ABSTRACT: This study aimed to evaluate the relationship of edaphic fauna under a no-tillage system with different levels of soybean productivity [High (NTH), Medium (NTM) and Low (NTL)] in the west of Santa Catarina (Brazil), identifying which chemical and physical variables most affect them, and the best indicators that can be used. Native forest (NF) areas were used as a reference. A total of 207 samples of soil fauna were collected by soil monolith and pitfall trap methods over two years of evaluation in four municipalities. Based on edaphic fauna data, Shannon-Wiener (H’), Pielou (J), Dominance (D), Margalef and Fisher Alpha (α) indices were generated, in addition to the average richness and abundance. Data from NTs were submitted to analysis of variance and compared by Tukey's test (p > 0.05). The NF was used as a reference and compared with the agriculture system by Dunnett test (p > 0.05), and regressions between soybean productivity and diversity indices. The H’, Margalef, α indices, and average richness for soil fauna sampled by soil monoliths followed the productivity gradient NTH > NTM > NTL, showing a positive correlation with the increase of soybean productivity. NTH has a diversity index similar to that of NF. Soybean productivity is affected by the richness and diversity of edaphic fauna, but abundance was not sensitive in predicting treatments under no-tillage; Fisher's alpha index was more sensitive in treatment separation with soil monoliths. The environmental variables aluminum, organic matter, phosphorus, potassium and penetration resistance affect the fauna edaphic.

ABSTRACT: Spiders are part of the soil biodiversity, considered fundamental to the food chain hierarchy, directly and indirectly influencing several services in agricultural and forest ecosystems. The present study aimed to evaluate the biodiversity of soil spider families and identify which soil properties influence their presence, as well as proposing families as potential bioindicators. Native forest (NF) and reforested sites (RF) with Araucaria angustifolia (Bertol.) Kuntze were evaluated in three regions of the state São Paulo, both in the winter and summer. Fifteen soil samples were collected from each forest to evaluate the biological (spiders and microbiological), chemical and physical soil properties, in addition to properties of the litter (dry matter and C, N and S contents). For soil spiders, two sampling methods were used: pitfall traps and soil monoliths. In total, 591 individuals were collected, and distributed in 30 families, of which 306 individuals (22 families) came from pitfall traps and 285 individuals (26 families) from monoliths. Only samples obtained by the monolith method revealed seasonal differences in the mean density and richness of spiders between NF and RF. Canonical discriminant analysis showed the separation of these forests of Araucaria. Principal Component Analysis demonstrated the correlation of a number of spider families with certain soil properties (organic carbon, basal respiration, metabolic quotient, litter carbon, total porosity, bulk density and soil moisture). We identified 10 families (Anapidae, Corinnidae, Dipluridae, Hahniidae, Linyphiidae, Lycosidae, Nemesiidae, Palpimanidae, Salticidae, Scytodidae) that contributed most to separating native forest from the replanted forest, indicating the possibility of the spiders being used as bioindicators.

Resumo Os agrotóxicos são amplamente utilizados no setor agrícola para o controle e prevenção contra pragas e doenças. O uso desses produtos é capaz de afetar de maneira negativa organismos não-alvos de papel significante no solo, como as minhocas. O presente trabalho teve como objetivo avaliar a toxicidade da formulação comercial do fungicida Comet® (ingrediente ativo - i.a. piraclostrobina) nas concentrações: 0,08; 0,17; 0,35; 0,70; 1,40 e 2,80 mg da formulação comercial kg-1 solo e do fungicida + inseticida Standak®Top (i.a. piraclostrobina + tiofanato metílico + fipronil) nas concentrações: 0,05; 0,10; 0,20; 0,60; 1,20 e 2,40 mg mg da formulação comercial kg-1 solo, acrescido do tratamento controle, sobre a espécie Eisenia andrei em Solo Artificial Tropical (SAT), por meio de ensaios padronizados. As concentrações dos produtos testados não foram suficientes para causar a letalidade dos organismos. Entretanto, nas primeiras concentrações de ambos os produtos (0,08 e 0,05 mg kg-1 solo) foram observados efeitos de redução nas taxas reprodutivas dos organismos, com valor de CE50 4,51 mg kg-1 solo (< 0,05-20,94) para a formulação comercial do produto de efeito fungicida + inseticida. Os efeitos de redução nas taxas de reprodução podem afetar a perpetuação desses organismos no ecossistema solo à longo prazo, afetando processos importantes como a decomposição de matéria orgânica e ciclagem de nutrientes.

