RESUMO
Meloidogyne javanica is among the most important nematodes that damage soybean, and although genetic resistance is the ideal control measure, there are few cultivars described as resistant among those recommended for southern Brazil. The objective of this work was to evaluate the reaction of soybean cultivars to M. javanica. The inoculum of nematodes (Est. J3) was obtained from soybean plants and inoculated into tomato plants cultivar "Santa Cruz". Thirty-seven soybean cultivars widely used in the South, Southeast and Midwest of Brazil were used in the experiment. For each plant a suspension of 5,000 eggs + juveniles of second stage of M. javanica was inoculated into a sterile soil hole in 2-liter pots with six replications. The evaluation of root weight, number of galls, number of nematodes was 60 days after M. javanica inoculation. The results were subjected to analysis of variance, and the averages of each treatment were compared to each other by the Scott-Knott cluster test at 5% probability. Even though M. javanica presented RF> 1.00 in all soybean genotypes tested, different levels of susceptibility were observed. Thus, the lowest reproduction of the root-knot nematode was observed in M ââ5947 IPRO, HO AMAMBAY IPRO, BMX GARRA IPRO and FPS ATALANTA.
Assuntos
Fabaceae , Tylenchoidea , Animais , Genótipo , Raízes de Plantas/genética , Reprodução/genética , Glycine max/genética , Tylenchoidea/genéticaRESUMO
Phytoremediation is an alternative for remediating soil contamination by copper, and its efficiency has been shown to increase when arbuscular mycorrhizal fungi (AMF) and earthworms are separately inoculated into the soil. This study evaluated the isolated and combined effects of inoculating earthworms and arbuscular mycorrhizal fungi into a sandy soil on copper phytoremediation by Canavalia ensiformis. The plants were grown in a greenhouse in soil contaminated with 100â¯mg Cu kg-1 with and without being inoculated with the arbuscular mycorrhizal fungus Rhizoglomus clarum and the earthworm Eisenia andrei. The availabilities of solid-phase Cu and other nutrients in the soil solution and plant growth were evaluated along with Cu phytotoxicity based on photochemical efficiency and oxidative stress enzyme activity. Accumulation of Cu and other nutrients in the shoots and roots; mycorrhizal colonization, nodulation, and reproduction; and Cu accumulation in the earthworm tissues were also evaluated. The copper caused photosynthetic and biochemical damage that reduced the shoot dry weight by 44% and the root dry weight by 29%. However, the arbuscular mycorrhizal fungus alleviated the Cu toxicity to the plant and increased the shoot dry weight by 81% in the contaminated soil. The earthworms increased the Cu uptake and translocation to the shoot by 31%. The combined presence of the arbuscular mycorrhizal fungus and earthworms in the contaminated soil increased the growth and Cu content of the aerial plant tissues, yielding a 200% increase in Cu accumulation (metal contentâ¯×â¯biomass) in the C. ensiformis shoots. Combined inoculation with earthworms and arbuscular mycorrhizal fungi increased copper phytoextraction by Canavalia ensiformis in a sandy soil.
Assuntos
Canavalia/metabolismo , Cobre/análise , Glomeromycota/metabolismo , Micorrizas/metabolismo , Oligoquetos/metabolismo , Poluentes do Solo/análise , Animais , Biodegradação Ambiental , Biomassa , Canavalia/crescimento & desenvolvimento , Glomeromycota/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Solo/químicaRESUMO
The current study aimed to test the hypothesis that both land-use change and soil type are responsible for the major changes in the fungal and archaeal community structure and functioning of the soil microbial community in Brazilian Pampa biome. Soil samples were collected at sites with different land-uses (native grassland, native forest, Eucalyptus and Acacia plantation, soybean and watermelon field) and in a typical toposequence in Pampa biome formed by Paleudult, Albaqualf and alluvial soils. The structure of soil microbial community (archaeal and fungal) was evaluated by ribosomal intergenic spacer analysis and soil functional capabilities were measured by microbial biomass carbon and metabolic quotient. We detected different patterns in microbial community driven by land-use change and soil type, showing that both factors are significant drivers of fungal and archaeal community structure and biomass and microbial activity. Fungal community structure was more affected by land-use and archaeal community was more affected by soil type. Irrespective of the land-use or soil type, a large percentage of operational taxonomic unit were shared among the soils. We accepted the hypothesis that both land-use change and soil type are drivers of archaeal and fungal community structure and soil functional capabilities. Moreover, we also suggest the existence of a soil microbial core.
