RESUMO: Pogostemon cablin (Blanco) Benth. é uma espécie aromática popularmente conhecida como patchouli. O óleo essencial rico em patchoulol extraído de folhas é utilizado pelas indústrias farmacêuticas. O objetivo foi investigar os efeitos das malhas e intensidades de sombreamento no crescimento, anatomia, composição química e teor de óleo essencial de P. cablin. O experimento foi conduzido com dois tipos de malhas (preta e Aluminet), três intensidades de luz (30, 50 e 70% de sombreamento) e pleno sol. As diferentes intensidades de luz influenciaram o crescimento, o rendimento e a composição química do óleo essencial. Plantas de patchouli cultivadas em ambiente sombreado apresentaram maiores valores para os pesos secos de folha, caule, raiz e total em relação ao pleno sol. Com 50% de sombreamento, Aluminet proporcionou ganho de peso seco de caule e total. Aluminet e malha preta a 50 e 70% de sombreamento aumentam o rendimento do óleo essencial. Os teores de patchoulol e pogostol foram maiores a pleno sol, malha preta e Aluminet com 50% de sombreamento. O ambiente para o cultivo do patchouli pode ser melhorado com o uso de malhas de sombreamento, especialmente com Aluminet em 50% de sombreamento.

ABSTRACT: Pogostemon cablin (Blanco) Benth. is an aromatic species popularly known as patchouli. The essential oil rich in patchoulol extracted from leaves is used by the pharmaceutical industries. The objective was to investigate the effects of shade nets and shading intensities on P. cablin growth, anatomy, chemical composition and essential oil content. The experiment was conducted with two types of shade nets (black and Aluminet), three light intensities (30, 50, and 70% shading) and full sun. The different light intensities influenced the growth and the essential oil yield, and chemical composition. Patchouli plants grown in an environment with shading showed higher values for the leaf, stem, root ant total dry weights compared to full sun. At 50% of shading, Aluminet provided gain in stem and total dry weights. Aluminet and black net at 50 and 70% of shading enhance essential oil yield. Patchoulol and pogostol contents were higher under full sun, and, black net and Aluminet at 50% shading. The environment for patchouli cultivation can be improved by use shade nets, especially with Aluminet at 50% of shading.

Resumo O objetivo deste trabalho foi avaliar a indução de organogênese indireta por concentrações de ácido diclorofenoxiacético (2,4-D) e tidiazurom (TDZ) em explantes de pitaia (Hylocereus undatus), por meio de microscopia eletrônica de varredura e da técnica de citometria de fluxo. Os tratamentos consistiram das concentrações de 0, 2,0 e 4,0 mg L-1 de 2,4-D e TDZ e das combinações desses reguladores. Avaliaram-se as percentagens de cobertura de calos aos 45 e 60 dias. Os explantes submetidos aos tratamentos foram analizados por citometria de fluxo e microscopia eletrônica de varredura. Todos os tratamentos induziram endorreduplicação, e não houve variação somaclonal. Na combinação de 2,0 mg L-1 TDZ e 4,0 mg L-1 2,4-D, calos foram formados em 95% dos explantes, mas foram menores do que os produzidos com 2,4-D separadamente. A concentração de 2,0 mg L-1 de TDZ induz organogênese indireta em explantes de pitaia, comprovada pela presença de vasos condutores por meio da microscopia eletrônica de varredura.

Abstract The objective of this work was to evaluate the induction of indirect organogenesis by concentrations of dichlorophenoxyacetic acid (2,4-D) and thidiazuron (TDZ) in pitaya (Hylocereus undatus) explants, using scanning electron microscopy and the flow cytometry technique. The treatments consisted of the concentrations of 0, 2.0, and 4.0 mg L-1 2,4-D and TDZ and of the combinations of these regulators. Percentages of callus coverage at 45 and 60 days were evaluated. The explants subjected to the treatments were analized by flow cytometry and scanning electron microscopy. All treatments induced endoreduplication, and there was no somaclonal variation. Under the combination of 2.0 mg L-1 TDZ and 4.0 mg L-1 2,4-D, calluses were formed in 95% of the explants, but were smaller than those produced with 2,4-D separately. The concentration of 2.0 mg L-1 TDZ induces the indirect organogenesis in pitaya explants, confirmed by the presence of conducting vessels through scanning electron microscopy.

