The isolation and characterization of endophytic microorganisms from Hyptis marrubioides Epling roots

Endophytic microorganisms asymptomatically colonize healthy plant tissues and may be related to the plant's resistance to attack by pathogens or even to the synthesis of secondary metabolites. The present study was aimed at isolating and characterizing endophytic strains from the root system of Hyptis marrubioides. Coarse and fine root fragments were collected for diaphanization and surface disinfection to isolate endophytes. After 10 days of incubation, we obtained the colonization rate (CR) of the fragments and the endophytic were purified and maintained in culture medium. The bacteria were partially characterized using Gram stain and a catalase test. Fungi were identified by distinguishing between reproductive structures using a microculture technique. While observing diaphanized root fragments, we found arbuscular mycorrhizal fungi (AMF) and dark septate endophytic (DSE) fungi in the fine and coarse roots of H. marrubioides. The endophytic CR was more significant in coarse root fragments. In both types of roots, the percentage of bacteria was higher than the percentage of fungi. Gram positive and catalase-positive bacteria accounted for the majority of bacterial isolates, which were predominantly bacilli. Of all the fungal isolates, the majority had sporulating mycelium, which mainly consisted of fungi from the genus Penicillium, Fusarium, Trichoderma and Papulaspora.Keywords: Bacteria, fungus, Lamiaceae, root syste

Establishment of Eucalyptus grandis W. Hill ex Maiden in vitro using commercial products for seed treatment

Given the current demand for timber from forest species, there is a need to develop new strategies for the mass propagation of eucalyptus. Therefore, this study aimed to determine the effect of different doses of Standak Top® and CoMo Raiz® on the establishment of Eucalyptus grandis W. Hill ex Maiden from seeds in vitro. The experimental design was completely randomized in a 4 × 3 + 1 factorial arrangement (four concentrations: 1, 2, 3, and 4 mL L-1 of the commercial products Standak Top®, CoMo Raiz®, a mixture of both, and a control treatment) with 20 replicates. The following characteristics were evaluated: Contamination level, shoot length, and the number of leaves. No contamination was observed for the different doses of Standak Top®. Additions of 1 to 3 mL L-1 of Standak Top® to the culture media yielded the greatest shoot length, and the additions of 2 to 3 mL L-1 yielded the greatest number of leaves. Mixing Standak Top® and CoMo Raiz® did not significantly enhance the measured characteristics.Keywords: Standak Top®, CoMo Raiz®, tissue culture, asepsis, culture mediaAfrican Journal of Biotechnology Vol. 12(25), pp. 3963-396

MUDAS DE ESPÉCIES ARBÓREAS INOCULADAS COM BACTÉRIAS SOLUBILIZADORAS DE FOSFATO E FUNGOS MICORRÍZICOS ARBUSCULARES

This study aimed to verify the inoculation of P-solubilizing bacteria effect on the growth of tree species seedlings cultivated under nursery conditions. Acacia holosericea, Mimosa caesalpiniifolia, Anadenanthera macrocarpa, Enterolobium contortisiliquum, Schinus terebinthifolius and Eucalyptus grandis were grown in nursery during 11 months. N2-fixing tree species were inoculated with rhizobia and arbuscular mycorrhizal fungi (AMF) while Non-N2-fixing tree species were inoculated only with AMF. Otherwise, half of the plants were inoculated with P-solubilizing bacteria. Population of P-solubilizing bacteria inoculated decreased during plant growth. On the other hand, these bacteria stimulated the growth of Anadenanthera macrocarpa, Mimosa caesalpiniifolia and Acacia holosericea in spite of inhibiting growth of Enterolobium contortisiliquum.Este trabalho objetivou verificar o efeito da inoculação de bactérias solubilizadoras de fosfato na formação de mudas de espécies arbóreas em viveiro. Mudas de Acacia holosericea, Mimosa caesalpiniifolia, Anadenanthera macrocarpa, Enterolobium contortisiliquum, Schinus terebinthifolius e Eucalyptus grandis foram formadas em viveiro durante 11 meses. As espécies fixadoras de N2 foram inoculadas com rizóbio e fungos micorrízicos arbusculares (FMAs) enquanto que as não fixadoras apenas com FMAs. Além disso, metade das mudas foi inoculada com bactérias solubilizadoras de fosfato. A população inoculada de bactérias solubilizadoras decresceu durante a formação de mudas. Por outro lado, a inoculação dessas bactérias foi benéfica para formação de mudas de Anadenanthera macrocarpa, Mimosa caesalpiniifolia e Acacia holosericea. inibindo, entretanto, o desenvolvimento de Enterolobium contortisiliquum