Assuntos
Archaea/isolamento & purificação , Fungos/isolamento & purificação , Microbiologia do Solo , Solo/química , Árvores/microbiologia , Archaea/classificação , Archaea/genética , Biodiversidade , Brasil , Ecossistema , Fungos/classificação , Fungos/genéticaRESUMO
Research and commercial production of bioherbicides occur to a lesser extent compared to bioinsecticides and biofungicides. In order to contribute to developing new bioherbicides with low environmental impact, this study aimed to increase the phytotoxicity of metabolites of the fungus Mycoleptodiscus indicus UFSM 54 by optimizing solid and submerged fermentation and evaluate the ecotoxicological effects on earthworms (Eisenia andrei). The Plackett-Burman and central composite rotatable designs were used to optimize metabolite phytotoxicity. The variables optimized in the fermentation were temperature, agitation, pH, water volume in the culture medium, glucose concentration, and yeast extract. The fungus was grown on sugarcane bagasse substrate, and its metabolites were applied to detached Cucumis sativus, Conyza sp., and Sorghum bicolor leaves and used in an avoidance test and acute exposure to earthworms. Metabolite phytotoxicity in submerged fermentation was optimized at 35 °C, 50 rpm, and 1.5 g l-1 of glucose and in solid fermentation at 30-37 °C and in 14-32 ml of water. The metabolites severely damaged germination, initial growth, and leaves of the three plants, and at the doses tested (maximum of 113.92 ml kg-1), the metabolites of M. indicus UFSM 54 were not toxic to earthworms.
Assuntos
Celulose , Saccharum , Celulose/metabolismo , Meios de Cultura/metabolismo , Fermentação , Glucose , Saccharum/metabolismo , ÁguaRESUMO
An alternative to controlling weeds resistant to conventional herbicides is the isolation of new active principles. Fungi can produce phytotoxic metabolites that may be used in the development of new herbicides. The objectives of this study were: (1) isolate, select, and identify a fungus producer of phytotoxic metabolites and (2) optimize the culture conditions of this fungus in a low-cost culture medium, with the aim of increasing the phytotoxic effects of their metabolites in weeds and commercial plants. Fungi were isolated from the leaves of Conyza sp. with disease symptoms and selected according to the production of phytotoxic metabolites in solid and submerged fermentation in a low-cost culture medium. A Plackett-Burman Design and Central Composite Rotational Design were used to optimize the conditions of temperature, agitation, pH, and concentrations of glucose and yeast extract in submerged fermentation. The phytotoxic metabolites produced under optimal conditions were tested on 10 commercial plants and weeds that are difficult to control. Of the nine fungi isolated, Mycoleptodiscus indicus UFSM54 produced higher leaf lesions. The production of phytotoxic metabolites was optimized when the fungus was cultivated at 35°C, 50â rpm, and 1.5â gâ L-1 of glucose in submerged fermentation. The metabolites of M. indicus caused severe phytotoxic effects on germination and seedling growth, and enhanced lesion development on detached plant leaves. The present study is the first to report on the production of phytotoxic metabolites by M. indicus, a potential producer of bioherbicides.
Assuntos
Ascomicetos , Herbicidas , Ascomicetos/metabolismo , Meios de Cultura/metabolismo , Meios de Cultura/farmacologia , Fermentação , Glucose , Herbicidas/toxicidade , Plantas Daninhas/metabolismoRESUMO
Due to high global demand, large amounts of abbattoir waste are generated from pork production. Mismanagement of abattoir waste on agricultural lands can result in soil and water contamination with pathogens and contaminants like metals and nutrients. Therefore, possible effects on soil organisms prior to application should be evaluated. Thus, the aim of this study was to determine the effects of fresh pig abattoir waste (PAWf) and waste after stabilization processes on E. andrei through tests of avoidance behavior, acute toxicity and chronic toxicity. In order to do this, the waste was evaluated fresh (i.e., non-treated), and after aerated composting (PAWa), natural composting (PAWn) and vermicomposting (PAWv). In addition, we used a natural soil with no history of agricultural use as control soil. The evaluation was based on avoidance behavior, mortality, initial and final earthworm weight, and reproduction, in addition to a set of enzyme assays formed by acetylcholinesterase, lipid peroxidation, catalase and glutathione S-transferase measured over time. The ecotoxicological results showed that PAWf and PAWa increased AChE activity at different experimental periods, while PAWn decreased activity at 14 days compared to the control. PAWf and PAWa increased TBARS levels at 7 and 14 days, respectively. CAT activity decreased at 3, 7 and 14 days in PAWv, while GST activity increased at 3 days in PAWa and at 3 and 14 days in PAWf compared to the control. In the acute toxicity test, PAWa and PAWn had a toxic effect on E. andrei, resulting in 100% mortality at 14 days of exposure. Based on our findings, pig abattoir waste should undergo vermicomposting prior to agricultural application to soils.