RESUMO: O estudo teve como objetivo avaliar a influência da sazonalidade na composição química do óleo essencial (OE) de Mentha x piperita L. e Mentha viridis L. cultivadas no sudeste do Brasil. As folhas foram coletadas de novembro de 2011 até agosto de 2013, em meados das seguintes estações: primavera (novembro), verão (fevereiro), outono (maio) e inverno (agosto). A extração do OE foi realizada por hidrodestilação em aparelho de Clevenger por uma hora. A composição química do EO foi analisada por GC-FID and GC-MS. O teor de OE e sua composição química foram influenciados pela sazonalidade em ambas as espécies. O maior teor de OE foi obtido para M. x piperita na primavera (4,26%) e para M. viridis na primavera (3,30%) e verão (3,70%). Mentha x piperita aumentou o conteúdo de mentol (16,31 a 41,26%), neomentol (3,02 a 6,39%) e mentona (5,56 a 41,58%) durante a primavera e o verão, respectivamente. Já o conteúdo de OE de M. viridis não apresentou padrão de resposta de qualidade em relação à sazonalidade. Portanto, a colheita para M. x piperita é recomendada durante a primavera, e para M. viridis é recomendada durante a primavera e verão.

ABSTRACT: This study evaluated the influence of seasonality in essential oil (EO) chemical composition of Mentha x piperita L. and Mentha viridis L. grown in southeast of Brazil. Leaves were collected from November 2011 until August 2013, in the middle of the following seasons: Spring (November), Summer (February), Autumn (May) and Winter (August). EO extraction was carried out by hydrodistillation in Clevenger apparatus for 1 hour. Chemical composition of EO was analyzed by GC-FID and GC-MS. The EO content and its chemical composition were influenced by seasonality in both species. The highest EO content was obtained for M. x piperita during spring (4.26%) and for M. viridis during spring (3.30%) and summer (3.70%). Mentha x piperita increased menthol (16.31 to 41.26%), neomenthol (3.02 to 6.39%) and menthone (5.56 to 41.58%) contents during spring and summer, respectively. Whereas, M. viridis EO content did not show a quality response pattern in relation to seasonality. Therefore, harvest time for M. x piperita is recommended during spring, and for M. viridis is recommended during spring and summer.

RESUMO objetivou-se com o presente trabalho avaliar diferentes concentrações de duas citocininas na propagação in vitro da planta medicinal Hyptis marrubioides Epl. e analisar a fração volátil dos compostos. Segmentos nodais de plantas foram inoculados em meio sólido de Murashige e Skoog (MS) com diferentes concentrações de benzilaminopurina (BAP) ou tidiazuron (TDZ) sob 16/8-h luz/escuro em 25±2 ºC. Aos 45 dias de cultivo, as plantas foram avaliadas quanto ao número e comprimento de brotações e matéria seca da parte aérea. As análises dos constituintes voláteis foram por headspace-CG/EM. O maior número de brotos foi obtido com 1,0 mg L-1 de TDZ no meio MS. Os maiores valores para comprimento e matéria seca foram obtidos com BAP. Vinte e sete compostos foram caracterizados como constituintes de H. marrubioides óleo. Os compostos majoritários da fração volátil foram sabineno, α-tujona, β-tujona, α-copaeno, β-cariofileno, γ-gurjuneno e γ-himachaleno. Os tipos e as concentrações dos reguladores de crescimento afetaram o acúmulo da fração volátil. Mudanças quantitativas na classe dos monoterpenos e sesquiterpenos na fração volátil das plantas, também foram observadas em resposta do efeito do tipo de regulador de crescimento suplementado ao meio de cultura.

