We used agromorphological and random amplified polymorphic DNA (RAPD) molecular marker data to identify duplicate common bean (Phaseolus vulgaris L. Fabaceae) accessions in the Common Bean Germplasm ...Bank of the Agronomical Institute - IAC (Banco de Germoplasma de feijoeiro do Instituto Agronomico de Campinas (IAC), SP, Brazil). A total of 116 accessions with the same names and similar agromorphological traits was analyzed. The divergence between the accessions was initially evaluated by means of the agromorphological descriptors using single linkage clustering, from the Euclidean distance. Multivariate analysis identified four duplicate accessions (Carioca Lustroso, Bico de Ouro, Jamapa and Preto), with 17 other same-name accessions being suspected duplicates due to their low divergence levels. Accessions with low genetic distance values (indicating that they were duplicates) were further compared using RAPD markers which confirmed the results of the multivariate analyses in relation to the four duplicate accessions, although only two of the other 17 suspect accessions were confirmed to be duplicates, in this case of accessions IAPAR 57 and Sacavem. These results show that the combined use of agromorphological and molecular information allowed a better characterization of the acessions in the common bean Germplasm Bank.
Carlos Chagas, a Brazilian physician, discovered the American
trypanosomiasis in 1909. Like other remarkable discoveries of those
days, his work helped to articulate the insect-vector theory and ...other
theoretical guidelines in tropical medicine. Unlike all other
discoveries, all the stages of this work were accomplished in a few
months and by a single man. Chagas' discovery was widely recognized at
home and abroad. He was twice nominated for the Nobel Prize - in 1913
and in 1921 -, but never received the award. Evidence suggests that the
reasons for this failure are related to the violent opposition that
Chagas faced in Brazil. The contentions towards Chagas were related to
a rejection of the meritocratic procedures that gave him prominence, as
well as to local petty politics.
O Nordeste é a principal região produtora de melão do País, contribuindo com mais de 90% da produção nacional. Entretanto, o "amarelão do meloeiro", doença associada à presença de um novo vírus, o ...Melon yellowing-associated virus (MYaV), vem afetando a cultura desde 1999. Este trabalho teve como objetivo detectar a ocorrência do MYaV em meloeiros exibindo sintomas suspeitos da doença nos estados que são os maiores produtores da Região Nordeste. Em novembro de 2007, plantios comerciais de melão foram inspecionados para avaliar a ocorrência do "amarelão". Um total de 374 plantas foi coletado em áreas produtoras dos estados do RN (54) e CE (37) e também, do Submédio do Vale do São Francisco (283), situado nos Estados da BA e PE. A detecção do MYaV nas amostras foi realizada por DAS-Elisa utilizando-se anticorpos policlonais desenvolvidos pela Embrapa Hortaliças. Extratos preparados a partir de folhas e de hastes das plantas coletadas foram utilizados como antígeno. O MYaV foi detectado em 58,0% do total de plantas avaliadas, sendo que a concentração viral foi maior em hastes do que em folhas. A quantidade de plantas infectadas foi maior em amostras coletadas no RN (96,3%) e CE (75,7%) que no Submédio do Vale do São Francisco (PE e BA, com 48,4%). Estes resultados revelaram a ampla disseminação do MYaV nas principais áreas produtoras de melão da Região Nordeste e demonstraram a eficiência dos anticorpos na detecção viral.
The Northeast Region of Brazil is the main melon-producing region of the country, being responsible for more than 90% of the total national production. A new disease, known as "yellowing of melon plants", which has been associated to a new viral agent, the Melon yellowing-associated virus (MYaV), has been reported to cause damage on this crop since 1999. In this study we evaluated the occurrence of the MYaV in melon plants exhibiting suspicious symptoms of the disease in major melon growing states of the Northeast region. In November 2007, commercial melon fields were inspected for the occurrence of this virus. A total of 374 plants was collected in melon fields of the States of Rio Grande do Norte (54) and Ceará (37) and in the Submédio do Vale do São Francisco (283), in Bahia and Pernambuco States. Sample evaluation was performed by DAS-Elisa using polyclonal antibodies developed at the Embrapa Hortaliças for MYaV detection. Extracts prepared from leaves and stems of symptomatic plants were used as antigen. The MYaV was detected in 58.0% of the collected samples. Interestingly, the virus concentration was higher in stems than in leaves. The incidence of MYaV was higher in samples collected from Rio Grande do Norte (96.3%) and Ceará (75.7%) fields than from those in the Submédio do Vale do São Francisco (Pernambuco and Bahia, with 48.4%). These data confirmed the widespread occurrence of the virus in melon fields of the main melon-producing areas of Northeastern Brazil and the efficiency of the antibody for MYaV detection.
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