Phosphate solubilization and synergism between P-solubilizing and arbuscular mycorrhizal fungi

O objetivo deste trabalho foi avaliar a capacidade de solubilização de fosfato de alumínio e apatita de Araxá por diversos isolados de fungos solubilizadores de fosfato e o sinergismo entre o fungo solubilizador de fosfato, FSF 7, e fungos micorrízicos arbusculares, na promoção do crescimento de trevo fertilizado com fosfato de alumínio. Dois experimentos foram conduzidos, o primeiro em laboratório e o segundo em câmaras de cultivo. No primeiro experimento, os isolados FSF 7, FSF 9, FSF 21 e FSF 22, mais controle foram incubados em meio líquido, sob agitação, a 28ºC, por oito dias. Avaliou-se o pH e P solúvel no segundo, quarto e oitavo dia de incubação. No segundo experimento, semeou-se trevo em copos de plástico contendo 300 g de substrato esterilizado, fertilizado com fosfato de alumínio, 3 g L-1, com e sem FSF 7 e fungos micorrízicos. O delineamento foi inteiramente casualizado, esquema fatorial 2x2 (presença e ausência de FSF 7 e fungos micorrízicos), com cinco repetições. No primeiro experimento, foram encontradas maiores quantidades de P solúvel no meio contendo fosfato de alumínio. O FSF 7 aumentou a solubilização desse fosfato. O crescimento do trevo foi favorecido pela presença do FSF 7 e fungos micorrízicos arbusculares, o que evidencia sinergismo entre esses microrganismos.The objective of this work was to evaluate the ability of several P-solubilizing fungi to solubilize aluminum phosphate and Araxá apatite as well as the synergism between the P-solubilizing fungus, PSF 7, and arbuscular mycorrhizal fungi to promote clover growth amended with aluminum phosphate. Two experiments were carried out, the first under laboratory conditions and the second in a controlled environmental chamber. In the first experiment, PSF 7, PSF 9, PSF 21 and PSF 22 isolates plus control were incubated in liquid medium at 28ºC for eight days. On the 2nd, 4th and 8th day of incubation, pH and soluble P were determined. In the second experiment, clover was sowed in plastic pots containing 300 g of sterilized substrate amended with aluminum phosphate, 3 g L-1, in presence and absence of PSF 7 isolate and arbuscular mycorrhizal fungi. A completely randomized design, in factorial outline 2x2 (presence and absence of PSF 7 and arbuscular mycorrhizal fungi) and five replicates were used. In the first experiment, higher P content was detected in the medium containing aluminum phosphate. PSF 7 is the best fungi isolate which increases aluminum solubilization with major tolerance to Al3+. Clover growth was stimulated by presence of PSF 7 and arbuscular mycorrhizal fungi. There is synergism between microorganisms utilized to improve plant nutrition

Phosphate solubilization in solid and liquid media by soil bacteria and fungi

O objetivo deste trabalho foi avaliar a capacidade e a eficiência de solubilização de CaHPO4, AlPO4 e apatita de Araxá em meio sólido, e de AlPO4 e apatita de Araxá em meio líquido, por fungos (Aspergillus) e bactérias (Enterobacteriaceae) do solo. Em meio sólido, todos solubilizaram CaHPO4, nenhum solubilizou apatita de Araxá e apenas o isolado de fungo FSF 7 solubilizou AlPO4. Em meio líquido, todos solubilizaram AlPO4 e apatita de Araxá. A seleção de solubilizadores deve ser feita com a quantificação do potencial de solubilização em meio líquido.The objective of this work was to evaluate the ability and efficiency of solubilization of CaHPO4, AlPO4 and Araxá apatite in solid medium, and AlPO4 and Araxá apatite in liquid medium. Soil P-solubilizing fungi (Aspergillus) and P-solubilizing bacteria (Enterobacteriaceae) were tested. In solid medium, all isolates solubilized CaHPO4, not any isolate solubilized Araxá apatite, and one fungus isolate (PSF 7) solubilized AlPO4. In liquid medium, all isolates solubilized AlPO4 and Araxá apatite. Screening of P-solubilizing microorganisms must be done by quantifying their potential of phosphate solubilization in liquid growth medium