ABSTRACT The aim of this study was to evaluate different concentrations of two cytokinins in the in vitro propagation of the medicinal plant Hyptis marrubioides Epl. and to analyse the volatile fraction of the compounds. Nodal segments of plants were inoculated onto Murashige and Skoog (MS) solid medium with different concentrations of benzylaminopurine (BAP) or tidiazuron (TDZ) under a 16/8 h light/dark cycle at 25 ± 2 °C. After 45 days growth, the plants were evaluated for the number and length of the shoots and for shoot dry matter. The volatile constituents were analysed by headspace-GC/MS. The greatest number of shoots was obtained with 1.0 mg L-1 TDZ in the MS medium. The greatest values for shoot length and dry matter were obtained with BAP. Twenty-seven compounds were characterised as constituents of the essential oil of H. marrubioides. The major compounds of the volatile fraction were sabinene, α-thujone, β- thujone, α-copaene, β-caryophyllene, γ-gurjunene and γ-himachalene. The types and concentrations of the growth regulators influenced accumulation of the volatile fraction. Quantitative changes in the monoterpenes and sesquiterpenes in the volatile fraction of the plants were also seen in response to the type of growth regulator added to the culture medium.

RESUMO Objetivou-se com o presente trabalho estabelecer a micropropagação para Chenopodium ambrosioides L. e análise de constituintes voláteis in vitro em função de diferentes concentrações de sais do meio MS e de sacarose. As gemas apicais foram estabelecidas em meio MS acrescido de 3% de sacarose. O crescimento vegetativo dos segmentos nodais foi testado em diferentes concentrações de sais do meio básico MS (0,25; 0,50; 1,00; 1,50 e 2,00) e de sacarose (5; 10; 20; 30 e 40 g L-1). Segmentos nodais e apicais foram testados nas orientações vertical e horizontal. Diferentes volumes de meio de cultura (20; 35; 50; 65 e 80 mL) foram examinados no crescimento de segmentos nodais. As plantas foram aclimatizadas em três diferentes substratos. Os segmentos apicais coletados de plantas matrizes obtiveram sucesso ao estabelecerem-se em meio MS. Uma taxa de multiplicação de 8,5 foi obtida com segmento nodal e apical sem a utilização de regulador de crescimento. O meio MS com sua concentração de sais reduzida pela metade (0,50 MS) e a sacarose na concentração de 30 g L-1 proporcionaram melhor crescimento in vitro de segmentos nodais. Quatro principais compostos voláteis (α-terpineno, p-cimeno, Z-ascaridol e E-ascaridol) variaram nas diferentes concentrações de sais e para as concentrações de sacarose, apenas o α-terpineno apresentou diferença. Segmentos apicais na orientação vertical e segmentos nodais na horizontal, com 50 mL de meio de cultura, apresentaram melhores respostas para o cultivo in vitro de C. ambrosioides L.

ABSTRACT The aims of this study were to establish micropropagation for Chenopodium ambrosioides L. and analysis of volatile constituents in vitro as a function of different salt concentrations of MS medium and sucrose. The apical buds were established on MS medium added with 3% sucrose. The vegetative growth of nodal segments was tested in different salt concentrations of MS basic medium (0.25, 0.50, 1.00, 1.50, and 2.00) and of sucrose (5, 10, 20, 30, and 40 g L-1). Nodal and apical segments were tested in vertical and horizontal orientations. Different volumes of culture medium (20; 35, 50, 65, and 80 mL) were examined in the growth of nodal segments. Plants were acclimatized in three different substrates. The apical segments collected from matrices plants were successful when established in MS medium. A multiplication rate of 8.5 was obtained with nodal and apical segments without using growth regulator. MS medium with its salt concentration reduced by half (0.50 MS) and sucrose at the concentration of 30 g L-1 provided better in vitro growth of nodal segments. Four major volatile compounds (α-terpinene, p-cymene, Z-ascaridole, and E-ascaridole) varied at different salt concentrations and only α-terpinene showed difference for sucrose concentrations. Apical segments in vertical orientation and nodal segments in horizontal with 50 mL of culture medium showed better responses for the in vitro cultivation of C. ambrosioides L.

RESUMO. Objetivou-se avaliar a influência do cultivo consorciado de melissa com mil folhas, no crescimento vegetativo, teores de pigmentos fotossintéticos e de óleos essenciais e composição química de óleos essenciais. Para isso, foram comparados os cultivos solteiros de melissa e de mil-folhas com o cultivo consorciado de ambas. As plantas foram cultivadas por 120 dias em condições de campo. O delineamento experimental foi em blocos casualizados com sete repetições. O crescimento foi avaliado através do acúmulo de matéria seca da parte aérea e pela área foliar. Os teores de pigmentos fotossintéticos foram determinados a partir de folhas completamente expandidas de cinco plantas de cada tratamento. O óleo essencial foi extraído por hidrodestilação das folhas de melissa e de folíolos de mil folhas desidratados em estufa com ventilação forçada a 40°C. As análises químicas dos óleos essenciais foram realizadas por CG-DIC e CG-EM. O cultivo consorciado indicou redução no crescimento vegetativo, mas aumentou o teor de óleo essencial da melissa. Por outro lado, esses parâmetros não foram alterados para a mil-folhas. Houve variações nos teores dos constituintes químicos de ambos os óleos essenciais, que foram mais evidentes nos constituintes majoritários.

