The study of the genetic and phenotypic variability of the populations of Caryocar brasiliense Camb. assists in strategies for conservation and breeding of the specie. The objective of this work was to characterize the genetic diversity through the physical characteristics of pequi fruits of two populations through uni and multivariate analysis, as well as the implications in their domestication and breeding. Fruits were harvested from 20 mother trees (ten fruits per mother tree) from two populations in the state of Minas Gerais (Curvelo and São Gonçalo do Rio Preto Municipalities) during the years 2010, 2011 and 2012. The data were submitted to analysis of variance using a hierarchical classification model. An analysis of clusters and main components was used for studying the divergences. The effects of the populations were not significant for all the characters analyzed in isolation. The gathering of pequi mother trees shown by multivariate analysis did not correspond to the grouping established by the populations. Selection for breeding and/or preservation purposes should concentrate efforts on fewer populations with larger numbers of mother trees per population. Selection of mother trees with higher fruits and thicker pulp fruits among them, even by visual evaluations only, is recommend in sampling mother trees for breeding purposes.
Resumo -Parâmetros genéticos estimados por meio de delineamentos genético-estatísticos considerando-se efeitos de populações e progênies são inexistentes para o pequizeiro (Caryocar brasiliense Camb.). O objetivo deste trabalho foi estimar parâmetros genéticos e avaliar a eficiência da seleção baseada em caracteres de crescimento em estádio precoce nesta espécie. O experimento foi instalado em janeiro de 2005, utilizando-se mudas de 31 matrizes originadas de duas procedências, em um delineamento em blocos ao acaso com seis repetições e cinco plantas por parcela, no município de Carbonita, MG. Nos anos de 2005 a 2008 avaliaram-se os caracteres: altura de planta (2005; 2006; 2007 e 2008), diâmetro do caule ao nível do solo (2006; 2007; 2008) e diâmetro da copa (2008). As estimativas da herdabilidade no sentido restrito em nível de indivíduo variaram de 0,15 a 0,50. As correlações genéticas e fenotípicas entre os caracteres nos diferentes anos foram positivas e em geral altamente significativas. Estimativas da eficiência de seleção obtidas pela expressão de Hamblin e Zimmermann variaram de médias a altas para todos os caracteres. Concluiu-se que, na hipótese de correlação significativa entre os caracteres avaliados e a produção de frutos, a seleção para produção de frutos, baseada em caracteres de crescimento, pode ser iniciada em estádio precoce. Palavras-chave -Caryocar brasiliense. Progênies. Eficiência de seleção. Melhoramento genético.Abstract -Genetic parameters estimated through statistical-genetic designs considering population and progeny effects are lacking for the pequi tree (Caryocar brasiliense Camb.). The aim of this study was to estimate genetic parameters and evaluate the efficiency of selection based on growth traits in the early stages. The experiment was carried out in Carbonita, Minas Gerais, Brazil, on January of 2005, using a randomized block design with 31 progenies, six replications and five plants per plot. From 2005 to 2008 the following traits were evaluated: plant height (in 2005; 2006; 2007 and 2008), stem diameter at ground level (in 2006; 2007; 2008) and crown diameter (in 2008). Estimates for narrow-sense heritability at the individual level varied from 0.15 to 0.50. The genetic and phenotypic correlations between characteristics in the different years were positive and generally highly significant. Estimates of the selection efficiency, obtained using the Hamblin and Zimmermann Expression, ranged from medium to high for all traits. It was concluded that under the premise of a significant correlation between these traits and fruit production, selection for fruit production based on growth traits could be started at an early stage.
This study describes and illustrates Cattleya mireileiana (Orchidaceae: Laeliinae), a new species endemic to the Southern Espinhaço Complex near Diamantina, Minas Gerais State, Brazil, where it was found in a few isolated rocky outcrops, sharing habitat with Cattleya rupestres. It is close to three other species: Cattleya bradei, C. briegeri, and C. cruziana. However, the new species differs in the number of nodes present in the pseudobulb components, the size of the diameter, the scent of the flowers and the time of flowering. In addition, its flowers have two unique chromatic characteristics that distinguish it from all other species with yellow flowers in the Parviflorae series: the color of the carinae and the whitish area at the base of the petals and sepals. We provide a detailed morphological description, a distribution map, in situ photographs, and compare it with similar species. We assessed its state of conservation as data deficient (DD), as the only know population consists of at least 150 mature individuals and is outside of an environmentally protected area.
Este trabalho tem o objetivo de apresentar os limites e possibilidades da perspectiva curricular Situação de Estudo (SE) em duas escolas públicas, durante as feiras de Ciências que ocorreram na Semana da Educação para a Vida em 2017 na cidade de Diamantina-MG. Para compreender as potencialidades e limitações das SEs, participaram da pesquisa os licenciandos envolvidos no PIBID Biologia da UFVJM e dois professores supervisores do PIBID (um em cada escola). A coleta de dados consistiu na análise dos diários de campo da coordenadora de área e dos pibidianos e na realização de um grupo focal com os sujeitos participantes, cujas falas foram transcritas e analisadas pela Análise Textual Discursiva (ATD). Por meio do processo de categorização da ATD, os resultados foram evidenciados em cinco categorias pré-estabelecidas: 1) Surgimento dos temas; 2) Interdisciplinaridade; 3) Diálogo/Interação; 4) Organização da feira; e 5) Limites e possibilidades da SE. Os resultados indicam que a categoria “interação/diálogo”, entre os sujeitos envolvidos na preparação da feira, teve papel central no sucesso da SE. Ela parece ser um eixo fundamental sobre o qual se articulam as demais categorias. Por outro lado, uma limitação evidenciada foi a falta de diálogo entre os sujeitos, dificultando a concretização de uma SE.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.