Assuntos
Resíduos Industriais , Oligoquetos , Poluentes do Solo , Matadouros , Animais , Ensaios Enzimáticos , Resíduos Industriais/análise , Oligoquetos/efeitos dos fármacos , Solo/química , Poluentes do Solo/toxicidade , SuínosRESUMO
The chitinases have extensive biotechnological potential but have been little exploited commercially due to the low number of good chitinolytic microorganisms. The purpose of this study was to identify a chitinolytic fungal and optimize its production using solid state fermentation (SSF) and agroindustry substrate, to evaluate different chitin sources for chitinase production, to evaluate different solvents for the extraction of enzymes produced during fermentation process, and to determine the nematicide effect of enzymatic extract and biological control of Meloidogyne javanica and Meloidogyne incognita nematodes. The fungus was previously isolated from bedbugs of Tibraca limbativentris Stal (Hemiptera: Pentatomidae) and selected among 51 isolated fungal as the largest producer of chitinolytic enzymes in SSF. The isolate UFSMQ40 has been identified as Trichoderma koningiopsis by the amplification of tef1 gene fragments. The greatest chitinase production (10.76 U gds-1) occurred with wheat bran substrate at 55% moisture, 15% colloidal chitin, 100% of corn steep liquor, and two discs of inoculum at 30 °C for 72 h. Considering the enzymatic inducers, the best chitinase production by the isolated fungus was achieved using chitin in colloidal, powder, and flakes. The usage of 1:15 g/mL of sodium citrate-phosphate buffer was the best ratio for chitinase extraction of SSF. The Trichoderma koningiopsis UFSMQ40 showed high mortality of M. javanica and M. incognita when applied to treatments with enzymatic filtrated and the suspension of conidia.
Assuntos
Quitina/metabolismo , Quitinases/biossíntese , Fermentação , Hypocreales/enzimologia , Animais , Percevejos-de-Cama/microbiologia , Agentes de Controle Biológico , Biotecnologia , Fibras na Dieta , Nematoides/efeitos dos fármacos , Esporos Fúngicos/metabolismo , Temperatura , Zea maysRESUMO
The knowledge regarding earthworm species richness in subtropical Brazil is limited, particularly in the state of Rio Grande do Sul (RS), where only a few sites have been sampled. In this study we assessed earthworm richness in different ecosystems of RS, prioritizing un-sampled regions. Fifteen ecosystems, including native vegetation and other ecosystems with variable levels of disturbance were sampled in 30 counties in RS, totaling 77 sampling points, mainly in the Pampa biome. Qualitative sampling was performed by handsorting soil monoliths and fixing the earthworms in 4% formalin solution. Species identification was based on morphological characters, and species richness and Shannon (H) and McIntosh (U) diversity indices were calculated for each ecosystem. Twenty-one earthworm species were identified, belonging to seven families: Glossoscolecidae (8), Rhinodrilidae (2), Ocnerodrilidae (4), Megascolecidae (4), Acanthodrilidae (1), Lumbricidae (1) and Criodrilidae (1). From these, ten are new species belonging to the genera: Glossoscolex (6), Fimoscolex (1), Kerriona (1), Eukerria (1), and one aquatic species of the Criodrilidae family, belonging to a new genus. Most of the native species (Urobenus brasiliensis, Fimoscolex n.sp.1 and the Glossoscolex spp.) predominated in ecosystems little altered by human activity, while exotic (Amynthas gracilis, Amynthas rodericensis, Metaphire californica, Aporrectodea trapezoides) and peregrine species (Pontoscolex corethrurus) predominated in areas with more human disturbance. Native ecosystems with lower disturbance, particularly forests and native pastures had higher diversity than disturbed sites. This is the first record of A. rodericencis for Brazil and most sites represent new collection records for the known species in RS.