ABSTRACT. The purpose of this study was to assess the influence of lemon balm intercropping with yarrow on the vegetative growth, photosynthetic pigments and essential oil contents as well as the chemical composition of essential oils. Accordingly, the lemon balm and yarrow monocroppings were compared to the intercropping of both species. The plants were cultivated for 120 days under field conditions. The experimental design followed randomized blocks with seven repetitions. Growth was assessed through the accumulation of shoot dry matter and through the leaf area. The photosynthetic pigment content was set based on the fully expanded leaves from five plants in each treatment. The essential oil was extracted through the hydrodistillation of the lemon balm leaves and yarrow leaflets dehydrated in a forced ventilation oven at 40°C. The chemical analyses of the essential oils were performed using GC-FID and GC-MS. Intercropping showed a reduction of vegetative growth. However, intercropping increased the lemon balm essential oil content. On the other hand, these parameters did not change in yarrow. There were variations in the level of chemical constituents in lemon balm and yarrow essential oils, which were more evident in the major constituents.

ABSTRACT The aim of this study was to assess the sperm quality and testicular histomorphometry of Wistar rats supplemented with extract and fractions of fruits of Tribulus terrestris L. The ethanolic extract was obtained by dynamic maceration of spray-dried fruit. This extract was fractionated by liquid-liquid partition, using increasing polarity solvents. Twenty male rats were separated in four groups, with five rats in each group. The control was supplemented with distilled water, while the others were daily given the ethanolic extract, hexanic or aqueous fraction soluble in methanol in a dose of 42 mg.kg-1.day-1 for 70 days. Sperm was obtained from the right epididymal tail for the analysis of motility, count, morphology and viability. The testicular weight of groups supplemented with ethanolic extract and aqueous fraction soluble in methanol was higher when compared to the control. The gonadosomatic index increased in the group supplemented with ethanolic extract. The nuclear, cytoplasmic and individual volume of Leydig cells increased in supplementation with hexanic and aqueous fractions soluble in methanol. It was concluded that the extract influenced the spermatogenesis, while hexanic and aqueous fractions soluble in methanol promoted the changes in the intertubular compartment. Therefore, Tribulus terrestris did not improve the sperm quality of the rats.

A eficácia do óleo essencial de Ocimum selloi na inibição do crescimento micelial e na germinação de esporos foi avaliada in vitro para os fungos Moniliophthora perniciosa, Colletotrichum gloesporioides e Alternaria alternata. Seis constituintes (99,89%) do total do óleo foram identificados por CG-EM metil chavicol, metil eugenol, β-cariofileno, germacreno-D, biclogermacreno e espatulenol. O óleo essencial foi testado para atividade antifúngica, o qual foi determinado pelos métodos de difusão e concentração mínima inibitória (MIC). A aplicação do óleo reduziu o crescimento micelial dependente da dose, com máxima inibição na concentração de 1.000 ppm. A atividade antifúngica pode ser atribuída ao composto puro metil chavicol. Este mostrou ser efetivo contra M. perniciosaem 1.000 ppm. O óleo quando aplicado na concentração de 1.000 ppm, reduziu a germinação do esporo de Colletotrichum gloeosporioides e M. perniciosa em 93 e 87%, respectivamente, mas não teve efeito em Alternaria alternata. Conclui-se que o óleo essencial e seu constituinte majoritário, metil chavicol, são eficientes na inibição de M. perniciosa, mas menos efetivo contra C. gloeosporioides e A. alternata. Os resultados obtidos nesta pesquisa pode contribuir para o desenvolvimento de um agente alternativo para proteger a cultura do cacao contra esta doença fúngica.

