Dissimilaridade genética em mutantes de aveia tolerantes e sensíveis a ácidos orgânicos

Abstract

RESUMOPara que o cultivo da aveia (Avena sativa L.) seja também alternativa economicamente viável em solos de várzea, faz-se necessário a utilização de cultivares tolerantes aos principais ácidos orgânicos produzidos pela decomposição da matéria orgânica gerada em cultivos com plantio direto. Este trabalho objetivou determinar a dissimilaridade genética entre famílias mutantes M 3 e a cultivar UFRGS 14 de aveia mediante a utilização de marcadores ISSR, e detectar regiões genômicas associadas ao caráter tolerância a ácidos orgânicos. Foram avaliadas 30 famílias mutantes (M 3 ), pertencentes ao banco de mutantes de aveia do Centro de Genômica e Fitomelhoramento da Faculdade de Agronomia "Eliseu Maciel". As famílias estudadas foram originadas da cultivar UFRGS 14 irradiada com raios gama (Co 60 ) na dose de 400 Gy. A caracterização genética foi realizada utilizando-se a técnica de marcadores ISSR. Pelos resultados verifica-se que os oligonucleotídeos UBC 854, 855, e 811 permitiram detectar regiões genômicas relacionadas à tolerância à toxicidade por ácidos orgânicos, enquanto os oligonucleotídeos UBC 850 e 826 possibilitaram identificar regiões genômicas associadas à sensibilidade. Palavras-chave: marcadores moleculares; marcadores ISSR; raios gama (Co 60 ). ABSTRACT GENETIC DISSIMILARITY IN OAT (AVENA SATIVA L.) TOLERANT AND SENSITIVE MUTANTS TO ORGANIC ACIDSIn order to cultivate oats (Avena sativa L.) as an economically alternative in low lands, it is necessary to use cultivars tolerant to the main organic acids produced by organic matter decomposition resulting from no tillage systems. The objectives of this work were estimate genetic dissimilarity among M 3 mutant families and the oat cultivar UFRGS 14 using ISSR markers; and to detect genomic regions associated with organic acids toxicity. Thirty M 3 mutant families from the Plant Genomic Center of the College of Agronomy "Eliseu Maciel", derived from the cultivar UFRGS 14 irradiated with gamma ray (Co 60 ) at 400 Gy dosage were used. The genetic characterization was carried out using the ISSR marker technique. The results indicated that UBC 854, 855 and 811 primers allowed the identification of genomic regions related to organic acid toxicity tolerance, while UBC 850 and 826 primers of genomic regions associated to organic acid sensitivity.

Induction of genetic variability and plant development in palisade grass evaluated in M2 mutants

“…Detected genetic dissimilarity demonstrates that mutation induction generated high genetic variability, which was also found in other studies with Poaceae family species, as these proceeded in Brazil with oat (Coimbra et al, 2004;Souza et al, 2005). This increase in variability provides high importance to Urochloa, mainly due to reproductive difficulties that are provided by the presence of apomixis, present in the genotypes of U. brizantha studied in the Brazilian germplasm bank (Resende et al, 2008;Valle et al, 2009) and chromosomal irregularities (Fuzinatto et al, 2012).…”

“…This species exhibit difficulty in generating new natural recombination because of its narrow genetic basis (Muller, 1927). In Brazil, research with the mutation induction in the Poaceae family species were performed by Coimbra et al (2004) and Souza et al (2005), which indicated success in increasing genetic variability and changes in desired traits, standing out as an alternative to generate genetic variability. A mutation is inclined to be a specific change in a gene or act on chromosomes (Allard, 1971), which highlight successive random changes in nucleotides.…”

Genetic characterization of fig tree mutants with molecular markers

“…This single polymorphic band was obtained from the combination of 5 primers, and polymorphism occurred between individual 3 and the others, as can be observed in Figure 2, which shows the polyacrylamide gels with all the combinations. Regarding the number of polymorphic bands, a study on genetic dissimilarity in oat mutants generated by irradiation with gamma rays identified a total of 880 markers, of which 195 were polymorphic for 18 ISSR primers, resulting in an average of 48.9 markers and a total of 10.8 polymorphic markers (Souza et al, 2005). These results agree with those obtained in a research on genetic variation and clonal diversity of Psammochloa villosa (Poaceae), which found 122 polymorphic bands for 12 primers evaluated (Li and Ge, 2001).…”

Variabilidade Genética De Ostras Coletadas No Estuário Do Rio Subaé, São Francisco Do Conde - Ba

“…Cada faixa corresponde a uma sequência de DNA delimitada por dois microssatélites invertidos. As sequências-alvo dos ISSRs são abundantes ao longo do genoma de eucariontes e evoluem rapidamente, bem como têm provado serem úteis dentro de populações de estudos genéticos, destacando-se em detecção clonal, diversidade e revelação de indivíduos proximamente relacionados (Souza et al, 2005).…”