Genetic diversity in section Rhizomatosae of the genus Arachis (Fabaceae) based on microsatellite markers

The genus Arachis (Fabaceae) native to South America, contains 80 species divided into nine sections, three of which contain species of special economic importance such as the cultivated peanut (Arachis hypogaea), belonging to the section Arachis, and some perennial forage species from sections Caulorrhizae and Rhizomatosae. We used microsatellite markers to assay genetic variability among 77 accessions of four species from section Rhizomatosae, the diploid Arachis burkartii (2n = 2x = 20) and the tetraploid Arachis glabrata, Arachis pseudovillosa and Arachis nitida (2n = 4x = 40). A total of 249 alleles were found in the fifteen loci analyzed and a high degree of intra and interspecific polymorphism was detected. The lowest intraspecific variation occurred in Arachis burkartii, while the smallest estimated interspecific value was between A. nitida and A. pseudovillosa and the largest was between A. burkartii and A. nitida. High observed heterozygosity was detected in A. glabrata. The diploid accessions grouped in one cluster and the tetraploid accessions in another. It was possible to distinguish all 77 accessions and the genetic distance between accessions could not be correlated with geographic origin.

Transferability and use of microsatellite markers for the genetic analysis of the germplasm of some Arachis section species of the genus Arachis

The Arachis section is the most important of the nine sections of the genus Arachis because it includes the cultivated peanut, Arachis hypogaea. The genetic improvement of A. hypogaea using wild relatives is at an early stage of development in spite of their potential as sources of genes, including those for disease and pests resistance, that are not found in the A. hypogaea primary gene pool. Section Arachis species germplasm has been collected and maintained in gene banks and its use and effective conservation depends on our knowledge of the genetic variability contained in this material. Microsatellites are routinely used for the analysis of genetic variability because they are highly polymorphic and codominant. The objective of this study was to evaluate the transferability of microsatellite primers and the assay of genetic variability between and within the germplasm of some species of the Arachis section. Fourteen microsatellite loci developed for three different species of Arachis were analyzed and 11 (78 percent) were found to be polymorphic. All loci had transferability to all the species analyzed. The polymorphic loci were very informative, with expected heterozygosity per locus ranging from 0.70 to 0.94. In general, the germplasm analyzed showed wide genetic variation.

Heterologous microsatellite primer pairs informative for the whole genus Arachis

The genus Arachis currently comprises 69 described species, some of which have potential and real value as human and animal foods. These Arachis species have been collected and maintained in germplasm banks to provide material that can be used as sources of genes in breeding programs and for the selection of new cultivars. One of the principal objectives of germplasm conservation is the evaluation of genetic variability, which is best conducted using molecular markers. We investigated the use of heterologous primers to amplify microsatellite loci that could be used to evaluate genetic variability in Arachis germplasm. Fifteen microsatellite primer pairs were tested in 76 accessions of 34 species from the nine Arachis sections. The data indicated that heterologous primers were very useful in Arachis since they had high transferability among the species (91 percent) and allowed the amplification of very polymorphic putative loci, which allowed both the characterization of most accessions and to make inferences about the mating systems of some species analyzed. Our data also revealed that the germplasm analyzed showed high variability, even when represented by few accessions.

Análise cromossômica e molecular do javali europeu Sus scrofa scrofa e do suíno doméstico Sus scrofa domesticus / Cytogenetic and molecular analysis of a european wild boar Sus scrofa scrofa and domestic swine Sus scrofa domesticus

A presente investigação teve como objetivos: analisar animais presentes em diferentes criações de javalis no estado de São Paulo, com o intuito de auxiliar a identificação de javalis "puros" assim como javalis híbridos provenientes do cruzamento com o suíno doméstico, para tanto foram utilizadas avaliação do fenótipo dos animais, análises citogenéticas e da técnica molecular de RAPD (Random Amplified Polymorphic DNA).O estudo do número de cromossomos nas células diplóides em 104 animais destinados a análise citogenética e fenotípica, revelou polimorfismo de 2n=36, 37 e 38 cromossomos. Por meio da técnica de bandamento GTG foi possível identificação da translocação Robertsoniana entre os cromossomos 15 e 17 como responsável por esse polimorfismo. Todavia, somente com a análise citogenética isolada, não foi possível determinar se a origem desse polimorfismo é decorrente das hibridações com o suíno doméstico ou se são características inerentes ao javali. Contudo, quando associado a análise citogenética com as características fenotípicas, foi possível identificar a existência de hibridações. A análise citogenética nos animais submetidos a técnica de RAPD, revelou 2n=36 cromossomos nos 16 javalis assim como 2n=38 cromossomos nos 11 suínos e, por meio dessa técnica, foram possíveis agrupamentos, separando o suíno doméstico, javali e um possível híbrido revelando-se uma técnica com potencial no auxílio da identificação de híbridos

Acid phosphatase polymorphism within and among populations of Cauliflower (Brassica oleracea var botrytis)

Eighty-one lines of cauliflower (Brassica oleracea var. botrytis) from 12 populations used to produce commercial hybrids in Brazil were screened for polymorphism in the acid phosphatase system, in order to evaluate the usefulness of this marker for the determination of the parental contamination level in hybrid seeds. Little polymorphism was detected in the examined lines, but the system appeared to be very useful for hybrid identification, since the only condition required was polymorphism between the two parental lines. If the analyzed lines were used for hybrid production, 8.4 percent and 12.3 percent of the possible crosses would result in hybrids which can be positively identified using the APS-1 and B1 loci, respectively. If only one plant of each homozygous type (SS or FF) was analyzed in each population, 41 percent and 50 percent of the possible crosses would result in hybrids which can be positively identified using the APS-1 and B1 loci, respectively

Evaluation of nine microsatellite loci and misidentification paternity frequency in a population of Gyr breed bovines

Paternity misidentification is harmful due to the reduction in annual genetic earnings of the population and because it endangers an efficient genetic improvement program. The objectives of the present study was to evaluate nine microsatellites in Paternity Testing and to investigate misidentification paternity frequency in families of Gyr breed bovines population. In the present experiment blood samples from forty Gir breed families ( bull / cow / calf ), registered pure breed in the Zebu Breeders Brazilian Association (ABCZ) were used. The most part of the microsatellites used in this work were recommended by the International Society of Animal Genetics (ISAG). The genomic DNA extraction was performed from whole blood samples. The microsatellites TGLA122, TGLA126, BM1824, BMS2533, SPS115, ETH3, ETH10, ETH225 and POTCHA were amplified by PCR. The amplification products were separated by electrophoresis in denaturing polyacrylamide gel. from the obtained data, allele frequencies, Gene Diversity, Polymorphism Informative Content and Probability of Exclusion for each microsatellite marker were calculated. the genotype frequencies, Heterozygosity, Combined Probability of Exclusion and Probability of Paternity have also been calculated in the considered families. The Combined Exclusion Probability for all microsatellites was around 0.9789. The Paternity Testing results showed misidentification in eleven of the 40 studied families, that means, 27.5 percent of the sample. The Paternity Probability ranged from 0.8691 to 0.9999, and the mean was 0.9512