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The purpose of this paper was to investigate the proliferative and genotoxic activity of juices from fruits of Psidium cattleianum, also known as strawberry guava, using the Allium cepa test. Fruits were collected and frozen for subsequent juice preparation at a concentration of 125 g l−1. The treatments consisted of T1: distilled water (negative control), T2: juice of yellow strawberry guava collected in Arroio Grande, T3: juice of yellow strawberry guava collected in Palma, T4: juice of red strawberry guava collected at UFSM, and T5: 1% glyphosate solution (positive control). Eight thousand cells per treatment were analysed and the mitotic indices (MI) were calculated. The juice samples were analysed by high-performance liquid chromatography (HPLC). Statistical analyses were performed using the chi-square and Tukey tests (p < 0.05). The results show irregularities in the cell division, mainly during metaphase, and an antimitotic effect in addition to an increase in the MI in treatments containin...

The economic potential of the germplasm of medicinal species is a rich resource that should be preserved and used. The medicinal species Echinodorus grandiflorus and Sagittaria montevidensis belong to the family Alismataceae. Depurative, diuretic, anti-inflammatory, antivenin, and anti-rheumatic actions have been associated with E. grandiflorus, where the leaves are the main part used. Sagittaria montevidensis does not yet have its medicinal properties known and has a wide morphological variability, and is sometimes confused with E. grandiflorus. The present study aimed to evaluate the genotoxic and antiproliferative potential of extracts of dry leaves of E. grandiflorus and S. montevidensis on the cell cycle of Allium cepa, as well as undertake analysis by high performance liquid chromatography (HPLC-DAD) for the quantification of the compounds from the extracts. A. cepa bulb rootlets were submitted to the extracts for 24 h, prepared from plant material at two concentrations, 6 g dm−3 and 24 g dm...

Several studies have been developed to understand the physiology of seed deterioration, however, the initial steps of the deterioration process are not completely clear. Seed vigor and viability losses are also associated with genetic material damage. This study was carried out to detect cytogenetic and physiological alterations occurring during the deterioration process of wheat seeds, due to artificial aging stress. Two cultivars, Ônix and Fundacep Campo Real, were submitted to six different treatments: control (T1), 24 (T2), 48 (T3), 72 (T4), 96 (T5) and 120 (T6) hours under artificial aging conditions: 42 °C and 100% relative humidity. Germination and vigor tests (First Count of Germination, Electrical Conductivity, Seedling Emergence in the Field and Emergence Speed Index) were performed. Cytogenetic evaluations were performed through smear technique for root tips, stained with 2% acetic orcein. Total number of cells under division and mitotic index (MI) were determined. According to results, vigor and mitotic index were affected due to deterioration process induced by artificial aging stress. A reduced number of dividing cells were observed in seeds submitted to prolonged period of aging. Chromosomal abnormalities in mitotic cells of aged seeds were detected with the occurrence of micronuclei, chromosome breaks and bridges. Inúmeros estudos têm sido desenvolvidos visando entender a fisiologia da deterioração de sementes, entretanto, as etapas iniciais desse processo ainda não estão completamente elucidadas. A perda do vigor e da viabilidade das sementes também têm sido associada aos danos no material genético. Este estudo tem por objetivo avaliar alterações citogenéticas e fisiológicas no processo de deterioração de sementes de trigo , submetidas ao envelhecimento artificial. Duas cultivares foram utilizadas, Ônix e Fundacep Campo Real, submetidas a seis tratamentos: controle (T1), 24 (T2), 48 (T3), 72 (T4), 96 (T5) e 120 (T6) horas, sob envelhecimento artificial a 42 °C e aproximadamente 100% de UR. Foram efetuados os testes de germinação e vigor (Primeira Contagem, Condutividade Elétrica, Emergência de Plântulas e Indice de Velocidade de Emergência). Avaliações citogenéticas foram realizadas em tecidos de pontas de radículas. Determinou-se o número de células em divisão e o índice mitótico. O número de células em divisão e o índice mitótico foram afetados em função da deterioração induzida, pelo envelhecimento artificial. Menor número de células em divisão foi observado em sementes submetidas ao envelhecimento por períodos prolongados. Foram detectadas anormalidades cromossômicas em células mitóticas de sementes envelhecidas artificialmente, como ocorrência de micronúcleos, quebras e pontes cromossômicas.

Schinus terebinthifolius (Anacardiaceae), popularly known as red aroeira, occurs naturally in Argentina, Paraguay, Uruguay, and Brazil. It has medicinal properties and is one of the species most sought by avifauna, so it is useful in heterogeneous reforestation intended for the recomposition of degraded areas of permanent preservation. Information about chromosomes, from simple chromosome counting to detailed molecular cytogenetics, is relevant in systematic and evolutionary studies. This study aimed to perform chromosomal characterization of 22 accessions of S. terebinthifolius native to Rio Grande do Sul, aiming to verify the intraspecific variability in this species, besides the conservation and sustainable use of this species. For the determination of chromosome number, tissues of root tips were subjected to a cold pretreatment (± 4°C) for 18 h. Afterwards, the roots were fixed in Carnoy 3:1 (ethanol/acetic acid) for 24 h at room temperature and stored under alcohol (70%) under cooling. The slides wer...