The efficacy of Ocimum selloi essential oil was evaluated for controlling the growth of mycelia and spores germination Moniliophthora perniciosa. Six compounds (99.89%) of the total oil were identified by GC-MS, of which methyl chavicol, methyl eugenol, β-caryophyllene, germacrene-D, bicyclogermacrene and spathulenol. Essential oil was tested for antifungal activity, which was determined by disc diffusion and minimum inhibitory concentration (MIC) determination methods. Application of the oil reduced mycelial growth in a dose dependent manner, with maximum inhibition being observed at concentration of 1,000 ppm. Such antifungal activity could be attributed to methyl chavicol since the pure compound was shown to be similarly effective against Moniliophthora perniciosa at 1,000 ppm. The oil when applied at a concentration of 1,000 ppm, reduced the spore germination of Colletotrichum gloeosporioides and M. perniciosa by 93 and 87%, respectively, but had no effect on the Alternaria alternata. It is concluded that the oil from O. selloi and its major constituent, methyl chavicol, are efficient in inhibiting M. perniciosa, but less effective against C. gloeosporioides and A. alternata. The results obtained from this work may contribute to the development of alternative anti-fungal agents to protect the cacao crop from fungal disease.

Atroveran (Ocimum selloi Benth. - Lamiaceae) é uma espécie medicinal, usada para distúrbios digestivos e tratamento de inflamações. O objetivo deste trabalho foi avaliar o estabelecimento de segmentos nodais, germinação e crescimento, in vitro, de plântulas de atroveran, em diferentes concentrações de sacarose do meio MS e a aclimatização de plântulas em diferentes substratos. Para o estabelecimento e crescimento, utilizaram-se três concentrações do meio de cultura (MS, 1/2MS e 1/4MS) e duas concentrações de sacarose (15 g/L, 30 g/L e o controle). Para a germinação, as variações do meio de cultura foram: MS, 1/2MS, 1/4MS e 0MS (controle) e duas concentrações de sacarose (15 g/L, 30 g/L e o controle). Para a aclimatização, avaliaram-se os substratos: areia fina lavada, substrato comercial, solo e solo+esterco bovino (2:1). O uso de sacarose foi essencial para o estabelecimento e crescimento dos segmentos nodais de atroveran. Recomendam-se, assim, 15 g/L de açúcar. O 1/2MS é o mais indicado para o estabelecimento dos explantes e, o 1/4MS, para o crescimento de segmentos nodais desta espécie. Maior percentagem de germinação e maior índice de velocidade de germinação foram observados na ausência da sacarose. Para o crescimento até 30 dias, recomenda-se o uso do meio 1/4MS sem sacarose e, para manutenção das plântulas, in vitro, o meio 1/4MS suplementado com 15 g/L de sacarose. Para a aclimatização de atroveran, o substrato comercial proporcionou maior crescimento das plântulas.

Atroveran (Ocimum selloi Benth. - Lamiaceae) is medicinal plant used for digestive disturbs and inflammation. The objectives of this study were to establish nodal segments, seed germination and in vitro plantlet growth on sucrose and different basal salt concentrations, as well as plantlet acclimatization in different substrates. For establishment and growth, three different basal salt formulations (MS, 1/2MS and 1/4MS) and two concentration of sucrose (15 g/L, 30 g/L and control) were used. For seed germination, MS, 1/2MS, 1/4MS and 0MS (control) and two sucrose (15 g/L, 30 g/L and control) were used. For acclimatization, the substrates sand, Plantmax(r), soil and soil +cattle manure (2:1) were used. The results indicated 15 g/L of sucrose to establish the explant and nodal segment growth. The 1/2MS basal salt formulation was better to establish the explant and 1/4MS to nodal segment growth of O. selloi. The results indicated higher seed germination percentage and germination speed index on medium without sucrose. For growth up to 30 days better results were observed on 1/4MS without sucrose and for plantlet to maintain growth of O. selloi in vitro the better results indicated 1/4MS supplemented with 15 g/L of sucrose. Plantlet acclimatization of O. selloi in the substratum Plantmax(r) gave better growth.

