Anatomical alterations in leaves and DNA damage in cells caused by the accumulation of atmospheric pollutants can be measured by epidermal leaf analyses and Tradescantia micronuclei assay with early pollen tetrad cells. The present study examined the feasibility of using somatic and germ cells of Tradescantia pallida for biomonitoring purposes in the city of Dourados, state of Mato Grosso do Sul (MS), Brazil. Stomatal, micronucleus and epidermal leaf analyses were performed, using standard methodologies, on plants growing at three locations during six different time periods. Tradescantia micronuclei data were analyzed using SAS 9.2 software package and stomatal data were analyzed using SANEST software. Analyses of stomatal characteristics and micronuclei examination in T. pallida were found to be an efficient tool for monitoring atmospheric pollution. The micronucleus assay suggested that the number of micronuclei in early pollen tetrad cells was related to the intensity of vehicular traffic. Increased number of epidermal cells and stomata and increased stomatal density observed at locations with greater vehicular traffic are likely physiological responses of those plants to the increased gas exchange in highly polluted environments.

In the present study, genotoxicity and mutagenicity were investigated in Tradescantia pallida exposed to vehicular traffic at different sites in a high-altitude tropical climate. During March, May, July, September, and November 2014, a comet assay and micronucleus bioassays were conducted on young inflorescences and leaves of T. pallida collected from twelve towns in the southern region of Mato Grosso do Sul with different amounts of vehicular traffic. Weather parameters (temperature, relative humidity and rainfall) were measured and vehicles were counted to determine traffic levels in each town. A higher frequency of genotoxic and mutagenic damage was observed in the municipality of Dourados. The highest frequency of genetic damage was observed in September and November according to both assays. Relative humidity and rainfall were inversely proportional to the frequency of genetic damage in T. pallida during the collection period. Based on these results, we conclude that the bioassays are efficient for assessing the effects of vehicular traffic in these towns with respect to weather conditions over time. These bioassays can be applied to identify risk areas, which are determined by climatic conditions and air pollutants released.

Plants growing in localities with more intense vehicular traffic had greater quantities of micronuclei as well as higher frequencies and average numbers of stomata than localities with less traffic, indicating the presence of atmospheric contaminants that damaged their DNA.

ABSTRACT. The aim of the study was to detect polymorphisms in the leptin gene and to determine the association of these polymorphisms with growth and carcass traits in Nellore cattle. The single nucleotide polymorphisms (SNPs) -1457 (AJ571671:g.-1457A>G) and A59V (AF536174.1:g. 321C>T), as well as the microsatellite BM1500 (3.9 kb downstream), were genotyped. The measures of body weight and ultrasound examinations (rib eye area, back, and rump fat thickness) were performed in 3 different periods of animal management. During the first period, the animals were fed with grass and mineralized salt ad libitum. In the second period, they received grass and concentrate, and in the third, only concentrate. After the slaughter of animals, data were collected for classification and typification of carcasses. No significant association was found between the variables assessed and SNP -1457. Conversely, SNP A59V was associated with rump fat thickness and muscle color post-slaughter. BM1500 was associated with rump fat thickness in the first period (pre-slaughter), subcutaneous fat thickness 3003 ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 13 (2): 3002-3012 (2014) Leptin gene variations in Nellore cattle in the second, weight of the animals in the third, and length of the carcass after slaughter. These results suggest that SNP A59V and the microsatellite BM1500 might be useful for marker-assisted selection in Nellore cattle.

ABSTRACT. Sheep of the Pantaneiro breed and seven other breeds, raised in the State of Mato Grosso do Sul, Brazil, were genotyped using eight microsatellite loci. The aim of the present study was to determine the genetic variability, phylogenetic relationship, and patterns of gene introgression and miscegenation among the animals surveyed, to obtain information about the genetic structure of locally adapted sheep in Mato Grosso do Sul. A total of 195 animals were used for genetic analysis. The Pantaneiro breed had the largest average number of alleles/locus (9.25), and higher allelic richness (6.95), while the Dorper population had the lowest values for these parameters (4.88 and 3.86, respectively). Analysis of genetic distance values and genetic structure between populations made it possible to characterize these animals with regard to distinct genetic groups. Average expected heterozygosity ranged from 0.72 (Pantaneiro) to 0.55 (Dorper), while average observed heterozygosity ranged from 0.63 (White Dorper) to 0.54 (Dorper). On the basis of the statistical parameters evaluated, it 5459 ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 12 (4): 5458-5466 (2013) Genetic diversity in Pantaneiro sheep was possible to demonstrate that when compared to other populations, the Pantaneiro breed represented a reservoir of genetic diversity with rare and useful alleles for genetic improvement, emphasizing the importance of preserving the breed.