ABSTRACT
The aim of this research was to evaluate the genetic divergence between 164 genotypes of Manihot esculenta from the South-Central mesoregion of the State of Mato Grosso. The genotypes are from projects conducted by the Laboratory of Genetic Resources & Biotechnology of the University of the State of Mato Grosso, Cáceres-Mato Grosso (UNEMAT), and the Brazilian Public Agricultural Research Corporation - Agrosilvopastoral (EMBRAPA). The agronomic descriptors evaluated were plant height, height of first branching, branching levels, weight of the aerial part of the plant, total weight of the plant, number of roots per plant, average weight of roots per plant, yield of commercial roots, yield of non-commercial roots, number of rotten roots per plant and harvest index. For the analysis of genetic divergence, multivariate analysis based on the standardized Euclidean mean distance was employed, later performing the Hierarchical UPGMA and Tocher Optimization agglomerative methods. The degree of preservation of the genetic distances in the dendrogram was verified using the Cophenetic Correlation Coefficient. The Singh criterion was used to quantify the relative contribution of characteristics to genetic divergence. The genotypes presented genetic dissimilarity for the evaluated characteristics and based on the results of the dissimilarity matrix and groupings, it is recommended the crossings between the genotypes allocated in group II with the genotype allocated in group V, for the development of segregated populations with high genetic variability.
Subject(s)
Genetic Variation , Manihot , Plant BreedingABSTRACT
Objective To explore the correlation between the genetic dissimilarity and heterozygosity of mates and the patho?genicity of Schistosoma japonicum in the definitive host. Methods By using seven microsatellite loci markers,S. japonicum genotyping of sixteen pairs randomly mated was performed,the genetic dissimilarity and heterozygosity were calculated between the mates,and the correlation between the genetic dissimilarity and heterozygosity of the mates and the pathogenicity of S. japon?icum in the definitive host was evaluated. Results There was a significant correlation between the genetic similarity of S. ja?ponicum mates and the mean number of eggs per worm pair in the liver and intestinal tissue (r = 0.501 6 ,P 0.05;r=0.265 3,P>0.05,respectively)and the average diameter of granuloma in the liver(r=-0.272 7,P>0.05),respec?tively. There was no correlation between the heterozygosity of the mates and all the pathological parameters of S. japonicum in the definitive host(P > 0.05). Conclusions There is the correlation between the genetic dissimilarity of the mates and the pathogenicity of S. japonicum in the definitive host,and the genetic dissimilarity is greater,pathogenicity is weaker. There is no correlation between heterozygosity of the mates and the pathogenicity of S. japonicum in the definitive host.
ABSTRACT
Maytenus ilicifolia e M. aquifolium são espécies nativas do Brasil, popularmente conhecidas como espinheira-santa, sendo indicadas para gastrite e para úlcera estomacal. A Embrapa Clima Temperado e a Universidade Federal de Pelotas (UFPel) mantêm um banco de germoplasma destas espécies. Com o objetivo de identificar a variabilidade fenotípica para alguns caracteres morfológicos em matrizes de espinheira-santa, estimar a dissimilaridade e agrupar os acessos através de análises multivariadas, 105 acessos foram caracterizados morfologicamente. Foram avaliados os caracteres comprimento e largura de fruto, número de sementes por fruto, comprimento e largura de folha, relação comprimento/largura de folha e número de espinhos por folha. Foi estimada a distância euclidiana e os acessos foram agrupados pelo método de otimização de Tocher. Foi observada uma ampla variabilidade para todos os caracteres analisados. O número de espinhos por folha foi o caráter que mais contribuiu para a divergência. Os caracteres morfológicos permitiram separar os acessos em sete grupos. A maior dissimilaridade foi entre os acessos 57 (M. ilicifolia) e 91 (M. aquifolium). Não foi evidenciada uma separação de acordo com a localização geográfica dos acessos. Na análise de agrupamento foram identificados dois grupos que apresentavam tanto acessos de M. ilicifolia quanto de M. aquifolium, o que indica proximidade filogenética entre estas espécies.
Maytenus ilicifolia and M. aquifolium are native Brazilian species popularly known as espinheira-santa, being indicated for gastritis and stomach ulcer. Embrapa Clima Temperado and Universidade Federal de Pelotas (UFPel) keep a gene bank of these species. With the objective of identifing phenotypic variability for some morphological characters in matrices of espinheira-santa, estimating dissimilarity and clustering accessions through multivariate analysis, 105 accessions had been morphologically characterized. The characteristics evaluated were fruit length, fruit width, number of seeds per fruit, leaf length, leaf width, leaf length/leaf width ratio and number of thorns per leaf. The euclidean distance was estimated and accessions were clustered by Tocher optimization method. A wide variability for all the characteristics analyzed was observed. The number of thorns per leaf was the characteristics that more contributed to the divergence. The morphological characteristics enabled to separate the accesses in seven clusters. The higher dissimilarity was between accessions 57 (M. ilicifolia) and 91 (M. aquifolium). There was no evidence of a separation in accordance to the geographic localization of the accessions. In the clustering analysis were identified two clusters that had accessions of both species, M. ilicifolia and M. aquifolium, indicating phylogenetic relatedness between these species.