Phosphate solubilization in solid and liquid media by soil bacteria and fungi

O objetivo deste trabalho foi avaliar a capacidade e a eficiência de solubilização de CaHPO4, AlPO4 e apatita de Araxá em meio sólido, e de AlPO4 e apatita de Araxá em meio líquido, por fungos (Aspergillus) e bactérias (Enterobacteriaceae) do solo. Em meio sólido, todos solubilizaram CaHPO4, nenhum solubilizou apatita de Araxá e apenas o isolado de fungo FSF 7 solubilizou AlPO4. Em meio líquido, todos solubilizaram AlPO4 e apatita de Araxá. A seleção de solubilizadores deve ser feita com a quantificação do potencial de solubilização em meio líquido.The objective of this work was to evaluate the ability and efficiency of solubilization of CaHPO4, AlPO4 and Araxá apatite in solid medium, and AlPO4 and Araxá apatite in liquid medium. Soil P-solubilizing fungi (Aspergillus) and P-solubilizing bacteria (Enterobacteriaceae) were tested. In solid medium, all isolates solubilized CaHPO4, not any isolate solubilized Araxá apatite, and one fungus isolate (PSF 7) solubilized AlPO4. In liquid medium, all isolates solubilized AlPO4 and Araxá apatite. Screening of P-solubilizing microorganisms must be done by quantifying their potential of phosphate solubilization in liquid growth medium

Chemical composition of the essential oil of Psidium guajava leaves and its toxicity against Sclerotinia sclerotiorum

Globally, the fungus Sclerotinia sclerotiorum is considered as one of the most important phytopathogens, since it affects the production of several economically important crops. Further, it is difficult to control, thus increasing the use of pesticides. Therefore, the search for new substances, especially those extracted from plants, has received special attention to control this plant pathogen. The objective of the present study was to evaluate the yield and chemical composition of the essential oil extracted from the fresh leaves of guava collected during the rainy and dry seasons, and also to evaluate its toxicity against S. sclerotiorum. The experiment was a completely randomized design with five treatments and six replicates. The essential oil was extracted by hydrodistillation of the leaves and analyzed by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. The main compounds identified in the essential oil were trans-caryophyllene and ?-humulene. The essential oil at a concentration of 300 ?L exhibited 90% inhibition of the mycelial growth of S. sclerotiorum. This confirmed the antifungal potential of the essential oil of the guava leaves during both the sampling seasons

Micro-organismos solubilizadores de fosfatos em fertilizantes organominerais para incremento da produtividade de Vigna unguiculata (L.) Walp.