Eugenia uniflora (Surinam cherry tree) is an important species in traditional medicine and is used to decrease blood pressure and prevent heartburn, bronchitis, colic and stomachaches. The tealeaves have antirheumatic, anti-dysenteric, and febrifuge properties and are used to treat diabetes. This study aimed to assess the antiproliferative, mutagenic and antimutagenic effects of the leaves and fruits of E. uniflora through the Allium cepa test. The infusions were prepared using dried leaves (6.l−1 and 24 gl−1) and the oil extraction was undertaken using hydrolyzation (0.25%, in ethanol). For juice preparation, fruit pulp with and without seeds was used. Allium cepa root tips were used for slide preparation following the squashing technique. Analysis of 500 cells for each bulb was undertaken, 250 of each root, summing 2500 cells per treatment, a total of 17,500 and 10,000 cells in the first and second experiments, respectively. The mitotic index was calculated and statistical analyses were performed. We fo...

The purpose of this study was to evaluate the antiproliferative and antigenotoxic activity of Sambucus australis Cham. & Schltdl. aqueous extracts on the cell cycle of Allium cepa L. as well as determine the phenolic compounds in such extracts. S. australis inflorescences and leaves of two accessions were used for aqueous extract preparation at concentrations: 0.003 g/ml and 0.012 g/ml. A. cepa bulbs were rooted in distilled water and, subsequently, placed in treatments for 24 hours. Rootlets were collected and fixed in modified Carnoy’s solution for 24 hours and kept. The squash technique was performed for slide preparation. Root tips were smashed and stained with 2% acetic orcein, and a total of 4000 cells per treatment were analyzed. The phenolic compounds were determined using high-performance liquid chromatography and data was analyzed using the Scott-Knott test. The results show that S. australis aqueous extracts have antiproliferative potential. Besides, the extracts prepared from S. australis leaves of both accessions at a concentration of 0.012 g/ml have shown antigenotoxic activity. The phytochemical analysis allowed us to determine the presence of flavonoids and phenolic acids, of which kaempferol and chrologenic acid were the most predominant compounds in the extracts from the inflorescences and leaves, respectively.

As plantas com potencial medicinal têm sido muito utilizadas para o tratamento de doenças no Brasil. O objetivo deste estudo foi avaliar o efeito genotóxico e antiproliferativo de infusões de Mikania cordifolia (L.F.) Willd. sobre o ciclo celular de Allium cepa L. Foram coletadas duas populações no município de Santa Maria, Rio Grande do Sul, e, para cada uma, foram preparados dois tratamentos em duas concentrações: 4g/500mL e 16g/500mL, além de um controle positivo composto por 10% de glifosato em 90% água, um herbicida amplamente utilizado com conhecido potencial genotóxico, e de um controle negativo composto por água destilada. Após período de 24 horas, as radículas foram coletadas das infusões, fixadas em etanol-ácido acético (3:1) por 24 horas e estocadas em etanol 70%. Foram analisadas células em todas as fases do ciclo celular de A. cepa, totalizando 2500, para cada grupo de bulbos. Os índices mitóticos (IM) foram calculados e submetidos à análise estatística pelo teste χ² a 5%. Os resultados mostraram que, em ambas as populações de M. cordifolia, houve redução do IM de todos os tratamentos em relação ao controle negativo. Em ambas as populações, obteve-se aumento nos valores dos índices mitóticos em função do aumento da concentração da infusão. Ocorreram aberrações cromossômicas em ambas as populações estudadas. Concluiu-se que as infusões de M. cordifolia, nas concentrações estudadas, possuem efeito antiproliferativo e mutagênico sobre o ciclo celular de A. cepa. Potential medicinal plants have been widely used for the treatment of diseases in Brazil. The objective of this study was to evaluate the genotoxic and antiproliferative effects of infusions of Mikania cordifolia (LF) Willd. on the cell cycle of Allium cepa L. Two populations were collected in Santa Maria, Rio Grande do Sul, Brazil. For each one, two treatments were prepared in different concentrations: 4g/500mL and 16g/500mL. A positive control consisting of 10% glyphosate in 90% water, which is an herbicide widely used and known for its genotoxic potential, was also prepared. Distilled water was used as negative control. After a 24-hour period, the infusion of the root tips was collected, fixed in ethanol-acetic acid (3:1) for 24 hours and stored in 70% ethanol. Cells were analyzed in all phases of the cell cycle of A. cepa, a total of 2500, for each group of bulbs. The mitotic index (MI) was calculated and statistically analyzed by the χ² test at 5%. Results showed that, in both populations of M. cordifolia, a reduction of the MI in all treatments compared with the negative control was observed. In both populations, an increase in the mitotic index values was obtained with increasing concentration of the infusion. Chromosomal aberrations were observed in both populations studied. In conclusion, infusions of M. cordifolia possess antiproliferative and mutagenic effects for the concentrations tested on the cell cycle of A. cepa.