Assuntos
Oligoquetos , Animais , Brasil , Ecossistema , Florestas , SoloRESUMO
Tuber floridanum is the first truffle species reported in Brazil and little is known about its nutritional properties and ecology. Therefore, this study aimed to (1) determine T. floridanum aroma and nutritional properties and (2) analyze cultivation and fruiting conditions, including potential crop pests and market value. Fruiting bodies of T. floridanum showed a slightly ellipsoid shape and smooth to shallow groovy surface. The mass of ascocarps ranged from 0.13 g to 15.95 g, and the truffle was composed of 71 % carbohydrates, 19 % protein, 5 % ash, and 5 % of fat. Octan-3-one, 1-methoxy-3-methyl-butane, and 1-methoxy-2-methyl-butane determined T. floridanum characteristic aroma. Soil properties were also specific for this truffle, differing from optimal soils where commercial truffles are produced. In addition, the occurrence of earwigs (Anisolabididae, Anisolabidinae) feeding on truffles (26 % of all ascocarps) in pecan orchards may reduce truffle quality and cause financial losses. T. floridanum aroma has a unique composition, completely different from any commercial and non-commercial truffle species analyzed so far. Soil conditions in pecan orchards were also specific for truffle fruiting. Further studies should elucidate other ecological conditions for the co-production of T. floridanum with pecan.(AU)
Assuntos
Ascomicetos/química , Carya/microbiologia , Ecologia/métodos , Análise do Solo , Inquéritos Nutricionais , Comercialização de ProdutosRESUMO
A 52-year-old pine forest is characterized as an environment with low plant diversity and large accumulation of allelopathic litter with poor nutrient content. Collembola is sensitive to environmental conditions and may have difficulties living in these forests. This study aimed (1) to evaluate the abundance and richness of Collembola in the soil of a 52-year-old pine afforestation with different moisture contents; and (2) to identify the landhopper sampled unintentionally. For sampling, pitfall traps were set up for four days, in areas of a Pinus elliottii afforestation with high and low soil moisture located at the Universidade Federal de Santa Maria. Collembola specimens were counted and identified to family and genus level. The total abundance of springtails was greater in the low soil moisture area. The genera Desoria and Lepidocyrtus, and specimens of the family Onychiuridae were more abundant in low soil moisture, meanwhile, the genus Ceratophysella was more abundant in the high soil moisture. The landhopper Talitroides sylvaticus was sampled unintentionally by traps set up in the soil with higher moisture and calcium content. Six genera of Collembola and the landhopper T. sylvaticus were identified in soil of a P. elliottii afforestation and their distribution is influenced by soil moisture.(AU)
Assuntos
Pinus/parasitologia , Infestações por Pulgas , Sifonápteros/parasitologia , Umidade do Solo , BiodiversidadeRESUMO
BACKGROUND: Ancylostoma species have demanded attention due to their zoonotic potential. The use of anthelmintics is the usual method to prevent environmental contamination by Ancylostoma eggs and larvae. Nematophagous fungi have been widely used in their biological control due to the fungus ability to capture and digest free nematode forms. AIMS: The aim of this study was to evaluate the effect of four different fungal extracts of Paecilomyces lilacinus (n=2), Trichoderma harzianum (n=1) and Trichoderma virens (n=1) isolates on the hatchability of Ancylostoma eggs. METHODS: Fungal extracts consisted of fungal broth culture supernatant without filtration (crude extract) and filtered broth (filtered extract), macerated mycelium (crude macerate), and macerated mycelium submitted to filtration (filtered macerate). The Ancylostoma eggs were obtained from the feces of naturally infected dogs. In vitro assays were performed in five replicates and consisted of four treatments and one control group. RESULTS: The activity of the fungal extracts of each evaluated fungus differed (p<0.05) from those of the control group, showing significant ovicidal activity. The hatching of the eggs suffered reduction percentages of 68.43% and 47.05% with P. lilacinus, and 56.43% with T. harzianum, when crude macerate extract was used. The reduction with the macerate extract of T. virens was slightly lower (52.25%) than that for the filtered macerate (53.64%). CONCLUSIONS: The results showed that all extracts were effective in reducing the hatchability of Ancylostoma eggs. The ovicidal effect observed is likely to have been caused by the action of hydrolytic enzymes secreted by the fungi.
Assuntos
Ancylostoma/efeitos dos fármacos , Agentes de Controle Biológico/farmacologia , Produtos Biológicos/farmacologia , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Paecilomyces , Trichoderma , Ancylostoma/isolamento & purificação , Ancilostomíase/parasitologia , Ancilostomíase/veterinária , Animais , Doenças do Cão/parasitologia , CãesRESUMO
ABSTRACT: Composting and vermicomposting before addition to the soil is a viable alternative to the disposal of cattle manure. However, this residue has been used in the untreated form for seedling production. This study evaluated the use of cattle manure in natura, and the organic composted or vermicomposted variants of cattle manure on substrates used in the production of Eucalyptus urograndis seedlings. The treatments consisted of substrates formulated by mixing the organic fertilizers with washed sand in 20, 40, 60, 80 or 100 (v/v) percentages, compared to a commercial substrate. The E. urograndis seedlings were grown in tubes in a greenhouse and evaluated after 120 days for shoot and root dry weights, plant height, stem diameter, shoot/root ratio, and Dickson quality index. The substrate formulated from a mixture of 80% (v/v) of cattle manure in natura and washed sand allows for better development in Eucalyptus seedlings. Substrate containing 100% bovine manure vermicompost or organic compost produced seedlings with lower quality than in natura bovine manure but superior to the commercial substrate. Due to the health risks associated with use of untreated bovine manure, organic compost and vermicompost are good alternatives for the production of E. urograndis seedlings.