This work aimed to evaluate the interaction between P-solubilizing microorganisms and organomineral fertilizers in order to increase the cowpea nutrition and yield under field conditions. One field trial was carried out in a randomized complete block design arranged in subdivided plots (7 x 3) with four replicates. The organominerals (poultry litter, swine manure, filter cake and soot from chimneys) as well as triple superphosphate (TSP) with and without sulfur and the control treatment (no fertilizer addition), were considered the primary factor. The secondary factor was constituted by inoculation of Bradyrhizobium sp. SEMIA 6462 (Simbiose Nod Caupi®), one P-solubilizing bacteria (MBSF2) as well as no inoculation treatment. The MBSF2 inoculation combined to the soot organomineral increased the shoot length at 50 DAE. The stem diameter, shoot and root dry matter at 50 DAE were increased by Bradyrhizobium spp. inoculation and poultry litter. Also, the stem diameter was increased using filter cake organomineral and both inoculants. The nodules number was also increased by use of that organomineral combined to Bradyrhizobium spp.Con este trabajo se evaluó la interacción de microorganismos solubilizadores de fosfato asociados a composiciones de fertilizantes organominerales, con el objetivo de incrementar la nutrición y productividad del caupí en campo. El ensayo se realizó en un diseño experimental de bloques al azar, con parcelas subdivididas en esquema 7 x 3, con cuatro repeticiones, y en el factor primario se consideraron los tratamientos de fertilización: cama avícola, estiércol porcino, cachaza y hollín (organominerales ), superfosfato triple con azufre y superfosfato triple sin azufre (fertilizantes químicos industrializados), además del tratamiento de control (ausencia de fertilizante). Como segundo factor se consideraron los tratamientos de inoculación: Bradyrhizobium spp. SEMIA 6462 (Symbiosis Nod Caupi®), inoculación del aislado bacteriano solubilizador de fosfatos MBSF2, perteneciente a la Colección de Microorganismos del Laboratorio de Microbiología Agrícola de la IF Goiano y ausencia de inoculación. El solubilizante MBSF2 en el organomineral a base de hollín mostró mejores respuestas en relación al largo de brotes a los 50 DDE. Las variables diámetro del tallo, masa seca de la parte aérea y de la raíz del caupí se ven favorecidas con la inoculación de Bradyrhizobium spp. y cultivo con organomineral a base de yacija avícola a los 50 DDE. El diámetro de tallo se vio favorecido por la adición de organomineral a la base de cachaza combinado con ambos inoculantes, así como también se incrementó el número de nódulos con este organomineral, combinado con la inoculación de Bradyrhizobium spp.Com este trabalho, avaliou-se a interação dos micro-organismos solubilizadores de fosfato associados a composições de fertilizantes organominerais, visando incrementar a nutrição e a produtividade de feijão-caupi em campo. O ensaio foi conduzido em delineamento experimental de blocos casualizados, com parcelas subdivididas no esquema 7 x 3, com quatro repetições, sendo que no fator primário, foram considerados os tratamentos de adubação: cama de aviário, dejetos suínos, torta de filtro e fuligem (organominerais), superfosfato triplo com enxofre e superfosfato triplo sem enxofre (fertilizantes químicos industrializados), além do tratamento controle (ausência de fertilizante). Como segundo fator, foram considerados os tratamentos de inoculação: Bradyrhizobium spp. SEMIA 6462 (Simbiose Nod Caupi®), inoculação do isolado bacteriano solubilizador de fosfatos MBSF2, pertencente à Coleção de Micro- organismos do Laboratório de Microbiologia Agrícola do IF Goiano e ausência de inoculação. O solubilizador MBSF2 no organomineral com base de fuligem demonstrou melhores respostas em relação ao comprimento de parte aérea aos 50 DAE. As variáveis diâmetro de caule, massa seca da parte aérea e da raiz de feijão-caupi são favorecidas com a inoculação de Bradyrhizobium spp. e cultivo com organomineral a base de cama de aviário aos 50 DAE. O diâmetro de caule foi favorecido pela adição de organomineral à base de torta de filtro combinado com ambos os inoculantes, assim como o número de nódulos incrementado com este organomineral, aliado à inoculação com Bradyrhizobium spp

Efecto de la inoculación de microorganismos solubilizadores de fosfato y hongos micorrícicos arbusculares en plantas de Eugenia dysenterica crecidas en diferentes sustratos