Abstract Pesticides are widely used in the agricultural sector to control and prevent pests and diseases. The use of these products can adversely affect non-target organisms that have a significant role in the soil, such as earthworms. This study evaluated the toxicity of the commercial formulation of the fungicide Comet® (active ingredient - a.i. pyraclostrobin) at concentrations of 0.08, 0.17, 0.35, 0.70, 1.40 and 2.80 mg of the commercial formulation kg-1 soil and the fungicide + insecticide Standak®Top (a.i. pyraclostrobin + thiophanate-methyl + fipronil) at concentrations of 0.05, 0.10, 0.20, 0.60, 1.20 and 2.40 mg of the commercial formulation kg-1 soil, plus the control treatment, to Eisenia andrei in Tropical Artificial Soil (TAS) by means of standardized tests.

Abstract This study aimed to evaluate the abundance and diversity of Coleoptera in five land use systems (LUS) and the soil properties that explain the distribution of these organisms. Uses involved native forest (NF), Eucalyptus plantation (EP), perennial pasture (PA), integrated crop-livestock (ICL) and no-tillage (NT) in western Santa Catarina, Brazil. Coleopterans were sampled by the methods of pitfall traps and soil monoliths during the winter and summer. Regardless of the LUS, 1,441 individuals were captured, with Staphylinidae being the most representative family (~47%). The use of NF showed higher abundances of coleopterans. The land use systems PA, NT, and ICL obtained high values of diversity of Coleoptera families, depending on the method and season of collection. The distribution of families was influenced by the sampling season, and some soil properties such as biopores, water content and phosphorus can explain the variation of abundance among the LUS.

ABSTRACT: In recent years, various studies and development using nanoparticles (NPs) have been carried out in the most diverse areas of knowledge. Although nanomaterials are widely employed by many sectors and some may have a fertilizing potential, little is known about their effects on the environment. This study aimed to evaluate the effect of applying, in tropical natural soil, different contents of nanoparticles of zinc oxide (NPs-ZnO) and non-nano zinc oxide (ZnO) on soil pH and on the survival and reproduction rates of earthworms ( Eisenia andrei ) and springtails ( Folsomia candida ) through standardized ecotoxicological tests. The tests used a tropical soil representative of Brazil, classified as Entisol ( Neossolo Quartzarênico órtico típico ) with no history of agricultural use, collected in the 0.00-0.20 m layer, previously sieved (2-mm mesh) and defaunated. The experimental design was completely randomized, and treatments consisted of two forms of zinc (Zn), NPs-ZnO and ZnO, at the following doses: 0, 50, 100, 200, 400, 800, 2,000, and 4,000 mg kg−1. Standardized ecotoxicological tests showed no toxicity of NPs-ZnO in terms of lethality of E. andrei and F. candida . In E. andrei reproduction tests, NPs-ZnO were toxic at doses higher than 400 mg kg−1 (EC50 of 1,021 mg kg−1). Tests with F. candida demonstrated that its reproduction rate was significantly affected by NPs-ZnO at a rate of 4,000 mg kg−1 (EC50 of 3,636 mg kg−1). When used in Entisol, the NPs-ZnO inhibit the reproduction of earthworms and springtails; earthworms are more sensitive to such an effect, it being demonstrate at lower contents than those found for springtails.

Resumo: O objetivo deste estudo foi avaliar a influência do uso do solo na diversidade morfológica de colêmbolos e verificar a relação destes organismos com os atributos físicos, químicos e microbiológicos do solo. Foram coletadas amostras na região Sul de Santa Catarina, envolvendo três municípios: Orleans, Lauro Müller e Siderópolis, nos sistemas de uso do solo (SUS) de floresta nativa (FN), reflorestamento de eucalipto (RE), pastagem perene (PA), integração lavoura-pecuária (ILP) e plantio direto (PD). As coletas de solo para determinação dos atributos edáficos e a instalação de armadilhas de queda, foram realizadas no inverno e verão, nos mesmos pontos. Os colêmbolos coletados foram contados e morfotipados e os dados foram analisados por meio da abundância, diversidade de Shannon-Wiener (H') e Margalef, índice de dominância de Simpson (D), uniformidade de Pielou (J), riqueza de morfotipos e Análise de Componentes Principais (ACP). Os morfotipos de Collembola foram influenciados pelas condições de manejo de cada sistema, sobretudo o impacto dos SUS nesses organismos depende da intensidade das práticas florestais/agrícolas utilizadas, incluindo rotações culturais e preparo do solo.