RESUMO: Uma alternativa para destinar corretamente o esterco bovino é realizar a compostagem e/ou vermicompostagem e depois adicioná-lo ao solo como fonte de nutrientes às plantas. Porém, este resíduo tem sido utilizado na produção de mudas sem tratamento. O estudo teve por objetivo avaliar o uso de esterco bovino in natura, de composto orgânico e de vermicomposto, produzidos a partir do esterco bovino, em substratos para a produção de mudas de Eucalyptus urograndis. Os tratamentos constituíram-se dos substratos formulados pela mistura dos fertilizantes orgânicos com areia lavada nas porcentagens de 20, 40, 60, 80 e 100 (v/v), em comparação com um substrato comercial (SC). As mudas de Eucalyptus urograndis foram cultivadas em tubetes, em casa de vegetação, e avaliadas aos 120 dias quanto a massa seca da parte aérea e raiz, altura da planta, diâmetro do caule, relação parte aérea/raiz e índice de qualidade de Dickson. O substrato formulado pela mistura de 80% (v/v) de esterco bovino in natura com areia lavada proporcionou o melhor desenvolvimento das mudas de eucalipto. O substrato contendo 100% de vermicomposto de esterco bovino ou composto orgânico produziu mudas com qualidade inferior ao esterco bovino in natura, mas superior ao substrato comercial. Devido aos riscos à saúde associados ao uso de esterco bovino não tratado, o composto orgânico e o vermicomposto são boas alternativas para a produção de mudas de E. urograndis.
RESUMO
Composting and vermicomposting before addition to the soil is a viable alternative to the disposal of cattle manure. However, this residue has been used in the untreated form for seedling production. This study evaluated the use of cattle manure in natura, and the organic composted or vermicomposted variants of cattle manure on substrates used in the production of Eucalyptus urograndis seedlings. The treatments consisted of substrates formulated by mixing the organic fertilizers with washed sand in 20, 40, 60, 80 or 100 (v/v) percentages, compared to a commercial substrate. The E. urograndis seedlings were grown in tubes in a greenhouse and evaluated after 120 days for shoot and root dry weights, plant height, stem diameter, shoot/root ratio, and Dickson quality index. The substrate formulated from a mixture of 80% (v/v) of cattle manure in natura and washed sand allows for better development in Eucalyptus seedlings. Substrate containing 100% bovine manure vermicompost or organic compost produced seedlings with lower quality than in natura bovine manure but superior to the commercial substrate. Due to the health risks associated with use of untreated bovine manure, organic compost and vermicompost are good alternatives for the production of E. urograndis seedlings.
Uma alternativa para destinar corretamente o esterco bovino é realizar a compostagem e/ou vermicompostagem e depois adicioná-lo ao solo como fonte de nutrientes às plantas. Porém, este resíduo tem sido utilizado na produção de mudas sem tratamento. O estudo teve por objetivo avaliar o uso de esterco bovino in natura, de composto orgânico e de vermicomposto, produzidos a partir do esterco bovino, em substratos para a produção de mudas de Eucalyptus urograndis. Os tratamentos constituíram-se dos substratos formulados pela mistura dos fertilizantes orgânicos com areia lavada nas porcentagens de 20, 40, 60, 80 e 100 (v/v), em comparação com um substrato comercial (SC). As mudas de Eucalyptus urograndis foram cultivadas em tubetes, em casa de vegetação, e avaliadas aos 120 dias quanto a massa seca da parte aérea e raiz, altura da planta, diâmetro do caule, relação parte aérea/raiz e índice de qualidade de Dickson. O substrato formulado pela mistura de 80% (v/v) de esterco bovino in natura com areia lavada proporcionou o melhor desenvolvimento das mudas de eucalipto. O substrato contendo 100% de vermicomposto de esterco bovino ou composto orgânico produziu mudas com qualidade inferior ao esterco bovino in natura, mas superior ao substrato comercial. Devido aos riscos à saúde associados ao uso de esterco bovino não tratado, o composto orgânico e o vermicomposto são boas alternativas para a produção de mudas de E. urograndis.