O objetivo do trabalho foi avaliar o potencial dos óleos essenciais extraídos de Hyptis marrubioides, Aloysia gratissima e Cordia verbenacea no controle da ferrugem asiática da soja. A atividade inibitória dos óleos essenciais (aplicados no intervalo de concentração de 0,05 - 2%) sobre a germinação dos urediniósporos de Phakopsora pachyrhizi foram avaliados em teste in vitro. As propriedades curativas e erradicantes dos óleos (aplicados no intervalo de concentração de 0,05 - 0,5%) foram estudadas em casa de vegetação utilizando a cultivar MG/BR 46 (Conquista) suscetível a P. pachyrhizi. Microscopia eletrônica de varredura foi utilizado para investigar o efeito dos óleos essenciais sobre a morfologia dos urediniósporos do fungo. Os tratamentos com os óleos essenciais, em todas as concentrações testadas inibiram totalmente a germinação dos urediniósporos in vitro. A aplicação curativa dos óleos essenciais reduziu a severidade da doença, expressa em área abaixo da curva de progresso em 33 a 41%, enquanto que o fungicida comercial (piraclostrobina + epoxiconazole), empregado como controle positivo reduziu em 61%. Tratamento de plantas infectadas com óleos essenciais produziu alterações morfológicas nas estruturas fúngicas, semelhantes as produzidas pelo fungicida comercial, ou seja, murchamento dos urediniósporos, apressórios, tubos germinativos e paráfise.

The aim of this study was to evaluate the potential of essential oils derived from Hyptis marrubioides, Aloysia gratissima and Cordia verbenacea for controlling Asian soybean rust. The inhibitory activities of the essential oils (applied in a concentration range of 0.05 - 2%) on the germination of Phakopsora pachyrhizi urediniospores were investigated using in vitro assays. The curative and eradicating properties of the oils (applied in a concentration range of 0.05 - 0.5%) were studied under greenhouse conditions using the P. pachyrhizisusceptible soybean cultivar MG/BR 46 (Conquista). Scanning electron microscopy was employed to investigate the effects of the essential oils on the morphology of the P. pachyrhizi urediniospores. The treatment with the essential oils at all concentrations tested led to the total inhibition of spore germination in vitro. The curative application of the essential oils reduced the disease severity, expressed as the area under the disease-progress curves, by 33 to 41%, whereas the commercial fungicide (pyraclostrobin + epoxyconazole) employed as a positive control reduced the severity by 61%. The treatment of infected plants with the essential oils resulted in morphological alterations in the fungal structures that were similar to those produced by the commercial fungicide, namely, a shrivelling of the urediniospores, appressoria, germ tubes and paraphyses.

A fertilização dos solos com adubos orgânicos tem adquirido importância do ponto de vista da concepção de produção vegetal sustentável. Foi objetivo deste trabalho avaliar os efeitos de dosagens de esterco bovino e avícola em Achillea millefolium L. no crescimento vegetativo, teor e composição química do óleo essencial. Na fertilização com o esterco bovino avaliaram-se as doses: 1) Solo sem adubação; 2) solo + 3,0 kg m-2; 3) solo + 6,0 kg m-2; 4) solo + 9,0 kg m-2; 5) solo + 12,0 kg m-2. Na adubação com esterco avícola: 1) solo sem adubação; 2) solo + 1,5 kg m-2; 3) solo + 3,0 kg m-2; 4) solo + 4,5 kg m-2 e 5) solo + 6,0 kg m-2. O delineamento experimental utilizado foi o inteiramente casualizado com quatro repetições por tratamento e quatro plantas por parcela experimental. A colheita ocorreu aos 110 dias e avaliaram-se as biomassas secas da parte aérea e raiz, razão raiz/parte aérea, teor, rendimento e composição química do óleo essencial. Os dados foram submetidos à análise de variância e de regressão. A. millefolium responde com maior intensidade a adubação com esterco avícola que com a bovina, onde a dose de 6 kg m-2 apresentou o maior acúmulo de biomassa seca da parte aérea e maior rendimento de óleo essencial. Independente da adubação das plantas, o óleo essencial da A. millefolium é constituído majoritariamente por camazuleno e os tratamentos aplicados não interferiram expressivamente na composição e teor dos constituintes químicos do óleo.