Abstract: The aim of this study was to evaluate the influence of soil use on the morphological diversity of springtails and to verify the relationship of these organisms with soil physical, chemical, and microbiological properties. Samples were collected in the Southern region of Santa Catarina, involving three municipalities: Orleans, Lauro Müller, and Siderópolis, in the land use systems (LUS) of native forest (NF), Eucalyptus plantation (EP), pasture (PA), integrated crop-livestock (ICL), and no-tillage (NT). Soil samples to determine edaphic properties and pitfall traps were collected in winter and summer, in the same areas. The collected springtails were counted and morphotyped and the data were analyzed through abundance, Shannon-Wiener diversity (H') and Margalef index, Simpson dominance index (D), Pielou evenness index (J), morphotype richness, and Principal Components Analysis (PCA). Springtails morphotypes were influenced by the management conditions of each system, especially the impact of LUS on these organisms depends on the intensity of the forest/agricultural practices used, including crop rotation and soil preparation.

Resumo: O objetivo deste trabalho foi avaliar a qualidade do solo de florestas nativas, reflorestamento de eucalipto, pastagem, sistemas de integração lavoura-pecuária e plantio direto, correlacionando a diversidade morfológica de colêmbolos com propriedades físicas e químicas do solo. Amostras de colêmbolos foram coletadas de solos do planalto sul do Estado de Santa Catarina no Brasil, durante o inverno e o verão, usando armadilhas de queda, em grade amostral de 3 × 3. A morfotipagem dos colêmbolos consistiu na observação de cinco características e para cada uma foi atribuído um valor parcial do índice eco-morfológico para a obtenção do Índice de Qualidade do Solo modificado. As avaliações foram da abundância e diversidade de morfotipos e de atributos físicos (umidade do solo, densidade do solo, bioporos, microporosidade e macroporosidade) e químicos do solo (pH em água, relação cálcio/magnésio e carbono orgânico total), descrevendo os resultados por análises de variância e multivariada. A abundância e a diversidade de colêmbolos foram influenciadas pelos diferentes sistemas de uso do solo. Maior índice de qualidade do solo foi determinado em floresta nativa seguida de reflorestamento de eucalipto, pastagem, plantio direto e integração lavoura-pecuária, no inverno. Além disso, encontrou-se maior índice de qualidade do solo em floresta nativa seguida de integração lavoura-pecuária, reflorestamento de eucalipto, plantio direto e pastagem, no verão. Portanto, o índice de qualidade do solo pode ser avaliado pelas características morfológicas de colêmbolos em correlação com as propriedades físicas e químicas, como razão cálcio/magnésio, teores de carbono orgânico total, bioporos, macroporosidade, microporosidade, umidade do solo, densidade do solo e pH.

Abstract: The aim of this work was to evaluate the soil quality of native forest, eucalyptus plantations, pasture, integrated crop-livestock, and no-tillage systems, correlating the morphological diversity of springtails with physical and chemical soil properties. Springtail samples were captured from soils of the southern plateau of the State of Santa Catarina in Brazil, during winter and summer, by using Pitfall traps, using a 3 × 3 point grid. The morphotyping of springtails consisted of the observation of five traits and for each one a partial value of the eco-morphological index was assigned to obtain the modified Soil Quality Index. A correlation of the morphotype abundance and diversity with physical (soil moisture, bulk density, biopores, microporosity, and macroporosity) and chemical (pH in water, calcium/magnesium ratio and total organic carbon content) soil properties was studied, describing all results by variance and multivariate analyses. The springtail abundance and diversity were influenced by the different land use systems. Higher soil quality index was determined in native forest followed by eucalyptus plantations, pasture, no-tillage system and integrated crop-livestock, in the winter. Moreover, higher soil quality index was found in native forest followed by integrated crop-livestock, eucalyptus plantations, no-tillage system and pasture, in the summer. Therefore, the quality index of a soil can be evaluated by the springtail morphological traits in correlation with the physical and chemical properties such as calcium/magnesium ratio, total organic carbon contents, biopores, macroporosity, microporosity, soil moisture, bulky density and pH.