Assuntos
Esterco/análise , Eucalyptus/crescimento & desenvolvimento , Fertilizantes/análise , Fertilizantes/efeitos adversosRESUMO
Composting and vermicomposting before addition to the soil is a viable alternative to the disposal of cattle manure. However, this residue has been used in the untreated form for seedling production. This study evaluated the use of cattle manure in natura, and the organic composted or vermicomposted variants of cattle manure on substrates used in the production of Eucalyptus urograndis seedlings. The treatments consisted of substrates formulated by mixing the organic fertilizers with washed sand in 20, 40, 60, 80 or 100 (v/v) percentages, compared to a commercial substrate. The E. urograndis seedlings were grown in tubes in a greenhouse and evaluated after 120 days for shoot and root dry weights, plant height, stem diameter, shoot/root ratio, and Dickson quality index. The substrate formulated from a mixture of 80% (v/v) of cattle manure in natura and washed sand allows for better development in Eucalyptus seedlings. Substrate containing 100% bovine manure vermicompost or organic compost produced seedlings with lower quality than in natura bovine manure but superior to the commercial substrate. Due to the health risks associated with use of untreated bovine manure, organic compost and vermicompost are good alternatives for the production of E. urograndis seedlings.(AU)
Uma alternativa para destinar corretamente o esterco bovino é realizar a compostagem e/ou vermicompostagem e depois adicioná-lo ao solo como fonte de nutrientes às plantas. Porém, este resíduo tem sido utilizado na produção de mudas sem tratamento. O estudo teve por objetivo avaliar o uso de esterco bovino in natura, de composto orgânico e de vermicomposto, produzidos a partir do esterco bovino, em substratos para a produção de mudas de Eucalyptus urograndis. Os tratamentos constituíram-se dos substratos formulados pela mistura dos fertilizantes orgânicos com areia lavada nas porcentagens de 20, 40, 60, 80 e 100 (v/v), em comparação com um substrato comercial (SC). As mudas de Eucalyptus urograndis foram cultivadas em tubetes, em casa de vegetação, e avaliadas aos 120 dias quanto a massa seca da parte aérea e raiz, altura da planta, diâmetro do caule, relação parte aérea/raiz e índice de qualidade de Dickson. O substrato formulado pela mistura de 80% (v/v) de esterco bovino in natura com areia lavada proporcionou o melhor desenvolvimento das mudas de eucalipto. O substrato contendo 100% de vermicomposto de esterco bovino ou composto orgânico produziu mudas com qualidade inferior ao esterco bovino in natura, mas superior ao substrato comercial. Devido aos riscos à saúde associados ao uso de esterco bovino não tratado, o composto orgânico e o vermicomposto são boas alternativas para a produção de mudas de E. urograndis.(AU)
Assuntos
Eucalyptus/crescimento & desenvolvimento , Fertilizantes/efeitos adversos , Fertilizantes/análise , Esterco/análiseRESUMO
Eucalypts is one of the main species used for commercial reforestation in the Rio Grande do Sul State, Brazil. This study aimed to evaluate the survival and early growth of eucalyptus trees in an area subject to sandy process after three years of growth. The Eucalyptus grandis seedlings were grown in a greenhouse, inoculated or not with the isolated ectomycorrhizal Pisolithus microcarpus (UFSC-Pt116), produced in peat or Entisol. After 120 days, the seedlings were transplanted to an area subject to the sandy process, in the São Francisco de Assis city, RS. The plants have been evaluated regarding survival, height, stem diameter, nitrogen, phosphorus and potassium levels and total phosphorus, inorganic phosphorus, organic phosphorus and wood production on different days after planting. The seedlings grown on the Entisol which was inoculated with the isolated UFSC-Pt116 presented higher survival rates, height, stem diameter, nitrogen concentration and wood production then non-inoculated seedlings. Inoculation with ectomycorrhizal fungi enhanced the production of E. grandis seedlings in survival rates, height, stem diameter.
Assuntos
Basidiomycota/crescimento & desenvolvimento , Eucalyptus/crescimento & desenvolvimento , Eucalyptus/microbiologia , Micorrizas/crescimento & desenvolvimento , Brasil , Eucalyptus/fisiologia , Desenvolvimento Vegetal , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Plântula/fisiologiaRESUMO
Mycorrhizae are mutualistic associations between fungi and plant roots. These symbiotic associations are abundant and occur in 75 to 80 % of plants. Ectomycorrhizal fungi are very important in ecosystems, because their mutualistic association with plants of different species helps nutrients and water absorption, as well as protection of the host plant against pathogens and abiotic stresses. Most ectomycorrhizal fungi belong to the Basidiomycota class, such as the following genera: Amanita, Hebeloma, Hysterangium, Laccaria, Lactarius, Rhizopogon, Russula, Scleroderma, Suillus, Tricholoma, among others. Morphological studies on ectomycorrhizae report important results in understanding the species biodiversity. However, the use of molecular biology nowadays is indispensable. Among the various molecular tools available, there is consensus about the use of tools based on sequencing of the Internal Transcribed Spacer (ITS) of fungi rDNA, aiding in species characterization and construction of phylogenetic studies. The ITS region is of easy amplification, it has multicopy nature and enables differentiation between species. The objective of this study was to show that the use of molecular biology tools associated with morphotyping to characterize species of ectomycorrhizae is more effective than when they are used on their own.
