ABSTRACT The search for bioherbicides has been encouraged, and plants used in food or with bioactivity have been studied. Therefore, this article aimed to investigate the bioherbicidal potential of essential oils from Psidium cauliflorum and P. acidum through a plant toxicity bioassay using Lactuca sativa and Sorghum bicolor. The seeds were treated with essential oils of both species, along with control groups treated with distilled water, dichloromethane, and glyphosate. Germination percentage (GP), germination speed index (GSI), root growth (RG), shoot length (SL), mitotic index (MI), chromosomal alterations (CA), and nuclear alterations (NA) were evaluated. The major compound of the essential oil of P. cauliflorum was α-pinene, and of P. acidum were trans-caryophyllene, β-elemene, germacrene A, and α-copaene. The essential oils from both species exhibited phytotoxic effects. P. acidum oil inhibited sorghum RG and lettuce SL, while P. cauliflorum oil reduced GP, GSI, RG, and SL in both plants, indicating higher phytotoxicity than P. acidum and non-selective behavior. Cytotoxic investigations showed that both oils inhibited the MI. CA analysis revealed that P. cauliflorum oil exhibited aneugenic and clastogenic action mechanisms. The results demonstrate the bioherbicidal potential of P. cauliflorum essential oil, in addition to being non-selective and displaying a similar inhibition rate to glyphosate.

The control of fungal species in agriculture is mainly conducted with the use of contact or systemic fungicides. However, environmental and human health concerns and increased resistance of fungal species to existing fungicides have increased the pressure on researchers to find new active ingredients for fungal control which present low toxicity to non-target organisms, are environmentally safe, and can be applied at very low concentrations. It is herein described the synthesis of eleven glycerol triazole containing compounds (ten of them fluorinated derivatives) and evaluation of their fungicidal activity. Eight out of eleven synthesized compounds are novel and all of the glycerol derivatives were characterized using infrared (IR), nuclear magnetic ressonance (NMR), and mass spectrometry (MS) techniques. Theoretical calculations were also carried out and the results are discussed. Starting from glycerol, the triazole derivatives were prepared in four steps. Evaluation of them against Colletrotricum gloesporioides showed that compound 1-((2,2-dimethyl-1,3 dioxolan-4-yl)methyl)-4-(2-fluorophenyl)-1H-1,2,3-triazole (4d) (ED50 = 59.14 µg mL-1) was slightly more active than commercial fungicide tebuconazole (61.35 µg mL-1). Compound 4d presented attractive physicochemical features for agrochemical purposes as revealed by the calculated physicochemical parameters. It is believed that glycerol-fluorinated triazole derivatives can be explored towards the development of new chemicals for the control of fungal species.

Resumo Investigar a diversidade genética em populações naturais de espécies com potencial para uso em programas de reflorestamento é um passo importante para a tomada de decisões relacionadas ao planejamento e manejo dos plantios. No entanto, programas de reflorestamento com espécies nativas no Brasil raramente são realizados com base no conhecimento do genótipo das matrizes doadoras das sementes utilizadas para produção de mudas. Este é o caso de Myrsine umbellata, um arbusto dioico pertencente à família Primulaceae, que vem sendo utilizado em programas de reflorestamento no Brasil principalmente por apresentar elevada capacidade de produção de frutos atrativos à avifauna. O objetivo deste estudo foi mensurar a diversidade genética intra e interpopulacional em populações naturais de M. umbellata em seis remanescentes florestais da Floresta Atlântica, utilizando marcadores ISSR. Os resultados revelaram que a diversidade genética intrapopulacional foi maior que a diversidade genética entre as populações estudadas. Por essa razão, o cultivo de mudas a partir de sementes obtidas em mais de uma população parece ser a estratégia mais apropriada para reflorestamento. Mesmo considerando que as populações mais isoladas são aquelas mais estruturadas, todas as populações de M. umbellata incluídas neste estudo revelaram ser importantes bancos de germoplasma conservados in situ.

Abstract The investigation of genetic diversity in natural populations of species that show potential for use in reforestation programs is a key step in making management decisions. However, reforestation programs with native species in Brazil are still rarely based on a genetic understanding of the seed matrices used for seedling production. This is also the case for Myrsine umbellata, a dioecious shrub within the family Primulaceae that has been used in reforestation programs in Brazil, mainly due to its high production capacity of fruits attractive to the avifauna. The goal of this study was to measure intra- and interpopulational genetic diversity in natural populations of M. umbellata in six forest remnants of the Atlantic Forest using ISSR markers. The results revealed that the intrapopulational genetic diversity was greater than the genetic diversity among the studied populations. For this reason, the cultivation of seedlings from seeds obtained in more than one population seems the most appropriate strategy for reforestation purposes. Even though the most isolated populations are also the ones with highest genetic structure, all populations of M. umbellata included in this study revealed to be an important germplasm bank conserved in situ.