The aims of this study were to determine the meiotic behavior and to estimate pollen grains via- bility in bean ( Phaseolus vulgaris L.) cultivars. Flower buds were collected during different developmental stages of the Mesoamerican bean cultivars IAPAR 44, Guapo Brilhante, BRS Expedito, BRS Valente, Guateian 6662 and Perola, and the Andean bean cultivar Irai, grown in a greenhouse. The meiotic index was determined by anther squashing of material fixed in absolute ethanol-glacial acetic acid (3:1) and stained with acetic orcein. No meiotic abnormalities were observed and the meiotic indices were high for all cultivars, indicating that the mismatch generated during crosses is not related to any meiotic changes. Estimation of pollen viability was made by comparing acetic orcein staining vs. Alexander's reactive: pollen viability was high in all cultivars with either stain, but was significantly higher when using the acetic orcein stain (>99%). Though some cultivar showed a significantly smaller pollen size, the range of variation among cultivars was low (means' range 51-66 μm).

CONTEXT. Campomanesia xanthocarpa Berg. (Myrtaceae), popularly known in Brazil as guabiroba, is a plant used as antidiarrheic, anti-inflammatory and antirheumatic agents, and in stomach and hepatic disorders.The antiproliferative and genotoxic effects of aqueous extracts and essential oil of C. xanthocarpa were evaluated.Cytotoxicity and genotoxicity of the aqueous extracts (6 and 30 mg/mL) and essential oil (0.25%, v/v) obtained from leaves of C. xanthocarpa were evaluated using the Allium cepa L. (Amaryllidaceae) assay. Mitotic index was calculated as the percentage of dividing cells of total cells observed; chromosome abnormalities were observed and counted during cell division. Additionally, the composition of the essential oil and the quantification of the main compounds of the extracts were determined by gas chromatography/mass spectrometry and high performance liquid chromatography coupled with diode array detector, respectively.Aqueous extracts (6 and 30 mg/mL) led to a reduction of 67.7% and 34.1% of the mitotic index, respectively, whereas the treatment with essential oil caused a 48.2% reduction in the mitotic index, when compared with negative control. Chromosomal mutations were observed and included anaphase bridges, delay chromosome, break chromosome, as well as metaphase with disorganized chromosomal and binuclear cells. The main compounds of the essential oil were β-caryophyllene (8.87%), viridiflorol (6.40%), spathulenol (5.16%), δ-cadinene (4.92%), linalool (4.46%) and α-cadinol (4.25%). Gallic acid (3.19%), chlorogenic acid (1.04%), quercetin (2.97%) and rutin (4.82%) were identified in an aqueous extract (30 mg/mL).Our results demonstrated that genotoxic and antiproliferative activities are present in C. xanthocarpa infusions using the in vivo onion root-tip cell test.

Biological assays are widely used to monitor toxic and allelopathic substances. The present study aimed to evaluate the allelopathic, genotoxic, and antiproliferative potential of aqueous extracts ...

The medicinal and tree species Luehea divaricata is known as ‘acoita-cavalo’ and widely used for wood, reclamation, and in popular medicine. The aim of this study was to evaluate the antiproliferative and genotoxic effects of infusions of two populations of this species on the Allium cepa cell cycle. Cells of root tips of Allium cepa were used as an in vivo test system for monitoring the genotoxicity of this medicinal plant. Leaves and bark of two populations of Luehea divaricata were collected during the vegetative stage and used to prepare infusions in two concentrations: for the leaves (6 g/L and 30 g/L) and two concentrations for the bark (32 g/L and 160 g/L), using distilled water as negative control and glyphosate 3% as positive control. For this study, 10 groups of four bulbs were utilized, with one group of bulbs for each treatment. The slides were prepared by the squashing technique, scoring 4000 cells for each group of bulbs. The mitotic index (MI) was calculated and then a statistical analysis ...

Hyptis mutabilis é uma espécie medicinal da família Lamiaceae que possui importante valor fitoterápico. Não há registros sobre estudos cromossômicos e comportamento meiótico nessa espécie em populações na região sul do Brasil. Cromossomos mitóticos, comportamento meiótico e viabilidade polínica foram estudados em populações de H. mutabilis do estado do Rio Grande do Sul, Brasil, usando coloração com orceína acética 2%. As populações apresentaram número cromossômico 2n = 28, sendo em algumas células encontrado 2n = 26 e 32 cromossomos, indicando a ocorrência de polissomatia. Ocorreram irregularidades no pareamento com associações univalentes, trivalentes, e tetravalentes, bem como presença de retardatários durante a disjunção. No entanto, os valores do índice meiótico e estimativa da viabilidade polínica foram altos, 71.19 a 92.34% e 83.25 a 96%, respectivamente.