Assuntos
Micorrizas/genética , Micorrizas/isolamento & purificação , Fungos , Reação em Cadeia da Polimerase , Tipagem MolecularRESUMO
Mycorrhizae are mutualistic associations between fungi and plant roots. These symbiotic associations are abundant and occur in 75 to 80 % of plants. Ectomycorrhizal fungi are very important in ecosystems, because their mutualistic association with plants of different species helps nutrients and water absorption, as well as protection of the host plant against pathogens and abiotic stresses. Most ectomycorrhizal fungi belong to the Basidiomycota class, such as the following genera: Amanita, Hebeloma, Hysterangium, Laccaria, Lactarius, Rhizopogon, Russula, Scleroderma, Suillus, Tricholoma, among others. Morphological studies on ectomycorrhizae report important results in understanding the species biodiversity. However, the use of molecular biology nowadays is indispensable. Among the various molecular tools available, there is consensus about the use of tools based on sequencing of the Internal Transcribed Spacer (ITS) of fungi rDNA, aiding in species characterization and construction of phylogenetic studies. The ITS region is of easy amplification, it has multicopy nature and enables differentiation between species. The objective of this study was to show that the use of molecular biology tools associated with morphotyping to characterize species of ectomycorrhizae is more effective than when they are used on their own.(AU)
Assuntos
Micorrizas/genética , Micorrizas/isolamento & purificação , Fungos , Reação em Cadeia da Polimerase , Tipagem MolecularRESUMO
The Pampa biome is considered one of the main hotspots of the world's biodiversity and it is estimated that half of its original vegetation was removed and converted to agricultural land and tree plantations. Although an increasing amount of knowledge is being assembled regarding the response of soil bacterial communities to land use change, to the associated plant community and to soil properties, our understanding about how these interactions affect the microbial community from the Brazilian Pampa is still poor and incomplete. In this study, we hypothesized that the same soil type from the same geographic region but under distinct land use present dissimilar soil bacterial communities. To test this hypothesis, we assessed the soil bacterial communities from four land-uses within the same soil type by 454-pyrosequencing of 16S rRNA gene and by soil microbial activity analyzes. We found that the same soil type under different land uses harbor similar (but not equal) bacterial communities and the differences were controlled by many microbial taxa. No differences regarding diversity and richness between natural areas and areas under anthropogenic disturbance were detected. However, the measures of microbial activity did not converge with the 16S rRNA data supporting the idea that the coupling between functioning and composition of bacterial communities is not necessarily correlated.
Assuntos
Bactérias/crescimento & desenvolvimento , Ecossistema , Microbiologia do Solo , Bactérias/metabolismo , Sequência de Bases , Biomassa , Brasil , Dióxido de Carbono/metabolismo , Análise de Componente Principal , Solo/químicaRESUMO
Background. Ancylostoma species have demanded attention due to their zoonotic potential. The use of anthelmintics is the usual method to prevent environmental contamination by Ancylostoma eggs and larvae. Nematophagous fungi have been widely used in their biological control due to the fungus ability to capture and digest free nematode forms. Aims. The aim of this study was to evaluate the effect of four different fungal extracts of Paecilomyces lilacinus (n=2), Trichoderma harzianum (n=1) and Trichoderma virens (n=1) isolates on the hatchability of Ancylostoma eggs. Methods. Fungal extracts consisted of fungal broth culture supernatant without filtration (crude extract) and filtered broth (filtered extract), macerated mycelium (crude macerate), and macerated mycelium submitted to filtration (filtered macerate). The Ancylostoma eggs were obtained from the feces of naturally infected dogs. In vitro assays were performed in five replicates and consisted of four treatments and one control group. Results. The activity of the fungal extracts of each evaluated fungus differed (p<0.05) from those of the control group, showing significant ovicidal activity. The hatching of the eggs suffered reduction percentages of 68.43% and 47.05% with P. lilacinus, and 56.43% with T. harzianum, when crude macerate extract was used. The reduction with the macerate extract of T. virens was slightly lower (52.25%) than that for the filtered macerate (53.64%). Conclusions. The results showed that all extracts were effective in reducing the hatchability of Ancylostoma eggs. The ovicidal effect observed is likely to have been caused by the action of hydrolytic enzymes secreted by the fungi (AU)