Resumo: O Brasil sempre foi um dos mais importantes países produtores de café. Ultimamente, houve um renovado interesse pelos sistemas alternativos de produção de café. O Estado do Espírito Santo é o segundo maior produtor de café do Brasil; então, utilizaram-se plantações locais de café para avaliar as relações entre a macrofauna do solo e as propriedades químicas e microbiológicas do solo para identificar quais dessas propriedades discriminam mais efetivamente entre o sistema de manejo orgânico (SO) e o sistema de manejo convencional (SC) das plantações de café. Para cada um desses dois sistemas de cultivo, escolheu-se três fazendas de café que empregaram ambos os sistemas de cultivo e selecionaram os campos mais similares de cada propriedade. Em cada local, primeiro amostrou-se a serrapilheira do solo. Posteriormente, amostraram-se nove monólitos de solo para avaliar a macrofauna, tanto no verão como no inverno. Também, foram coletadas nove amostras suplementares de solo, a alguns centímetros dos monólitos de solo, para análises químicas e microbiológicas. A densidade da macrofauna foi avaliada por ANOVA e análise multivariada. As propriedades químicas e microbiológicas são variáveis ambientais, enquanto os dados sobre a macrofauna são as variáveis explicativas. O número total de indivíduos recuperados neste estudo foi de 3.354 e o clima, identificado pela época de amostragem, foi um ótimo modulador da macrofauna, com maiores números no inverno. A análise dos componentes principais mostrou que a umidade do solo, matéria orgânica, nitrogênio, fósforo, boro, cobre, pH, fosfatases ácido e alcalina e carbono da biomassa microbiana, foram os mais destacados para discriminar ambos os sistemas de cultivo. Encontraram-se diferenças significativas na densidade da macrofauna entre SO e SC, provavelmente devido a uma grande variabilidade geral, uma vez que houve uma tendência para valores muito maiores no SO. Detectou-se a interferência das propriedades químicas e microbiológicas do solo na comunidade de macrofauna em ambos os sistemas de cultivo de café, e alguns resultados claramente correlacionados muito melhor com os dados climáticos do que com outros fatores. A nosso conhecimento, esta é a primeira vez em que os dados apontam para uma clara separação entre a macrofauna do solo mais numerosa e diversificada em café com cultivo orgânico de que com um sistema de cultivo convencional.

Abstract: Brazil has always been one of the most important coffee producing countries. Lately, there has equally been a renewed interest in alternative coffee production systems. The state of Espírito Santo is the second greatest coffee producer in Brazil; so, we used local coffee plantations to evaluate the relations between soil macrofauna and chemical and microbiological soil properties to identify which of these properties discriminate more effectively between the organic management system (OS) and the conventional management system (CS) of coffee plantations. For each of these two cultivation systems we chose three coffee farms who employed both cultivation systems and picked out the most similar fields from each property. At each site, first we sampled the litter at the soil surface. Afterwards, we sampled nine soil monoliths to evaluate the macrofauna, in summer and winter. We also collected nine supplemental soil samples, taken at a few centimeters from the soil monoliths, for chemical and microbiological analyses. Macrofauna density was evaluated by ANOVA and multivariate analysis. The chemical and microbiological properties are environmental variables, while the data on macrofauna are the explanatory variables. The total number of individuals recovered in this study was 3,354, and the climate, identified by the sampling season, was a great modulator of macrofauna, with higher numbers in winter. The principal components analysis showed that soil moisture, organic matter, nitrogen, phosphorus, boron, copper, pH, acid and alkaline phosphatases and microbial biomass carbon, were the most outstanding ones to discriminate both cultivation systems. We found no statistical significant differences in macrofauna density between OS and CS, probably due to a general great variability, since there was a tendency for much greater values in OS. We detected the interference of chemical and microbiological soil properties on the macrofauna community in both systems of coffee cultivation, and some results clearly correlated much better with climate data than with other factors. To our knowledge, this is the first time in which the data point to a clear separation between the more numerous and diversified soil macrofauna in coffee with organic cultivation from that with a conventional cultivation system.