Some species of Psychotria (Rubiaceae) are important in herbal medicine, where their extracts are used internally for infections of the female reproductive system, bronchitis, gastrointestinal disturbances, skin irritations, tumors, ulcers, and eye disturbances. The antiproliferative and genotoxic effects of Psychotria myriantha Mull. Arg. and P. leiocarpa Cham. et Schlecht infusions on the Allium cepa L. cell cycle were evaluated. The teas were prepared by infusing the leaves in distilled water, in two concentrations: 1.13 mg/mL and 6.78 mg/mL. Three groups of four bulbs were used for each Psychotria species. After the bulbs rooted in distilled water, they were transferred to the teas for 24 hours, except for the control that stayed in water. The rootlets were then collected, fixed in ethanol-acetic acid (3:1) for 24 hours, and stored in 70% ethanol. For each group of bulbs, 4000 cells were analyzed, calculating the mitotic indexes, submitting them to statistic analysis, using the χ 2 test (p = 0.05). The results showed a decrease in mitotic index with an increase in tea concentration in both species. In P. leiocarpa, the mitotic index values differed significantly between the control and concentration of 6.78 mg/mL (χ 2 = 9.863). For P. myriantha, the values referring to the mitotic index differed greatly between the control and the treatments (χ 2 = 124.8). With this study, it was determined that P. myriantha and P. leiocarpa infusions possess antiproliferative effects on the A. cepa cell cycle, and teas of P. myriantha also have genotoxic activity.

Bidens pilosa is a medicinal species from the Asteraceae family, with a wide geographical distribution, found all over Brazil. There are no reports on chromosomal studies from the Brazilian South. Mitotic chromosomes, meiotic behavior, and pollen viability were studied in 6 populations of B. pilosa from Rio Grande do Sul State, Brazil, using conventional staining with acetic orcein 2%. The populations include cytotypes with a variable number of chromosomes: 2n=36, 2n=48 and 2n=54, indicating polyploidy and aneuploidy. The meiotic process was considered regular, even though irregular chromosomal pairing appeared, which is normal in cytotypes from a polyploid complex. The irregularities observed were mainly on univalent, trivalent, and tetravalent pairing associations. However, the pollen viability estimative was high.

The species Citrus sinensis (L.) Osbeck (orange) is used in folk medicine as an infusion (tea) for the treatment of nerve irritation, insomnia, spasms, whooping cough, flue, and gastrointestinal problems. The aim of this study was to evaluate the antiproliferative and genotoxic potential of aqueous extracts of C. sinensis testing by Allium cepa L., as well as to determine the components in the complex mixture (tea). Leaves from two populations of this species were used in the preparation of infusions at two concentrations: 6g.L-1 and 24g.L-1, besides using distilled water as a negative control and 9.6% glyphosate as a positive control. Six groups of four bulbs of A. cepa were used, each group corresponding to one of the treatments. The bulbs were rooted in distilled water and then transferred to the respective treatments where they remained for 24 hours (the bulbs of the negative control remained in distilled water). The rootlets were collected, fixated in ethanol-acetic acid (3:1) for 24 hours and stored in 70% alcohol. 4,000 cells were analyzed per group of bulbs, and the calculated mitotic indices were submitted to statistical analysis using the c2 test. The aqueous extracts of C. sinensis have as main components flavonoids and phenolic acids. The values of the mitotic index decreased with increasing concentration of the extracts relative to the control in water. The results indicated that the orange aqueous extracts in the studied concentrations in both populations have antiproliferative and genotoxic effects on the cell cycle of A. cepa. The species Citrus sinensis (L.) Osbeck (orange) is used in folk medicine as an infusion (tea) for the treatment of nerve irritation, insomnia, spasms, whooping cough, flue, and gastrointestinal problems. The aim of this study was to evaluate the antiproliferative and genotoxic potential of aqueous extracts of C. sinensis testing by Allium cepa L., as well as to determine the components in the complex mixture (tea). Leaves from two populations of this species were used in the preparation of infusions at two concentrations: 6g.L-1 and 24g.L-1, besides using distilled water as a negative control and 9.6% glyphosate as a positive control. Six groups of four bulbs of A. cepa were used, each group corresponding to one of the treatments. The bulbs were rooted in distilled water and then transferred to the respective treatments where they remained for 24 hours (the bulbs of the negative control remained in distilled water). The rootlets were collected, fixated in ethanol-acetic acid (3:1) for 24 hours and stored in 70% alcohol. 4,000 cells were analyzed per group of bulbs, and the calculated mitotic indices were submitted to statistical analysis using the c2 test. The aqueous extracts of C. sinensis have as main components flavonoids and phenolic acids. The values of the mitotic index decreased with increasing concentration of the extracts relative to the control in water. The results indicated that the orange aqueous extracts in the studied concentrations in both populations have antiproliferative and genotoxic effects on the cell cycle of A. cepa.

In Brazil leaf infusions of the plant Pterocaulon polystachyum DC (Asteraceae) are used to treat digestive problems. We used plants from six P. polystachyum populations to prepare fresh aqueous leaf infusions at the concentration normally used in Brazil (2.5 g L-1) and at twice (5 g L-1) and four times (10 g L-1) this concentration. We rooted onion bulbs in a water control or one of the infusions for 24 h and used the in vivo onion (Allium cepa) root-tip cell test to investigate the potential mutagenicity of the infusions by calculating the mitotic index for the control and the experimental treatments and comparing them using the Chi-squared test (chi2, p = 0.05). There was a highly significant decrease in the mitotic index of root-tip cells treated with infusion as compared to those exposed to water only. These results indicate that P. polystachyum infusions present cytotoxic and anti-proliferative activity and therefore have therapeutic potential.