Resumo Espécies de plantas que mostram padrão gregário de distribuição e endemismo na Floresta Atlântica, como Dorstenia elata, são particularmente sensíveis aos efeitos da perda da diversidade genética. Considerando isso, objetivou-se com este trabalho quantificar a diversidade genética em populações nativas dessa espécie em um remanescente da Mata Atlântica. A amostra incluiu três subpopulações de indivíduos e a caracterização molecular foi realizada com doze primers ISSR. As análises intrapopulacionais foram baseadas no cálculo do índice de Shannon; a heterozigosidade total esperada e a matriz de distâncias entre pares de indivíduos também foram calculadas. O dendrograma de agrupamento obtido evidenciou a formação de dois grupos. As investigações interpopulacionais foram baseadas na análise de variância molecular e na estimativa do fluxo gênico. Os resultados demonstram que um grupo compreendeu os genótipos de duas subpopulações, e o outro continha exclusivamente os genótipos de uma terceira subpopulação. A maior variabilidade genética foi observada dentro e não entre populações, indicando que a distância geográfica e a estrada que divide as populações estudadas não estão causando perda de diversidade genética.

Abstract Plant species that show gregarious spatial distribution and endemism to the Atlantic Forest, such as Dorstenia elata, are particularly sensitive to the effects of genetic diversity loss. In the present study, we aimed to quantify the genetic diversity in native populations of this species in an Atlantic Forest remnant. The sample included three aggregates of individuals, and molecular characterization was performed with twelve ISSR primers. Intrapopulation analyses were based on the calculation of the Shannon index; total expected heterozygosity and the matrix of distances between pairs of individuals were also calculated. The obtained grouping dendrogram evinced the formation of two groups. Interpopulation investigations were based on the analysis of molecular variance and the estimate of historical gene flow. The results demonstrate that one group comprised the genotypes from two subpopulations, and the other contained exclusively the genotypes of a third subpopulation. The greatest genetic variability was observed within rather than among populations, indicating that the geographical distance and the road that divides the studied populations are not causing loss of genetic diversity.

ABSTRACT The Atlantic Forest is a biome that has suffered anthropic actions, such as the extraction of hardwood, which can lead to the extinction of endemic species of great economic and ecological value, such as Dalbergia nigra. In this perspective, large-scale multiplication studies are necessary to contribute to the conservation of this species. The objective of this work was to establish a protocol for the in vitro production of axenic seedlings of D. nigra. Four experiments were performed: I. Immersion times in NaOCl. II. Disinfecting agents in seed germination of D. nigra. III. NaOCl toxicity in seeds of the model species Lactuca sativa L. IV. Culture media and glutamine in the germination and initial growth of D. nigra. All experiments were arranged in a completely randomized design. For a better disinfestation and less harmful effects to the seedlings, it is recommended that the seeds be treated with 70% alcohol (1 min) and NaOCl (14 min). NaOCl has a high phytotoxic, cytotoxic, and genotoxic effect, and its mechanism of action in the L. sativa cell cycle is clastogenic and aneugenic, suggesting the formation of abnormal seedlings in D. nigra. The WPM medium and its supplementation with glutamine (0.75 mg.L-1) are recommended.

Resumo Neste trabalho são apresentadas as espécies de Passifloraceae sensu stricto do estado do Espírito Santo, Brasil. A família encontra-se representada por dois gêneros, Mitostemma, com apenas M. glaziovii e Passiflora com 30 espécies, com representantes de quatro subgêneros: duas espécies pertencentes ao subgênero Astrophea, seis ao subgênero Debaloba, uma ao subgênero Deidamioides, e vinte e um ao subgênero Passiflora. Dentre as espécies, P. margaritae é classificada como “em perigo” (EN), de acordo com os critérios da IUCN, e temos o primeiro registro de P. cacao e P. campanulata para o estado. São apresentadas descrições, dados de distribuição geográfica e comentários.

Abstract A treatment of the species of Passifloraceae sensu stricto from the state of Espírito Santo, Brazil is presented. The family is represented by two genera: Mitostemma, with M. glaziovii, and Passiflora with 30 species in four subgenera: two species belonging to subgenus Astrophea, six to subgenus Decaloba, one to subgenus Deidamioides, and twenty one to subgenus Passiflora. Among the species, we highlight P. margaritae, considered endangered (EN), according to the IUCN, and we record the first occurrence of P. cacao and P. campanulata for the state. Descriptions, photos, distribution data and taxonomic comments regarding the species are presented.

ABSTRACT The development of tissue cultured-based protocols applied to braúna, an endangeres species, would be though highly desirable. However, contamination-free explants are determinant for the success of this technique, which might be vulnerable to the toxicity of disinfectants. Here, we aimed at establishing an efficient protocol for in vitro production of axenic seedlings of braúna and to evaluate the toxicity of disinfectant agents in the Lactuca sativa model species. Experiments I and II: Seeds were treated with sodium hypochlorite (NaOCl) and fungicide captan, with and without residue, by different immersion times, respectively. The following were analyzed: contamination; germination and normal and abnormal seedlings. Experiment III: Lettuce seeds placed in Petri dishes were exposed to 2.5 mL captan at 0.5; 1; 2; 4 and 8%; 0.01% glyphosate and distilled water. The germination, length of seedlings, cell cycle, nuclear and chromosomal alterations of the cells of the root meristem were assesed. The isolated use of NaOCl was not efficient in the disinfestation of braúna seeds. However, the immersion of the seeds in captan, for 10 minutes with its residue, led to higher germination and vigor indexes; however, resulted in the formation of abnormal seedlings. This compound exhibited toxicity in the lettuce model seeds because affected the germination and the whole development of the seedlings, showing clastogenic and aneugenic action in the meristematic cell cycle.