Fertilization of the soil with organic fertilizers has been gaining importance within the concept of sustainable crop production. This study aimed evaluates the effects of dosages of cattle and poultry manure on Achillea millefolium L. as regards the vegetative growth and the content and chemical composition of its essential oil. For the cattle manure fertilization the dosages evaluated were: 1) soil with no fertilizer; 2) soil + 3.0 kg m-2; 3) soil + 6.0 kg m-2; 4) soil + 9.0 kg m-2 and 5) soil + 12.0 kg m-2. For fertilization with poultry manure: 1) soil without fertilizer; 2) soil + 1.5 kg m-2; 3) soil + 3.0 kg m-2; 4) soil + 4.5 kg m-2 and 5) soil + 6.0 kg m-2. The experimental design was completely randomized, with four replications per treatment and four plants per experimental plot. Harvesting took place at 110 days and the following variables were measured: shoot and root dry biomass; root to shoot ratio and the content, yield and chemical composition of the essential oil. Data were submitted to variance and regression analyses. A. millefolium has more intense response in fertilization with poultry manure than to that of cattle, where the dosage of 6 kg m-2 presented the greatest shoot dry weight and highest yield of essential oil. Without regard to fertilization, the essential oil of A. millefolium consists mainly of chamazulene, with the applied treatments not significantly interfering in the oil chemical composition and content.

The objective of the present work was to induce chromosome doubling in genotypes of Brachiaria ruziziensis with potential for production of good-quality biomass and tolerance/resistance to stress caused by aluminum and spittlebugs. Germinated seeds of B. ruziziensis were immersed in 0.1% colchicine solution for 2 or 3 hours. Ploidy level was determined by flow cytometry and confirmed by chromosome count. Fertility of the tetraploid plants was assessed through evaluation of pollen viability by staining. There was no statistical difference with regard to seedling survival and number of duplicate seedlings between the treatments. Survival rate was 8%, of which 11.45% were tetraploid genotypes. The mean viability of pollen grains from the evaluated tetraploid plants ranged from 51.75 to 55.50%. So, the tetraploids plants obtained from genotypes of a bred population of ruzigrass produce fertile pollen, in percentages that render crosses viable in genetic breeding programs.

O progresso da seca da haste em hibisco foi estudado em quatro épocas e dois métodos de plantio. O delineamento experimental foi em blocos ao acaso, com quatro repetições e os oito tratamentos foram dispostos em esquema fatorial 4 (épocas de plantio) x 2 (métodos de plantio), sendo: semeadura direta em 05/02/03, 06/03/03, 05/04/03 e 15/05/03; transplantio de mudas em 24/12/02, 25/01/03, 24/02/03 e 25/03/03. Imediatamente após o surgimento dos sintomas, avaliou-se a doença a cada 10 dias até o final do ciclo, aos 205 dias, calculando-se a porcentagem de hastes infectadas por planta. Calculou-se a área abaixo da curva de progresso para a incidência (AACPI). As curvas de progresso da doença dos tratamentos foram submetidas ao ajuste dos modelos linear, exponencial, monomolecular, logístico e Gompertz. Houve interação significativa de métodos e épocas de plantio na incidência da doença. Constatou-se menor incidência da seca da haste em transplantio de mudas comparado à semeadura direta em todas as épocas de plantio. Verificou-se aumento da incidência proporcionado pelo atraso na época de plantio nos dois métodos. O modelo exponencial foi o que melhor descreveu o comportamento da doença em todos os tratamentos. As diferenças estatísticas entre os tratamentos, considerando a taxa de progresso, não refletiram a intensidade da doença no campo. Na mesma época de plantio, as quantidades inicial e máxima da doença, observadas na semeadura direta, foram superiores aos tratamentos referentes ao transplantio de mudas, coerentes com os valores da AACPI. Registrou-se uma relação direta entre queda de temperatura e aumento da incidência da seca da haste.

Stem blight progress in roselle was studied in four periods and two planting methods. Experimental design was in randomized blocks with four replicates and eight treatments in 4 (periods) x 2 (planting methods) factorial arrangement: direct sowing on 05/02/03, 06/03/03, 05/04/03, 15/05/03 and seedling transplanting on 24/12/02, 25/01/03, 24/02/03, 25/03/03. Immediately after the emergence of symptoms, the disease was evaluated at every 10 days until the end of the cycle, at 205 days, and the percentage of infected stems was calculated. The area under the progress curve of the incidence (AUPCI) was calculated. The disease progress curves for the treatments were adjusted to linear, exponential, monomolecular, logistic and gompertz models. There was significant interaction of methods and planting periods for the disease incidence. Lower incidence of stem blight was noted for seedling transplanting compared to direct sowing in all planting periods. There was increased incidence due to the delay in planting for the two methods. The exponential model best described the disease behavior in all treatments. The statistical differences among treatments considering the progress rate did not reflect the disease intensity in the field. In the same planting period, the initial and maximum quantities of the disease, at the direct sowing, were superior to the treatments related to the seedling transplanting, consistent with the AUPCI values. A direct relationship was recorded between temperature fall and increased incidence of stem blight.