Polygala paniculata L. is a medicinal plant that grows in the Brazilian Atlantic coast, known as 'barba-de-Sao-Joao', 'barba-de-bode', 'vassourinha branca', and 'mimosa'. In this study, pollen viability was estimated by three different staining methods: 2% acetic orcein, 2% acetic carmine, and Alexander's stain. The young inflorescences of twenty accessions were collected and fixed in a solution of ethanol: acetic acid (3:1) for 24 hours, then stored in ethanol 70% under refrigeration. Six slides per plant, two for each stain, were prepared by squashing, and 300 pollen grains per slide were analyzed. Pollen viability was high (> 70%) for most accessions of P. paniculata using the Alexander's stain, which proved the most adequate method to estimate pollen viability.

The southern region of Brazil, especially Rio Grande do Sul State, is famous for its natural pastures. Many of the native legume species are potentially good forages. Among them are some of the 17 diploid (2n=20) species and one variety of Adesmia DC described for Brazil. Meiotic behaviour, meiotic indexes and pollen fertility were studied in 38 accessions of A. araujoi, A. arillata, A. bicolor, A. ciliata, A. incarta (including one tetraploid accession), A. latifolia, A. muricata, A. psoraleoides, A. punctata, A. reitziana, A. riograndensis, A. rocinhensis, A. securigerifolia, A. tristis and A. vallsii. For A. paranensis and A. sulina only pollen data were available. Meiotic behaviour was essentially regular in most of the accessions, with 10 bivalents (II) at diakinesis and metaphase I and regular chromosome segregation at anaphase and telophase I and II. Uni, tri and quadrivalents were sometimes observed at diakinesis and metaphase I as well as laggards and bridges at anaphase and telophase I a...

Species of the genus Psychotria are used for multiple purposes in Brazilian folk medicine, either as water infusions, baths or poultices. This study was aimed to evaluate the genotoxic and antiproliferative effects of infusions of Psychotria brachypoda and P. birotula on the Allium cepa test. Exposure to distilled water was used as a negative control, while exposure to glyphosate was used as a positive control. The interaction of extracts (as a post-treatment) with the effects of glyphosate was also studied. Results showed that glyphosate and the extracts of both P. brachypoda and P. birotula reduced the mitotic index as compared with the negative control (distilled water). Surprisingly, however, both extracts from P. brachypoda and P. birotula caused a partial reversal of the antiproliferative effect of glyphosate when used as a post-treatment. Glyphosate also induced the highest number of cells with chromosomal alterations, which was followed by that of P. birotula extracts. However, the extracts from P. brachypoda did not show any signifi cant genotoxic effect. Post-treatment of glyphosate-treated samples with distilled water allowed a partial recovery of the genotoxic effect of glyphosate, and some of the Psychotria extracts also did so. Notably, post-treatment of glyphosatetreated samples with P. brachypoda extracts induced a statistically signifi cant apoptotic effect. It is concluded that P. brachypoda extracts show antiproliferative effects and are not genotoxic, while extracts of P. birotula show a less potent antiproliferative effect and may induce chromosomal abnormalities. The fi nding of a partial reversion of the effects of glyphosate by a post-treatment with extracts from both plants should be followed up

Mode of reproduction was studied in 15 species of Adesmia DC. (Leguminosae). In six species, three treatments were used: mutual pollination, mechanical stimulation and control. Fifty-four plants of these six species were grown in a greenhouse, individually isolated in nylon screen boxes. Flowers were labelled and submitted to the different treatments. In addition, the frequency of spontaneous self-pollination in the absence of pollinators was studied in 200 plants of nine other species. These 200 plants were kept in a greenhouse, which avoided contact with any possible pollinator. Adesmia bicolor, A. muricata, A. punctata and A. riograndensis produced seed both by cross- and self-pollination. Adesmia punctata and A. riograndensis need mechanical stimulation for self-pollination. Adesmia incana reproduced by self-pollination; however, the possibility of cross-pollination cannot be totally ruled out. Adesmia tristis reproduced mainly by cross-pollination and a mechanism of self-incompatibility is suggested. Among the nine species that were not exposed to pollinators, A. securigerifolia produced a large amount of seed, indicating that it is a self-pollinating species. Adesmia arillata, A. araujoi, A. ciliata, A. psoraleoides, A. rocinhensis, A. reitziana, A. sulina and A. vallsii did not produce any seed under the experimental conditions, suggesting that they are cross-pollinated or that they need mechanical stimulation to reproduce.Foram estudadas 15 espécies do gênero Adesmia DC. (Leguminosae), quanto ao modo de reprodução. Em seis espécies do gênero Adesmia, o modo de reprodução foi determinado através de três tratamentos: polinização mútua, estímulo mecânico e controle. As 54 plantas submetidas aos tratamentos foram cultivadas em casa de vegetação e mantidas isoladas individualmente, através de armações de tela de náilon. As flores foram marcadas e submetidas aos distintos tratamentos. Adicionalmente, foram observadas 200 plantas de outras 9 espécies do mesmo gênero quanto à ocorrência de autofecundação na ausência de polinizadores. As 200 plantas apenas isoladas e observadas foram cultivadas em vasos e mantidas em casa de vegetação telada, sem acesso de polinizadores. Os resultados mostraram que, das espécies investigadas pelos três tratamentos, A. bicolor, A. muricata, A. punctata e A. riograndensis são versáteis, pois permitiram a reprodução por fecundação cruzada e autofecundação. As duas últimas, para se autofecundarem, necessitaram de estímulo mecânico. Adesmia incana se reproduziu por autofecundação, mas não se descarta a possibilidade de ocorrer fecundação cruzada. Adesmia tristis se reproduziu quase que totalmente por fecundação cruzada e é possível a ocorrência de mecanismos de autoincompatibilidade. Das nove espécies apenas observadas, Adesmia securigerifolia se reproduziu por autofecundação, formando elevado número de sementes por planta. A. arillata, A. araujoi, A. ciliata, A. psoraleoides, A. rocinhensis, A. reitziana, A. sulina e A. vallsii não produziram sementes por autofecundação espontânea. Estas espécies são de fecundação cruzada ou necessitam do estímulo do polinizador.

