Arbuscular mycorrhizal fungi in the soil using cover crops with and without nitrogen addition.

This study aimed to evaluate the occurrence of mycorrhizal fungi and glomalin content in soil under different cover crops with and without the application of nitrogen in the cover. The following cover plants were used: Crotalaria juncea ( L.), wild beans from Ceará ( Mart.

Fire ants: What do rural and urban areas show us about occurrence, diversity, and ancestral state reconstruction?

In South America, Solenopsis saevissima and S. invicta are the most common fire ants. Nests are founded in areas under anthropic interference like urban or rural areas, but S.

Mycorrhizal fungi arbuscular in forage grasses cultivated in Cerrado soil.

The Cerrado is one of the most important regions for agricultural development in the world and is the main productive breadbasket of the Americas. One of the main agricultural activities in the region is high-tech livestock. Cerrado soils are predominantly low in fertility, and arbuscular mycorrhizal fungi play a fundamental role in plant nutrition in this biome.

Resistance of soil to penetration as a parameter indicator of subsolation in crop areas of sugar cane.

Sugarcane is a very important economic crop that relies heavily on agricultural machinery, which contributes to soil compaction and a consequent decline in productivity. Subsoiling operation reduces the problems caused by compression; however, it is necessary to know its location and intensity. Accordingly, the aim of this work is to present a compression diagnostic method based on soil resistance to penetration as the parameter that indicates need for intervention in the subsoil.

Seasonal Variation in Mycorrhizal Community of Different Cerrado Phytophysiomies.

Understanding the dynamics of mycorrhizal fungi in the Cerrado is fundamental for the adoption of conservation practices and for understanding the resilience of this biome in relation to long periods of drought. Thus, this work aimed to verify the dynamics of the mycorrhizal population in five phytophysiognomies of the Cerrado biome. The samples were taken from the Chapada dos Veadeiros National Park, a permanent preservation with native Cerrado vegetation without any anthropic influence.

Streptomyces odonnellii sp. nov., a proteolytic streptomycete isolated from soil under cerrado (savanna) vegetation cover.

A novel streptomycete, strain 594, isolated from Brazilian soil collected under cerrado (savanna) vegetation cover is described. Strain 594 produced thermophilic chitinolytic proteases in assays containing feather meal and corn steep liquor as sole sources of carbon and nitrogen. The strain produced white to grey aerial mycelium and spiral chains of spiny-surfaced spores on the aerial mycelium and did not produce diffusible pigments.

Molecular characterization of fire ants, Solenopsis spp., from Brazil based on analysis of mtDNA gene cytochrome oxidase I.

Species from the Solenopsis saevissima (Smith) (Hymenoptera: Formicidae) species group are native to South America and have a cosmopolitan distribution because they have been accidentally introduced in many countries around the world. In Brazil, they have a wide distribution, including urban areas. The present study was conducted to investigate the characterization of Solenopsis genus populations associated with urban/human interference sites in Brazil by analyzing the mitochondrial gene cytochrome oxidase I and estimating the degree of relatedness of these populations to make inferences about their phylogeny and also observe the patterns of mitochondrial haplotype (mitotype) distribution across their range.

Presence and distribution of the endosymbiont Wolbachia among Solenopsis spp. (Hymenoptera: Formicidae) from Brazil and its evolutionary history.

Wolbachia are intracellular bacteria that commonly infect arthropods. Its prevalence among ants of the genus Solenopsis is high. In the present study, the presence and distribution of these endosymbionts was examined among populations of Solenopsis spp.

[Prevalence and risk factors of human infection by Toxocara canis in Salvador, State of Bahia, Brazil].

Introduction: Larva migrans visceral is caused by Toxocara sp and has never been studied in Bahia. This work investigated the prevalence and risk factors for infection by Toxocara canis in individuals from Salvador, State of Bahia.

Methods: Three hundred and thirty-eight individuals were investigated for the presence of serum IgG anti-T.

Suitability of a transport box for blood sample shipment over a long period.

Background: Safety transport boxes are increasingly used to ship laboratory specimens but there is little information on their capacity to maintain suitable transportation temperatures.

Materials And Methods: Inner temperature was assessed using a commercially available transport box during an 8-h transportation period in the heat.

Results: Temperature stability was unsatisfactory during approximately 64% of the transportation time (i.

Streptomyces lunalinharesii sp. nov., a chitinolytic streptomycete isolated from cerrado soil in Brazil.

A novel chitinolytic actinomycete isolated from a Brazilian cerrado soil, designated strain RCQ1071(T), was assigned to the genus Streptomyces on the basis of chemical and morphological characteristics. The almost-complete nucleotide sequence of the 16S rRNA gene of strain RCQ1071(T) was determined and also placed this strain in the genus Streptomyces. Phylogenetic analyses of 16S rRNA gene sequences showed that strain RCQ1071(T) formed a long branch in a group related to Streptomyces albulus, sharing approximately 98 % sequence similarity.

Streptomyces lunalinharesii spores contain chitin on the outer sheath.

Chitin from Streptomyces lunalinharesii spores, detected on its outermost surface layer, was isolated and characterized by chemical and spectroscopic methods, transmission electron microscopy and flow cytometry analysis. Gold-chitinase- and gold-lectin (Lycopersicum esculentum agglutinin, LEA)-conjugated labels were used in microscopy experiments, whereas a fluorescence-lectin (LEA) conjugate was used in flow cytometry analysis. Chitin isolation consisted of several steps of hot alkali and nitrous acid treatment, and the final material was obtained in the colloidal form.

Production and partial characterization of extracellular proteinases from Streptomyces malaysiensis, isolated from a Brazilian cerrado soil.

Streptomyces malaysiensis AMT-3, isolated from a Brazilian cerrado soil, showed proteolytic activities detected by gelatin-sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The optimum proteinase production was obtained when using 2.5% wheat bran and 0.

A metalloproteinase extracellularly released by Crithidia deanei.

Actively motile cells from a cured strain of Crithidia deanei released proteins in phosphate buffer (pH 7.4). The molecular mass of the released polypeptides, which included some proteinases, ranged from 19 to 116 kDa.

A novel extracellular calcium-dependent cysteine proteinase from Crithidia deanei.

An extracellular cysteine proteinase from an aposymbiotic strain of Crithidia deanei was purified 39-fold by a combination of anion-exchange and gel filtration chromatographies. The native molecular mass of this proteinase was estimated to be 225 kDa by gel filtration chromatography and it migrates in SDS-PAGE as a single band of 80 kDa. The optimal enzymatic activity on gelatin was found to occur in the presence of calcium at a neutral pH and at 28 degrees C.