Alismatales sensu stricto: cytogenetics analysis with conventional techniques, banding and rDNA sites

A ordem Alismatales corresponde a um dos clados basais de monocotiledôneas e se apresenta predominantemente em hábitats aquático ou semi-aquático. Nesse trabalho, objetivou-se compreender as relações taxonômicas internas e a evolução cariotípica em um grupo de Alismatales de ocorrência exclusivamente neotropical. Para isso, foram realizados estudos citogenéticos em cinco espécies de Alismataceae e quatro de Limnocharitaceae baseados na coloração convencional com uso de Giemsa 2%, marcação das RONs com nitrato de prata, bandeamento cromossômico C, dupla coloração com os fluorocromos CMA/DAPI e hibridização in situ fluorescence (FISH) com sondas de DNA ribossomal 45S. Em Hydrocharitaceae, foi usada apenas a coloração convencional com Giemsa 2%. Na família Alismataceae, as espécies de Echinodorus apresentaram 2n=22 e padrão de bandas CMA/DAPI e C/CMA/DAPI localizadas na região do braço curto e satélite de dois dos menores pares acrocêntricos A hibridização in situ com sondas de DNAr 45S coincidiu em geral, com os blocos observados com uso dos fluorocromos, com exceção de E. andrieuxii que obteve apenas três sítios. E. lanceolatus foi a única espécie que apresentou bandas DAPI+, localizadas nas regiões teloméricas de sete pares acrocêntricos. Em Limnocharitaceae,as regiões marcadas pelos fluorocromos CMA/DAPI e bandeamento C/CMA+ corresponderam às RONs e aos dois sítios de DNAr 45S em Hydrocleys nymphoides (2n=16) e aos quatro em Limnocharis flava (2n=20). Entretanto, L. laforestii diferiu em relação aos sítios de DNAr 45S, que foram apenas dois. As espécies Hydrocleys nymphoides e H. martii tiveram a posição da heterocromatina rica em GC associada ao satélite localizada em um par acrocêntrico pequeno na primeira, e em um par metacêntrico de tamanho intermediário, na segunda. O único representante de Hydrocharitaceae, Limnobium laevigatum, obteve 2n=28 e cariótipo assimétrico do tipo bimodal, assim como as demais espécies. Nesse grupo analisado, técnicas citogenéticas mais refinadas detectaram alterações cromossômicas estruturais importantes para a evolução cariotípica em Alismatales.The order Alismatales corresponds to one of the basal monocotiledones clads and is found predominantly in habitats aquatic or semiaquatic. The present work aimed to understand the internal taxonomic relations and the karyotype evolution in a monofiletic group of Alismatales of exclusively neotropical occurrence. Five species of Alismataceae and four of Limnocharitaceae were investigated using 2% Giemsa, silver nitrate staining, C-banding, CMA/DAPI fluorochromes staining and fluorescence in situ hybridization (FISH) with probes of ribossomal 45S DNA. One species of Hydrocharitaceae was also staining with Giemsa 2%. In Alismataceae, the Echinodorus species showed 2n=22 and CMA/DAPI and C/CMA/DAPI bands located in the short arm and satellite of two of the smallest acrocentric chromosomes pairs. Fluorescence in situ hybridization with 45S rDNA probe co-localized in general, with the blocks revealed after fluorochromes staining, with exception of E. andrieuxii, for which only three 45S rDNA sites were detected. E. lanceolatus was the only species with DAPI+ bands, which were located in the telomeric regions of seven acrocentric pairs. In Limnocharitaceae, Hydrocleys (2n=16) and Limnocharis (2n=20), the CMA+ regions had corresponded to the RONs and the 45S rDNA sites in Hydrocleys nymphoides and Limnocharis flava. L. laforestiidiffered in relation to the number of 45S rDNA because two sites were observed in the later. In Hydrocleys nymphoides and H. martii the GC-rich in the heterochromatin was associated with the satellite located in the smallest acrocentric pair, and in a metacentric pair of intermediate size in the later. The only representative of Hydrocharitaceae, Limnobium laevigatum showed 2n=28 and an asymmetric bimodal karyotype as well as the other investigated species. In the group examined the refined techniques cytogenetic provided information such as detection of structural chromosome changes important for the karyotype evolution in Alismatales.Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNP

Aspectos de biologia floral de cajueiros anão precoce e comum Floral biology aspects of the early dwarf and common cashew