The species Conyza bonariensis, known as hairy fleabane, belongs to the Asteraceaefamily and has its origin in South America. It has an annual cycleof life, being prolific and able to produce up to 200,000 seeds per plant.It occurs in various climatic conditions, showing good adaptability, and isgenerally considered weed, but also used as medicinal. To help on the identificationof this species, the study aimed to perform cytogenetic characterization,starting from seeds collected of populations occurring in the higmediumplains region of Rio Grande do Sul. To determinate the numberof chromosomes, the seeds were germinated and the root-tips with 2-5 mmin length were collected and subjected to cold pretreatment (4°C) for 18h,fixed in ethanol: acetic acid (3:1) for 24h and kept in 70% ethanol underrefrigeration. For the preparation of slides, the root-tips were hydrolyzedin 2N HCl for 5 min and stained with acetic orcein (2%) by the squashingtechnique. The results were 2n = 36 chromosomes to populations of Juliode Castilhos, Tupancireta, Cruz Alta, Victor Graeff; and 2n = 5x = 45 for thepopulation of Nao-Me-Toque, morphologically corresponding to Conyza bonariensisvar. microcephala, except the population of Tupancireta, which it isConyza bonariensis var. bonariensis.

We evaluated the antiproliferative effect of infusions from Pluchea sagittalis using the Allium cepa test. Infusions in three concentrations (2.5, 5, and 25 g dm-3) of leaves cultivated in three environments (in vitro, acclimatized growth chamber, and field) were used. Six onion bulbs were used for each of the eight treatments, and the mitotic index was obtained from 6000 cells per treatment. In conclusion, leaf infusions of P. sagittalis cultivated in the field have a high antiproliferative activity, as well as the cultivation system influences the antiproliferative potential.Avaliou-se o efeito antiproliferativo de infusões de Pluchea sagittalis usando o teste de Allium cepa. Foram usadas infusões em três concentrações (2,5, 5 e 25g dm-3) de folhas cultivadas em três ambientes (in vitro, sala de crescimento climatizada e em campo). Foram usados seis grupos de bulbos para cada um dos 8 tratamentos e o os índices mitóticos foram obtidos a partir de 6000 células por tratamento. Concluiu-se que a infusão de folhas de P. sagittalis cultivadas em campo possui grande atividade antiproliferativa, bem como o sistema de cultivo de plantas influencia o potencial antiproliferativo.

Cytogenetic characterization was carried out on 12 accessions from Aster squamatus (Spreng.) Hieron., Pterocaulon polystachyum DC, and Solidago microglossa DC by studying their meiotic behavior and pollen viability. These species are from the Asteraceae family, native to Rio Grande do Sul State, Brazil, and are important for medicinal use. Young inflorescences with four accessions of each species were collected, fixed in ethanol-acetic acid (3:1), and conserved in ethanol 70% until use. The method used was that of squashing the anthers and coloring with acetic orcein 2%. Meiosis was regular in all accessions, presenting chromosomal associations preferentially bivalent, where n=10 was found for Aster squamatus and n=9 for Pterocaulon polystachyum, and Solidago microglossa. The studied accessions presented a Meiotic Index (MI) that varied from 65% to 87% in Aster squamatus, 85% to 92% in Pterocaulon polystachyum, and 64% to 92% in Solidago microglossa, indicating meiotic stability, although irregularities appeared during the cellular division. The pollen viability estimative was high in all studied accessions. These results indicate that the studied species can be included in future studies of genetic breeding. Foi realizada a caracterização citogenética de doze acessos de Aster squamatus, Pterocaulon polystachyum e Solidago microglossa, espécies da família Asteraceae, nativas do Rio Grande do Sul, Brasil, por meio do estudo do comportamento meiótico e da viabilidade polínica, que possuem grande importância para uso medicinal. Inflorescências jovens de quatro acessos de cada espécie foram fixadas em álcool-ácido acético (3:1) e conservadas em álcool 70% até o uso. O método utilizado foi o de esmagamento de anteras e a coloração com orceína acética 2%. A meiose foi regular em todos os acessos, apresentando associações cromossômicas preferencialmente em bivalentes, encontrando-se n=10 para Aster squamatus e n=9 para Pterocaulon polystachyum e Solidago microglossa. Os acessos apresentaram índice meiótico que variou de 65% a 87% em Aster squamatus, de 85% a 92% em Pterocaulon polystachyum e de 64% a 92% para Solidago microglossa, indicando estabilidade meiótica, apesar de o aparecimento de irregularidades durante a divisão celular. A estimativa da viabilidade polínica foi alta para todos os acessos estudados. Esses resultados indicam que as espécies estudadas podem ser incluídas em futuros trabalhos de melhoramento genético.