ABSTRACT: Springtails (Collembola) are soil organisms with wide morphological diversity and are sensitive to alterations in the soil, regardless of whether they are human-caused or not. The aim of this study was to evaluate the influence of land use on the morphological diversity of springtails and verify their relationships with soil physical, chemical, and microbiological properties. Samples were collected in the eastern region of Santa Catarina, in three municipalities: Joinville, Blumenau, and Timbó. They included the following land use systems (LUSs): native forest (NF), Eucalyptus plantation (EP), pasture (PA), integrated crop-livestock (ICL), and no tillage (NT). Samples were collected to determine soil properties, and pitfall traps were set in the winter and summer at the same points. The captured springtails were counted and morphotyped, observing features such as presence or absence of ocelli and setae, pigmentation, antenna length, and furcula length. The data were analyzed based on abundance, the Shannon-Wiener (H') and Margalef diversity indices, Pielou's evenness index (J), morphotype richness, modified Soil Biological Quality index (QBS), and Principal Component Analysis (PCA). Springtails abundance was higher in ICL and PA, whereas morphotype richness was higher in NF and ICL in the winter. The Shannon-Wiener and Margalef indices were higher in the winter in NF. In the summer, only H' differed significantly among the LUSs and was higher in NF. The QBS values did not precisely follow the human intervention gradient in either of the two periods. The PCA showed difference among the periods and LUSs. In the winter, the occurrence of morphotypes was related to soil microbiological and chemical properties, whereas in the summer, the distribution of morphotypes was explained by soil physical and chemical properties. Morphological diversity analysis is a good alternative to study springtail distribution and soil biological quality, especially when associated with multivariate techniques.

ABSTRACT Coleopterans (Coleoptera) are major ecosystem service providers. However ecomorphological features that are comparable in a wide range of invertebrates within this group and in various environments must be found, to be able to study regions with different species, contributing to overcome difficulties of the taxonomic approach and understand the functioning of ecosystems. This research addressed the diversity of Coleoptera, using a methodology of ecomorphological traits, as well as their relation with the land use systems (LUS) and the soil properties. The following LUS were evaluated: no-tillage (NT), crop-livestock integration (CLI), pasture (PA), Eucalyptus stands (EST), and native forest (NF). Samples were collected using a 3 × 3 point grid (sampling points at a distance of 30 m), in winter and summer, in three municipalities on the Southern Santa Catarina Plateau, Brazil. Coleopterans were collected using the methodology recommended by the Tropical Soil Biology and Fertility Program, based on the excavation of soil monoliths, and on pitfall traps. To evaluate the biological forms (morphotypes) and ecomorphological groups, the ecomorphological index (EMI) methodology was adopted and the modified soil biological quality (SBQ) index was determined. At the same points, samples were collected to evaluate environmental variables (soil physical, chemical, and microbiological properties). Density data underwent nonparametric univariate statistical analysis and multivariate abundance to verify the distribution of coleopterans in the LUS, and the environmental variables were considered as explanatory. Regardless of the LUS, 14 morphotypes were identified, and adult coleopterans with epigean morphologic adaptations were more abundant than hemi-edaphic and edaphic coleopterans, respectively. Morphotype diversity was higher in the systems NF, EST, and PA in summer and in NT in winter. The reductions in SBQ index were not associated with a gradient of land use intensification (NF> EST> PA> CLI> NT), and the index was higher for NF and lower for EST. Principal component analysis (PCA) indicated a different distribution of invertebrates between the LUS. For the edaphic species, better adapted to life in the soil, a relation with NT and CLI was observed, due to more favorable pH values and phosphorus content. In the NF, a greater amount of morphotypes was identified, and the properties related to soil carbon dynamics contributed to explain this distribution. Separation at the morphotype level, taking adaptation level to soil life into consideration, has proved efficient to discriminate the LUS, mainly along with other explanatory environmental variables.