O conhecimento da biologia floral é de suma importância para o desenvolvimento da cultura do cajueiro (Anacardium occidentale L.). Com relação aos aspectos botânicos, as características morfológicas das flores contribuíram efetivamente para a determinação das espécies do gênero Anacarduim conhecidas. No presente trabalho, objetivou-se estudar a biologia floral dos cajueiros anão precoce e comum. A pesquisa foi desenvolvida na área experimental do Departamento de Fitotecnia, Centro de Ciências Agrárias, Universidade Federal do Piauí, em Teresina, PI, avaliando-se nove clones de cajueiro anão ("CAP 14", "Embrapa 09", "Embrapa 50", "Embrapa 51", "Embrapa 76", "Embrapa 183", "Embrapa 189", "FAGA 01", "FAGA 11") e um clone de cajueiro comum ("CCA"), utilizando-se quatro panículas por planta, cada uma com orientação norte, sul, leste e oeste. Os tipos varietais, cajueiro comum e anão precoce, apresentam pouca variação para a maioria dos caracteres avaliados. A proporção entre flores hermafroditas e o total de flores, em cajueiro comum, pode levá-lo a uma maior produção de frutos por panícula do que nos clones de cajueiro anão precoce analisados. O número de frutos desenvolvidos é bastante reduzido nos dois tipos varietais. As panículas situadas em diferentes orientações cardeais são semelhantes em todos os clones estudados quanto aos aspectos relacionados à biologia floral do cajueiro.The knowledge of the floral biology is very important for the development of the cashew's culture (Anacardium occidentale L.). In relation to botanical aspects, the morphological characteristics of flowers contributed effective to determination of the well-known species of Anacardium. It was aimed at studing the floral biology of the early dwarf and common cashew. The research was developed in the experimental area of the Department of Fitotecnia, Centro de Ciências Agrárias, Universidade Federal do Piauí, in Teresina, PI, and nine clones of dwarf cajueiro ('CAP 14', 'Embrapa 09', 'Embrapa 50', 'Embrapa 51', 'Embrapa 76', 'Embrapa 183', 'Embrapa 189', 'FAGA 01', 'FAGA 11') and a clone of common cashew ('CCA'), were evaluated using four paniculae per plant, in north, south, east and west orientation. The varietal types, common and early dwarf cashew, present little variation for most of the evaluated characteristics. The common cashew presents a larger proportion between the number of hermaphrodite flowers and the total number of flowers than the early dwarf cashew clones; this may facilitate a larger production of fruits in the common cashew. The number of developed fruits is very low in both varietal types. The paniculae placed in different cardinal orientations are similar in all the clones in relation to the aspects related to the floral biology of the cashew

Toxicity at the cellular level of artificial synthetic flavorings

The goal of the present study was to evaluate the cytotoxicity and genotoxicity of artificial synthetic flavoring agents Cookie and Tutti-frutti. To this end, root meristem cells of Allium cepa L. were exposed to these substances in exposure times of 24 and 48 hours using individual doses of 0.3; 0.6 and 0.9 mL and doses combined as follows: 0.3 mL + 0.3 mL; 0.6 mL and 0.9 mL + 0.6 mL + 0.9 mL. After applying the treatments, root meristems were fixed, hydrolyzed, stained and analyzed a total of 5,000 cells using an optical microscope to evaluate each dose and combined treatment. All three doses of Cookie flavoring and combined treatments significantly inhibited cell division of the tissue studied. Doses of Tutti-Frutti caused no change in cell division rate. In addition, doses of both flavorings and treatments combining these solutions induced cell aberrations in a significant number of cells to the A. cepa system. Therefore, under these analytical conditions, Cookie flavoring and combined doses were cytotoxic and genotoxic, and Tutti-Frutti flavoring, although non-cytotoxic, demonstrated genotoxic action. The goal of the present study was to evaluate the cytotoxicity and genotoxicity of artificial synthetic flavoring agents cookie and tutti-frutti. To this end, root meristem cells of Allium cepa L. were exposed to these substances in exposure times of 24 and 48 hour using individual doses of 0.3; 0.6 and 0.9 mL and doses combined as follows: 0.3 mL + 0.3 mL; 0.6 mL and 0.9 mL + 0.6 mL + 0.9 mL. After applying the treatments, root meristems were fixed, hydrolyzed, stained and analyzed a total of 5,000 cells using an optical microscope to evaluate each dose and combined treatment. All three doses of cookie flavoring and combined treatments significantly inhibited cell division of the tissue studied. Doses of tutti-frutti caused no change in cell division rate. In addition, doses of both flavorings and treatments combining these solutions induced cell aberrations in a significant number of cells to the A. cepa system. Therefore, under these analytical conditions, cookie flavoring and combined doses were cytotoxic and genotoxic, and tutti-frutti flavoring, although non-cytotoxic, demonstrated genotoxic action.

Optimized method for dna extraction and PCR amplification in aroeira tree

Molecular markers are important tools in the characterization of plant genetic diversity and can provide support for conservation strategies for endangered populations. The different molecular techniques involve the evaluation of many individuals; therefore, it is crucial to have fast, efficient, and inexpensive methods for DNA extraction. Given the importance of the Aroeira (Myracrodruon urundeuva Fr. All.) it is pertinent to optimize a protocol that allows the obtainment of intact and pure DNA, aiming to assist conservation strategies for this species that is threatened with extinction. Thus, this study aimed to compare five DNA extraction methods: Dellaporta et al. (1983), Doyle and Doyle (1987) modified, Ferreira and Grattapaglia (1995), Romano and Brasileiro (2015), and Khanuja et al. (1999) and optimize the most efficient protocol for M. urundeuva. The modified DNA extraction protocol proposed by Doyle and Doyle (1987), using 100 mg of leaf tissue and 6 µl of β-mercaptoethanol was the protocol that presented the sharpest bands after DNA electrophoresis and after the reactions of amplification employing Polymerase Chain Reaction (PCR). Therefore, it is suggested to use the protocol described by Doyle and Doyle (1987) modified for the extraction of DNA from young M. urundeuva leaves to carry out techniques involving molecular markers