Mundialmente, muitas espécies de plantas medicinais são utilizadas para o tratamento de doenças. No entanto, a maioria dessas espécies não foram suficientemente estudadas, principalmente quanto à presença de substâncias citotóxicas/mutagênicas em sua composição ou decorrentes do próprio metabolismo e podem causar danos à saúde da população. A presença de substâncias mutagênicas nas espécies vegetais que causam alterações cromossômicas podem ser detectadas durante o ciclo celular de uma espécie. O sistema teste de Allium cepa é freqüentemente utilizado para avaliação do potencial genotóxico de extratos de plantas medicinais através da análise de células meristemáticas provenientes de pontas de raízes tratadas com infusões medicinais (chás). O conhecimento do potencial genotóxico destas espécies medicinais, através da análise do ciclo celular de Allium cepa serve como indicativo de segurança para a população que utiliza chás medicinais como única alternativa para o tratamento de doenças. Essa revisão, objetiva informar a respeito da importância do teste de Allium cepa para avaliação preliminar da genotoxicidade de infusões de plantas medicinais. All over the world, many species of medicinal plants are used for disease treatments. However, most of them were not deeply studied; and the presence of cytotoxic or mutagenic substances in their composition or resulting from their metabolism may be harmful to human beings. The mutagenic effects caused by such substances result in chromosomal changes which are detecTable during the cell cycle of a species through cytogenetic analysis. The Allium cepa test system is widely used for evaluating the genotoxic potential of infusions (tea) made of medicinal plants, through the cell cycle analysis. The knowledge of the genotoxic potential of such species through the Allium cepa test serves as a warning and safety bioindicator for the population who uses medicinal tea quite often as the unique alternative for disease treatment of its people. In the review article, we intend to inform people about the importance of the Allium cepa test for evaluating the genotoxicity of infusions of medicinal plants.

Este trabalho teve como objetivo o emprego de isolados antagonistas de fungos visando à promoção do enraizamento de microestacas de um clone de Eucalyptus sp. Utilizaram-se no teste de promoção de enraizamento de microestacas um isolado não-patogênico de Cylindrocladium spp. e mais três isolados antagonistas de Trichoderma spp. (E15, S2 e St), os quais apresentaram as melhores notas de antagonismo em teste in vitro, pelo método de confrontação direta contra isolado patogênico de Cylindrocladium spp., sendo inoculados no substrato de desenvolvimento das microestacas sob condições de estufa. Observou-se aumento de sobrevivência das microestacas na presença dos isolados de Trichoderma spp. e Cylindrocladium spp., em comparação com a testemunha, em ambiente naturalmente infestado por Botrytis cinerea. O tratamento com os isolados ST, E15 e S2 de Trichoderma spp. e Cyl de Cylindrocladium spp. aumentou a sobrevivência de microestacas de Eucalyptus sp. O isolado E15 promoveu o enraizamento de microestacas, apresentando aumento significativo na porcentagem de enraizamento (62,25%) em relação ao tratamento-testemunha (28,77%). The purpose of this research was to apply antagonistic isolates of fungi to induce microcutting rooting of an Eucalyptus sp. clone. One non-pathogenic isolate of Cylindrocladium spp. and three antagonistic isolates of Trichoderma spp (E15, S2 and St) were used for the microcutting rooting experiment. The latter gave better results in the antagonistic in vitro test using the method of direct confrontation against the pathogenic isolate of Cylindrocladium spp, being inoculated in the microcutting rooting substrate, in greenhouse conditions. Increase of microcutting survival was observed in the presence of isolates of Trichoderma spp. and Cylindrocladium spp. when compared with control in an environment naturally infested with Botrytis cinerea. The treatments with the isolates ST, E15 and S2 of Trichoderma spp. and Cyl of Cylindrocladium spp. increased the survival of Eucalyptus sp. microcuttings. The E15 isolate promoted a significant increase in the rooting percentage (62.25%) compared to the control treatment (28.77% ).