Resumen Jatropha curcas L., naturalizado tropical y subtropical, ha sido explorado para la producción de biodiesel. El aceite se extrae de las semillas y, para que la producción sea factible, la utilización de la torta de semillas residual es crucial. Aunque la torta se puede emplear como una fuente de proteína en la alimentación animal, es rica en éster de forbol, que es tóxico para los animales. Por lo tanto, los programas de mejoramiento han procurado reducir o eliminar el contenido de éster de forbol de J. curcas. En este contexto, el presente trabajo tuvo como objetivo evaluar el aceite de J. curcas de las variedades tóxicas y no tóxicas (con cantidades conocidas o indetectables de éster de forbol, respectivamente) con respecto a la fitotoxicidad en el modelo Lactuca sativa L. El porcentaje de semillas germinadas se evaluó después de 8, 16, 24, 36 y 48 horas de tratamiento. El crecimiento de la raíz se determinó después de 48 horas de exposición y se obtuvo el índice de velocidad de germinación. Se registraron las diferentes etapas de la división mitótica así como posibles alteraciones cromosómicas y nucleares. El índice mitótico se calculó como el número de células en división como una fracción del número total de células y la frecuencia de las alteraciones cromosómicas y nucleares, expresada como el porcentaje del número de alteraciones dividido entre el número total de células. Ambas variedades exhibieron fitotoxicidad, induciendo reducciones significativas en el porcentaje de semillas germinadas (Reducción del 98 %), índice de velocidad de germinación (Reducción de 24.44) y crecimiento de raíces (Reducción de 8.54 mm). En el análisis microscópico, se observó un efecto mitodepresivo para ambos aceites. Sin embargo, fue posible distinguir entre las variedades tóxicas y las no tóxicas basándose en la reducción más expresiva de la división promovida por la primera, 2.19 %. Se observaron incrementos significativos en la frecuencia de células mitóticas que mostraban alteraciones cromosómicas, así como la presencia de núcleos condensados en las células tratadas. Sin embargo, estos parámetros no fueron significativamente diferentes del control en las células tratadas con ambos aceites de J. curcas. En conclusión, la evaluación del crecimiento de las raíces y la división celular en el modelo L. sativa se puede proponer como una alternativa a las pruebas en animales para distinguir las variedades con concentraciones altas y bajas de éster de forbol, contribuyendo así a la detección de toxicidad en variedades utilizadas en programas de mejoramiento genético.

Abstract The tropical and subtropical naturalized physic nut (Jatropha curcas L.), has been explored for biodiesel production in recent times. The oil is extracted from the seeds and, for the production to be feasible, utilization of the residual seed cake is crucial. Although the cake could be employed as a protein source in animal feed, it is rich in phorbol ester, which is toxic for animals. Therefore, breeding programs have been working to reduce or eliminate the phorbol ester content in physic nut. In this context, the present work aimed to evaluate the physic nut oil of toxic and non-toxic varieties (containing known or undetectable amounts of phorbol ester, respectively) with regards to phytotoxicity in a model experiment with Lactuca sativa L. For this, the percentage of germinated seeds was evaluated after 8, 16, 24, 36 and 48 hours of exposure to the treatments with toxic and non-toxic oil at concentrations of 22.5 %, 45 % and 67.5 % of emulsion (physic nut oil energetically mixed with distilled water). Root growth was determined after 48 hours of exposure and the germination speed index was obtained. The different stages of mitotic division as well as possible chromosomal and nuclear alterations were also recorded. The mitotic index was calculated as the number of dividing cells, as a fraction of the total number of cells, and the frequency of chromosome and nuclear alterations, expressed as the percentage of number of alterations divided by the total number of cells. Both varieties exhibited phytotoxicity, inducing significant reductions in percentage of germinated seeds (reduction of 98 %), germination speed index (reduction of 24.44) and root growth (reduction of 8.54 mm). In microscopic analysis, a mitodepressive effect was observed for both oils at the three concentrations used when compared to the negative control; however, it was possible to distinguish between the toxic and the non-toxic varieties based on the more expressive reduction of division promoted by the first, 2.19 %. Significant increments in the frequency of mitotic cells showing chromosome alterations as well, as the presence of condensed nuclei, were observed in the treated cells. However, these parameters were not significantly different from the control in the cells treated with both physic nut oils. In conclusion, the evaluation of root growth and cell division in the plant model L. sativa, can be proposed as an alternative to animal tests to distinguish the varieties with high and low phorbol ester concentration, thus contributing to the detection of toxicity in varieties used in breeding programs.