Phosphate solubilizing microorganisms (PSM) and arbuscular mycorrhizal fungi (AMF) represent alternative strategies to reduce the cost and increase the production of cagaita (Eugenia dysenterica) seedlings associated with different substrates. This study aimed to assess the effect of inoculating PSM and AMF in different substrates for cagaita (Eugenia dysenterica) culturing. The experiment was installed with a completely randomized design, using a 4 × 2 factorial scheme, with four inoculation treatments (PSM, AMF, PSM + AMF, and Control – absence of inoculation), and two soils substrates (pure sandy substrate and mixed substrate). The substrates and microorganism had influence in cagaita seedling growth. The pure substrate conferred better performance of plant growth parameters. In this substrate, cagaita seedlings had higher stem diameter, shoot fresh and dry weight, root volume and root dry weight. The cultivation of seedlings in pure substrate inoculated with AMF and PSM provided greater Mo content in the leaves. The higher root volume of cagaita seedlings was obtained with the inoculation of PSM. A sandy substrate seems to be the most adequate for the cultivation of cagaita seedlings. In addition, co-inoculation provides higher Fe, Mg, and K content in the leaves, as this work showed.Los microorganismos solubilizadores de fosfato (PSM) y los hongos micorrízicos arbusculares (HMA) representan estrategias alternativas para reducir el costo y aumentar la producción de plántulas de cagaita (Eugenia dysenterica) asociadas a diferentes sustratos. Este estudio tuvo como objetivo evaluar el efecto de la inoculación de PSM y HMA en diferentes sustratos para el cultivo de cagaita (Eugenia dysenterica). El experimento se instaló con un diseño completamente al azar, utilizando un esquema factorial 4 × 2, con cuatro tratamientos de inoculación (PSM, HMA, PSM + HMA y Control - ausencia de inoculación), y dos sustratos de suelo (sustrato arenoso puro y sustrato mixto). Los sustratos y microorganismos influyeron en el crecimiento de las plántulas de cagaita. El sustrato puro propició un mejor desempeño de los parámetros de crecimiento de las plantas. En este sustrato, las plántulas de cagaita presentaron mayor diámetro de tallo, masa fresca y seca de brotes, volumen de raíz y masa seca de la raíz. El cultivo de plántulas en sustrato puro inoculadas con HMA y PSM proporcionó mayor contenido de Mo en las hojas. El mayor volumen de raíces de plántulas de cagaita se obtuvo con la inoculación de PSM. Un sustrato arenoso parece ser el más adecuado para el cultivo de plántulas de cagaita. Además, la coinoculación proporciona un mayor contenido de Fe, Mg y K en las hojas, como mostró este trabajo

Produtividade da soja em associação ao fungo micorrízico arbuscular Rhizophagus clarus cultivada em condições de campo

Soybeans are key to agribusiness progress, but their production can be affected by climate change. Thus, alternatives that increase the yield of the plants under adverse conditions are fundamental, and the arbuscular mycorrhizal fungi (FMA) stand out. Therefore, they associate the roots of the plants, increasing the absorption of water and nutrients. Thus, the objective of this work was to evaluate soybean yield in the field experiment in association with FMA Rhizophagus clarus under conditions of irrigated and non-irrigated system. In the end, agronomic and symbiosis parameters were evaluated with FMA. The experimental design was in randomized blocks with subdivided plots, the means obtained were submitted to analysis of variance and compared by the Tukey test (5%), using SISVAR software. Soybean plants when associated with FMA and cultivated in non-irrigated conditions, obtained higher productivity than plants in the irrigated system and weight of 1000 grains. In this way, it is concluded that inoculation benefits soybean yield under non-irrigated system conditions.A soja é fundamental para o progresso do agronegócio, porém sua produtividade pode ser afetada pelas mudanças climáticas. Assim, alternativas que aumentem o rendimento das plantas em condições adversas são fundamentais, e os fungos micorrízicos arbusculares (FMA) destacam-se, pois, associam-se as raízes das plantas aumentando a absorção de água e nutrientes. Assim, o objetivo deste trabalho foi avaliar a produtividade de plantas de soja a campo experimental em associação com o FMA Rhizophagus clarus sob condição de sistema irrigado e não irrigado. Ao final, avaliou-se parâmetros agronômicos e de simbiose com o FMA. O delineamento experimental foi em blocos casualizados com parcelas subdivididas, as médias obtidas foram submetidas à análise de variância e comparadas pelo teste Tukey (5%), utilizando software SISVAR. Plantas de soja quando associadas com FMA e cultivadas em condição não irrigada, obtiveram maior produtividade do que plantas no sistema irrigado, além de peso de 1000 grãos. Desta forma, conclui-se que a inoculação beneficia a produtividade da soja em condições de sistema não irrigado