A caracterização citogenética das plantas medicinais de um país amplia as perspectivas da conservação da diversidade vegetal de espécies comumente utilizadas na medicina popular. Das espécies utilizadas medicinalmente no Brasil, algumas são nativas, dentre as quais se destaca, Achyrocline satureioides Lam. (marcela) da Família Asteraceae. Neste estudo, pela primeira vez, foi realizada a contagem do número cromossômico de populações de marcela, nativas do estado do Rio Grande do Sul. Foram coletadas sementes de cinco populações de marcela em seus locais de origem, as quais foram colocadas para germinar em ambiente controlado. Após a germinação, as pontas de raízes foram coletadas e pré-tratadas com paradiclorobenzeno durante cinco horas, fixadas em álcool absoluto:ácido acético glacial (3:1) por 24h a temperatura ambiente e, posteriormente, conservadas em álcool 70%, até o seu uso. A análise do número cromossômico foi feita a partir da confecção de lâminas das pontas das raízes, sendo que para o preparo das lâminas utilizou-se a técnica do esmagamento, hidrólise em HCl 5N por 10min, aplicação de ácido acético 45% durante 1min, esmagamento das pontas das raízes e coloração com orceína acética a 2%. Todas as populações estudadas apresentaram 2n=24 cromossomos, o que sugere ser esse o número diplóide da espécie. The cytogenetics of medicinal plants in a country enlarges the perspectives of conservation of the vegetal diversity of species generally used in popular medicine. Some of the species used medicinally in Brazil are native, and Achyrocline satureioides Lam. (marcela), from Asteraceae Family, is highlighted among them. In this study the first counting of the chromosomal number in marcela populations, which are native from Rio Grande do Sul State, was performed. Seeds of five populations of marcela were collected in their native local. Such seeds were put at room temperature to germinate. After germinating, the root-tips were collected and pre-treated with saturated solution of paradichlorobenzene for five hours, fixed in absolute ethanol glacial acetic acid (3:1) for 24 hours at room temperature and, after that, maintained in alcohol 70% until they were used. The analysis of the chromosomal number was performed with slides of root-tips by using the squashing technique, hydrolysis in HCI 5N for 10min, acetic acid application 45% for 1min, squashing of the root-tips and staining in orcein acetic 2%. All populations presented 2n=24 chromosomes, suggesting it as the probable diploid number of the species.

Um experimento foi conduzido em casa de vegetação, com plantas de um acesso de Adesmia latifolia, para fazer observações relativas ao seu modo de reprodução. As plantas foram isoladas individualmente e, após o florescimento, foram submetidas a três tratamentos: estímulo mecânico, cruzamentos manuais e isolamento. Os resultados indicaram versatilidade da espécie, a qual pode reproduzir-se por fecundação cruzada e por autofecundação. An experiment was carried out to study the reproduction mode of Adesmia latifolia. The experiment was conducted in greenhouse with plants of one access of this species. The plants after flowering were isolated individually and submitted to three treatments: mechanical stimulation, hand crossing and isolation. The results showed versatility of this species which could reproduce by cross-fertilization and self-fertilization.

Foi comparada a qualidade da forragem entre os acessos diplóides e tetraplóides africanos e tetraplóides brasileiros de Hemarthria altissima. O experimento foi conduzido em casa de vegetação na Universidade Federal de Santa Maria. Os resultados obtidos mostraram Digestibilidade in vitro da matéria orgânica satisfatória para os acessos tetraplóides africanos e brasileiros, sendo que os brasileiros tiveram teores de proteína bruta signifi-cativamente maiores que os africanos. O tetraplóide natural do Rio Grande do Sul apresentou maior nível de proteína bruta. This study evaluated the quality among african dipoloid, tetraploid and brazilian tetraploid accessions Hemarthria altissima, the Experiment was conducted in greenhouse at the Federal University of Santa Maria. Results suggested that in vitro organic matter digestibility was satisfactory for tetraploid brazilian and african accessions, crude protein volues obtained for brazilian accessions were significantly higher than the african accessions. The tetraploids from Rio Grande do Sul region presented higher crude protein level.

Achyrocline saturoides (marcela) is used in Brazilian folk medicine as a tea in the treatment of digestive and inflammatory diseases. The anti-proliferative effect of infusions of marcela on onion cell cycle was evaluated by using the inflorescences of recently collected marcela and after the storage for 30 months. Marcela inflorescences were collected for the infusion preparations in 2003 and in 2005 (used still fresh). We prepared the infusions at two concentrations 5.0 mg/mL (concentration used as tea) and 20 mg/mL. We used two groups of six onion bulbs for each population of marcela, and one group of bulbs of each population was withdrawn as a control group. All bulbs rooted in distilled water and after they were transferred to the extracts of marcela and they were kept there for 24 hours (control bulbs remained under water). The root tips were collected, after fixed in ethanol acetic acid (3:1) for 24 hours and, stored under alcohol 70%. A total of 6000 cells per group of bulbs was analyzed, and the mitotic indexes were calculated and undergone to statistical analysis by using c2 at 5%. The conclusions were that the infusions of marcela have anti-proliferative action on the cell cycle of onion and that this inhibitory action on the cell division increases according to the increase of the infusion concentration, after storage as well.