PB 250) genotypes. Embryonic axes excised from seeds (wild and clone PB 250) were inoculated in Murashige and Skoog medium (control) and supplemented with IAA (3 µM) and BAP (6 µM) individually and their combination (3 µM IAA + 6 µM BAP). For both genotypes, the mature embryos displayed a high percentage of germination and establishment, and the seedlings were characterized by protein bands ranging from 7 to 30 kDa. Notably, the wild genotype showed proteins in the 14 kDa range, which may be associated with one of the major rubber elongation factors (REF). The wild and clone genotypes presented different behavior and strategies in relation to the protein profile in the presence of different growth regulators. Although the latex biosynthetic pathway and its mechanisms of regulation still remain largely unknown, our results aid in our understanding of the dynamics of proteins in different rubber tree clones in vitro.

Increasing corn grain production without devastating new forest areas is a viable alternative to controlling deforestation. However, increasing plant density in the area may alter plant morphophysiological and productive traits. The objective of this study was to characterize relationships between physiological, morphological and yield traits of corn plants, as well as the cause, effect and relationship of the traits on grain yield. The experiment was carried out in randomized complete block design with four replications. The corn hybrids (2B655PW, AG7088PRO3 and P4285YHR) were grown with row spacing of 40 cm, 60 cm, 80 cm, 95 cm. The evaluated traits physiological were: net photosynthesis (PN), stomatal conductance (Gs), intercellular concentration of CO2 (Ci), leaf transpiration (E), water use efficiency (WUE) and carboxylation efficiency (CE). The morphological were: plant height (PH) and ear insertion height (EIH), stem diameter (SD), and leaf area (LA) and the productive traits were the total number of ear per hectare (NE), number of grains per ear (NGE), grain mass per ear (GME), 100 grain weight (100GW) and grain yield (GY). The characteristics of maize hybrids cultivated in environment with reduced spacing (40cm, 60cm, 80cm, 95cm) of the 2016/2017 crop were investigated through the multicollinearity path analysis. The physiological, morphological and productive traits are considered sources of variation of cause and effect of corn yield in reduced spaced. This traits are essential for observations in maize breeding programs to obtain high yielding varieties in reduced spacing. In conclusion, the physiological (PN, CE, WUE, Ci, Gs), morphological (EIH, SD, LA) and productive (NE, GME) traits provide gains in maize grain yield via indirect selection when the crop is subjected to 40 cm row spacing.

O objetivo deste trabalho foi avaliar as características agronômicas e o desempenho vegetativo e produtivo de 12 variedades crioulas de feijão caupi [Vigna unguiculata (L.) Walp.]. O experimento foi conduzido no período de maio a setembro de 2016, na Fazenda São João, no município de Senador Guiomar – AC. Foram utilizadas 12 variedades crioulas de feijão caupi coletadas nas regiões do Alto Juruá e Alto Purus do Estado do Acre. As variedades crioulas utilizadas foram: Manteigão, Baiano, Costela de Vaca, Mudubim de Rama, Manteiguinha, Quarentão, Ceará, Leite, Fígado de Galinha, Branco de Praia, Arigozinho e Preto de Praia. O experimento foi realizado em blocos casualizados, com 12 tratamentos e quatro repetições. As variedades Leite e Mudubim de Rama destacaram-se com peso de 100 grãos em torno de 35 g. Para o comprimento de vagem, as variedades Costela de Vaca, Mudubim de Rama e Fígado de Galinha obtiveram comprimento de vagens acima de 20 cm. Na avaliação do Índice de grãos as variedades Arigozinho (80,68%), Leite (80,38%), Mudubim de Rama (78,84%) e Ceará (78,20%) se destacaram com as maiores médias. Para produtividade de grãos a média encontrada neste experimento foi de 1301 kg ha-1.

A distribuição espacial das espécies vegetais no topsoil antes da mineração é ferramenta importante e pode fundamentar atividades de recuperação de áreas mineradas. Neste trabalho foi realizada uma análise da distribuição espacial de quatro espécies com abordagem sobre a dinâmica da regeneração em ambientes campestres. Amostras da camada superficial do solo (cinco cm) foram coletadas em agosto de 2011 e março de 2012 em áreas de campos de altitude na região do Planalto de Poços de Caldas, Minas Gerais. As amostras foram dispostas em bandejas e a germinação avaliada em casa de vegetação. Quatro espécies com maior representatividade de germinação foram selecionadas para verificar os padrões de distribuição nos períodos seco e chuvoso por meio da análise de krigagem, e destacou-se a distribuição de A. fastigiatum sugerindo sua potencial indicação para recuperação de áreas após mineração. Palavras-chave: krigagem; áreas degradadas; mapeamento vegetal. SPACE DISTRIBUTION OF SPECIES IN TOPSOIL: IMPLICATIONS TO RECOVERY OF MINING AREAS ABSTRACT: The spatial distribution of plant species in topsoil prior to mining is an important tool and may support recovery activities for mined areas. In this work an analysis of the spatial distribution of four species was carried out to verify its distribution with approach on the dynamics of regeneration in rural environments. Samples of the topsoil (5 cm) were collected in August 2011 and March 2012 in areas of altitude fields in the Planalto region of Poços de Caldas, Minas Gerais. They were arranged in trays and evaluated in a greenhouse. Four species with greater germination representativeness were selected to verify distribution patterns in dry and rainy periods through kriging analysis. Therefore, differences in the spatial distribution of the species were identified, highlighting the distribution of A. fastigiatum suggesting its potential indication for recovery of areas after mining. Keywords: kriging; degraded areas; vegetation mapping.

The viability of propagules during topsoil stockpiling is a limiting factor in ecological restoration projects and little is known about the species distributed in the campos de altitude. This work was carried out to investigate the viability of propagules present in the topsoil under campos de altitude vegetation, stockpiled for up to 12 months after the stripping of areas to be mined. In the south of Minas Gerais, Brazil, between November 2011 and November 2012, four collections of the seed bank were carried out, considering three depths (0 to 10, 90 to 100, and 190 to 200 cm) of the plot of stockpiled topsoil. Using the multivariate analysis, it was verified that the depth factor does not statistically affect the abundance of emerged individuals, while the factor time of stockpiling negatively affects the viability of the seeds. Some species were affected by the stockpiling conditions, only emerging in some collections, while others (Achyrocline satureioides, Ageratum fastigiatum, Baccharis dracunculifolia, Borreria capitata, Echinolaena inflexa and Melinis minutiflora) had individuals emerged in all collection periods. This study points out the need for the return of the topsoil until the fourth month of stocking, under the risk of monodominance, with a prevalence of species more adapted to predominant conditions of campos de altitude.