Antecedentes. Las especies del género Ancylostoma son de gran importancia debido a su potencial zoonótico. El uso de antihelmínticos es el método habitual en la prevención de la contaminación ambiental por huevos y larvas del género Ancylostoma. Los hongos nematófagos se utilizan ampliamente en el control biológico de aquellos, debido a su capacidad de capturar y digerir nematodos libres. Objetivo. El objetivo del estudio fue evaluar el efecto de cuatro extractos diferentes de hongos (Paecilomyces lilacinus [n=2], Trichoderma harzianum [n=1] y Trichoderma virens [n=1]) en la eclosionabilidad de huevos de especies de Ancylostoma. Métodos. Los extractos de hongos constaban del sobrenadante del cultivo en caldo fúngico sin filtración (extracto crudo) y caldo filtrado (extracto filtrado), micelio macerado (macerado crudo) y micelio macerado sometido a filtración (macerado filtrado). Los huevos de Ancylostoma se obtuvieron a partir de heces de perros infectados de manera natural. Se realizaron cinco repeticiones de los ensayos in vitro con cuatro tratamientos y un grupo control. Resultados. La actividad de los extractos fúngicos de cada hongo evaluado difiere (p<0,05) de la de aquellos del grupo control, lo que demuestra una actividad ovicida significativa. Con el extracto crudo macerado, la reducción de la eclosión mostró porcentajes del 68,43 y el 47,05% en el caso de P. lilacinus y del 56,43% para el caso de T. harzianum. El porcentaje de reducción en el uso del macerado crudo en T. virens fue del 52,25%, algo inferior respecto al macerado filtrado (53,64%). Conclusiones. Los resultados mostraron que todos los extractos fueron eficaces en la reducción de la eclosionabilidad de huevos de Ancylostoma. Es probable que el efecto ovicida observado haya sido causado por la acción de enzimas hidrolíticas secretadas por los hongos (AU)
Assuntos
Paecilomyces/isolamento & purificação , Trichoderma/isolamento & purificação , Hypocrea/isolamento & purificação , Ancylostoma/isolamento & purificação , Fungos/isolamento & purificação , Nematoides/isolamento & purificação , Técnicas In Vitro/instrumentação , Técnicas In Vitro/métodos , Técnicas In Vitro/normas , 28573RESUMO
ABSTRACT: This research aimed to evaluate the mineralization of nitrogen (N) and to define the efficiency index (EI) of N after the addition of organic fertilizers based on cattle manure on the soil under laboratory conditions. A completely randomized statistical design with four replicates was used. The treatments were set as follows: T1) Soil (control); T2) Soil + vermicompost of cattle manure (CMV); T3) Soil + cattle manure and straw compost (CMS); and T4) Soil + cattle manure (CM). Experimental units were constituted by acrylic flasks with 5 x 5cm (height x diameter). Each flask was added with 135g of wet soil and 2.20, 2.45 and 2.27g of CMV, CMS and CM, respectively. Treatments were incubated at 25°C and the amount of mineral N from the soil (N-NH4+ and N-NO2- + N-NO3-) was determined at the beginning of the experiment and after 7, 14, 28, 56 and 112 days of incubation. The highest concentration of N-NO2- + N-NO3- in the soil were observed within the CMS treatment. The EI of N was of 27, 23 and 22% for CMS, CMV and CM, respectively. The mineralization of N from organic fertilizers based on cattle manure occurs on its vast majority within the first 28 days after its addition to the soil. The EI of N from the organic fertilizers based of cattle manure was higher for CMS>CMV>CM and achieved only 80% of what expected for organic fertilizers derived from cattle manure.
RESUMO: Este trabalho teve como objetivo avaliar em condição de laboratório a mineralização do nitrogênio (N) e determinar o índice de eficiência (EI) do N após adição de fertilizantes orgânicos a base de esterco bovino no solo. Foi utilizado o delineamento inteiramente casualizado com quatro repetições. Os tratamentos avaliados foram: T1) Solo (testemunha); T2) Solo + vermicomposto de esterco bovino (CMV); T3) Solo + composto de palha e esterco bovino (CMS); e T4) Solo + esterco bovino (CM). As unidades experimentais foram frascos de acrílico com 5cm de altura e 5cm de diâmetro. Em cada frasco, foram adicionados 135g de solo úmido e 2,20, 2,45 e 2,27g de CMV, CMS e CM, respectivamente. Os tratamentos foram acondicionados em incubadora a 25°C e os teores de N mineral do solo (N-NH4+ e N-NO2- + N-NO3-) foram determinados na data de instalação, aos 7, 14, 28, 56 e 112 dias de incubação. Os maiores teores de N-NO2- + N-NO3- no solo foram observados no tratamento CMS. O EI do N foi de 27, 23 e 22% para CMS, CM e CMV, respectivamente. A mineralização do N dos fertilizantes orgânicos a base do esterco bovino ocorre em sua grande maioria nos primeiros 28 dias após sua adição ao solo. O EI do N dos fertilizantes orgânicos a base de esterco bovino foi maior para CMS>CMV>CM e atingem apenas 80% do esperado para fertilizantes orgânicos oriundos de esterco bovino.