Divergência genética entre acessos de açaizeiro fundamentada em descritores morfoagronômicos

Abstract

Resumo -Este trabalho teve como objetivo estimar a divergência genética entre acessos de açaizeiro conservados na coleção de germoplasma da Embrapa Amazônia Oriental, em Belém, PA, por meio de descritores morfoagronômicos. A avaliação foi realizada em 87 acessos, com base em 22 caracteres: sete relativos à planta, três à floração, três a frutos e nove à produção de frutos, no período de 1995 a 2001. Foram efetuadas análises univariadas e multivariadas, com estimativas das dissimilaridades obtidas pela distância euclidiana média padronizada, e formação dos agrupamentos obtida pelos métodos UPGMA e Tocher. Os acessos apresentaram alto índice de variação na maioria dos caracteres. As distâncias genéticas entre os pares de acessos variaram de 0,09 a 1,87, com média de 1,39. O método UPGMA dividiu os acessos em cinco grupos, enquanto o de Tocher formou 24 agrupamentos. Os cinco acessos indicados como mais divergentes devem compor programas de intercruzamentos, para obtenção de genótipos superiores.Termos para indexação: Euterpe oleracea, variabilidade, análise multivariada, agrupamento, distância genética. Genetic divergence among accessions of assai palm based on morphoagronomic descriptorsAbstract -The objective of this research was to estimate the genetic divergence among accessions of the assai palm, sampled in the germplasm collection of Embrapa Amazônia Oriental based on morphoagronomic traits, at Belém, PA. The 22 morphoagronomic traits were evaluated in 87 accessions, from 1995 to 2001. Among the 22 traits, seven were relative to the plant, three to the flowering, three to the fruit, and nine to the fruit production. The traits were analyzed using univariate and multivariate analysis. The estimates of the dissimilarities were obtained by the average Euclidian distance with standardized data, and the groupings by UPGMA and Tocher methods. The accessions presented high variation index in the majority of the characters. Genetic distances among accession pair varied from 0.09 to 1.87, with average of 1.39. The method UPGMA divided the accessions into five groups, while the Tocher method formed 24 groupings. The five accessions indicated as more divergent must be used in breeding programs aiming at the obtention of superior genotypes.

Genetic divergence among white-type acai palm accessions based on morpho-agronomic characters

“…Similar values were found by Oliveira et al (2007) and Galate et al (2012), who evaluated samples of purple acai palm from different locations in the Amazon Estuary, using the same morpho-agronomic descriptors. However, in the present study, the percentage of variation accumulated up to the eighth component was much greater -above 92%.…”

“…Oliveira et al (2007) also reported a strong genetic divergence, while evaluating 87 accessions of the purple type of acai, through 22 morpho-agronomic descriptors, including the majority of the characters evaluated in the present study. A great divergence between the matrixes of acai palms, which occur naturally in different areas, was also observed by Galate et al (2014).…”

“…Regarding sources, two groups were formed by Tocher's method, with the same make up as in the UPGMA. Oliveira et al (2007) and Galate et al (2014) used the same methods and obtained similar results, when determining the genetic divergence among purple acai palms. This divergence could be due to a strong effect of the origin of the acai crops, most of them from the floodplains around the Amazon estuary, which are inundated areas affected by the movement of the tides, i.e., inundation occurs daily, according to the ebb and flow of the waters from the rivers and creeks, with an indirect link to the movement of the sea (Marinho, 2009).…”

Artificial neural network analysis of genetic diversity in Carica papaya L.

“…This approach was also used to characterize the genetic structure of the sampled plants as criteria and indicators for the selection of promising genotypes for breeding programs, aside from the conservation of germplasm of the sampled species (Arriel et al 2006, Oliveira et al 2006, Viana et al 2006, Oliveira et al 2007). …”

Genetic Divergence among Camu-Camu Plant Populations Based on the Initial Characteristics of the Plants

“…This constant structure, through the formation of group coincidence in the utilization of complementary methods for morpho-agronomic characteristics, generates greater confidence in the results (Sudré et al, 2005;Oliveira, Ferreira, & Santos, 2007;Negreiros, Bergo, Miqueloni, & Lunz, 2013). Thus, the BRB AB and BRB AT populations that had to be classified as one group (Group 4), with the Tocher method, were classified by canonical variables within group III, together with the BRB EV, BRB ON and IAB populations.…”