Mentha x piperita L. é uma planta aromática e medicinal pertencente à família Lamiaceae, popularmente conhecida como hortelã-pimenta. No trabalho, objetivou-se verificar o efeito das fontes de adubação orgânica na produção de biomassa, no rendimento e na composição química do óleo essencial de hortelã-pimenta (Mentha piperita L.). O experimento foi conduzido em DIC, em esquema fatorial 2 x 5, com duas fontes de esterco, bovino e avícola, e cinco doses (0, 3, 6, 9 e 12 kg m-2), com quatro repetições cada. As diferentes doses de estercos bovino e avícola influenciaram significativamente de forma benéfica a produção de biomassa das plantas e também outras variáveis de crescimento como área foliar, razão de peso foliar, razão de área foliar, relação raiz:parte aérea, rendimento e composição química do óleo de hortelã-pimenta. Utilizar adubação orgânica para a obtenção máxima de biomassa seca total as doses de 9,0 kg m-2 de esterco bovino e 8,3 kg m-2 de esterco avícola. O maior rendimento de óleo é obtido com a aplicação de 11,8 kg m-2 de esterco avícola. Diferenças na composição química do óleo essencial foram observadas para três componentes (mentona, pulegona e acetato de mentila) sem mudança significativa no conteúdo de mentol.

Mentha x piperita L. is an aromatic and medicinal species belonging to the family Lamiaceae that is popularly known as peppermint. The aim of this study was to evaluate the effects of organic fertilizer sources on the biomass production, yield and chemical composition of peppermint (Mentha piperita L.) essential oil. The experiment was conducted using a completely randomized design (CRD) with a 2 x 5 factorial scheme, two sources of manure (cattle and poultry), five doses (0, 3, 6, 9 and 12 kg m-2) and four replicates. Different doses of cattle and poultry manure significantly affected plant biomass production and the responses of other variables, including leaf area, leaf weight ratio, leaf area ratio, root:shoot ratio, yield and chemical composition. Organic fertilizer doses of 9.0 kg m-2 cattle manure and 8.3 kg m-2 poultry manure to obtain the maximum total dry biomass. The highest yield of essential oil was obtained by applying 11.8 kg m-2 poultry manure. Differences in the chemical composition of the essential oil were observed for only three components (menthone, pulegone and menthyl acetate) without significant changes in the menthol content.

The aim of the study was to evaluate the antifungal activity of essential oils from "hortelã do campo" (Hyptis marrubioides), "alfazema-do-Brasil" (Aloysia gratissima) and "erva-baleeira" (Cordia verbenacea) and their efficacy in the treatment of soybean seeds infected with Colletotrichum truncatum. In vitro assays were performed to evaluate the effects of the oils on spore germination, mycelial growth, and the production and viability of C. truncatum conidia. Soybean seeds inoculated with C. truncatum were treated with essential oils at concentrations ranging from 0.5 to 2% and grown under greenhouse conditions. Seed health and germination percentages were evaluated according to standard protocols. Seedling emergence, stand establishment and the percentages of dead seedlings were determined, together with the emergence speed index, plantlet height and dry weight of aerial biomass. The oils from H. marrubioides, C. verbenacea and A. gratissima inhibited the germination and production of conidia as well as the growth of C. truncatum. At concentrations ≥ 1%, the effectiveness of the oils against soybean anthracnose was superior to, or at least comparable with, that of the fungicide carbendazim. The viability of conidia and the germination of soybean seeds were not affected by any of the treatments with essential oils. It is concluded that essential oils from H. marrubioides, A. gratissima and C. verbenacea have potential as alternatives to synthetic fungicides in the control of anthracnose in soybean seeds.