ABSTRACT: Collembolan species are differently affected by soil tillage (conventional, minimum tillage, and no-tillage) and are known to modify plant growth. This study relies on the relationships between Collembola community structures and land use systems as a proxy for characterizing changes in soil quality. Thus, Collembola community structure (eco-morphological groups - edaphic, hemiedaphic and epigeic, and morphotypes) were examined in a no-tillage system and crop-livestock integration system to evaluate the discriminative power of the Collembola community structure and to determine which soil properties drives structural diversity. Thirty-eight morphotypes of Collembola were recorded in this study, 11 belonging to the edaphic eco-morphological group, 14 hemiedaphic, and 13 epigeic. The hemiedaphic and epigeic groups, in the no-tillage system, were more influenced by changes in soil properties (total organic carbon, particulate organic carbon, total N, Ca, Mg, moisture, bulk density) and mycelium length than the groups in the crop-livestock integration system (mycorrhizal inoculum potential, and soil properties as dehydrogenase, particulate organic carbon, Mg, sand). Collembola eco-morphological groups were better predictors for ecosystem functioning than Collembola density and can be used to distinguish differences between soil uses, reducing laboratory analysis time.

RESUMO O descarte de grandes quantidades de resíduos de mineração de carvão modifica quimicamente o solo e isso pode alterar a estrutura e atividade da fauna edáfica. Objetivou-se estudar os efeitos ecotoxicológicos das deposições de resíduo piritoso (carvão mais a pirita) em dois solos, coletados em Santa Catarina, Argissolo Vermelho-Amarelo e Nitossolo Háplico, nas doses de 0; 2,5; 5; 10 e 20 % desse resíduo. Os testes realizados foram sobrevivência e reprodução de Enchytraeus crypticus e de germinação comAvena sativa e Lotus corniculatus. O valor de pH, independentemente do tipo do solo, diminuiu à medida que aumentou a dose de resíduo piritoso. O resíduo piritoso na menor dose resultou em efeitos negativos ao E. crypticus, como redução na taxa sobrevivência de adultos e nenhuma reprodução. Nos testes de sobrevivência e reprodução de enquitreídeos, o valor de LC50 (concentração estimada que pode causar efeitos negativos na sobrevivência e germinação em 50 % de um grupo de organismos) ficou abaixo 4 % e EC50 (efeitos negativos na reprodução) <2,5 % para os dois solos, respectivamente. A exposição de A. sativa aos dois solos não expressou efeito tóxico para L. corniculatus, no Nitossolo. Porém, no Argissolo, a contaminação causou efeitos na menor dose para L. corniculatus. No teste de germinação de sementes, somente L. corniculatus apresentou sensibilidade no Argissolo Vermelho-Amarelo (LC50<4 %). A elevada sensibilidade dos organismos do solo avaliado à aplicação do resíduo piritoso influenciou-os negativamente, tanto em um curto período de tempo quanto em longo prazo.

ABSTRACT The disposal of large amounts of coal mining waste chemically modifies the soil, and this may change the structure and activity of soil fauna. The objective of this investigation was to study the ecotoxicological effects of depositions of pyritic waste (coal plus pyrite) in two soils collected in Santa Catarina, Argissolo Vermelho-Amarelo (Ultisol) e Nitossolo Háplico (Hapludox), at the application rates of 0, 2.5, 5, 10, and 20 % of that residue. Survival and reproduction of Enchytraeus crypticus and germination of Avena sativa and Lotus corniculatus were tested. The pH value, regardless of the type of soil, decreased as the rate of pyritic waste increased. Pyritic waste at the lowest rate resulted in negative effects on E. crypticus, as shown by reduction in the adult survival rate and no reproduction. In survival and reproduction testing of enchytraeids, the value of LC50 (estimated concentration that can cause negative effects on the survival and germination of 50 % of a group of organisms) was below 4 %, and EC50 (negative effects on reproduction) was less than 2.5 % for both soils. Exposure of A. sativa to the two soils did not have a toxic effect, nor did exposure of L. corniculatus to Hapludox. However, in the Ultisol, contamination caused effects at the lowest rate for L. corniculatus. In the seed germination test, only L. corniculatus showed sensitivity in the Ultisol (LC50<4 %). High sensitivity to the application of pyritic residue adversely affects soil organisms, both in the short term and long term.

RESUMO O nitrogênio é um dos macronutrientes essenciais aos seres vivos, o que o torna um dos fatores limitantes para o crescimento vegetal. Apenas uma parcela dos procariotos, os diazotróficos, possui a capacidade de reduzir o nitrogênio atmosférico para outras formas disponíveis às plantas. A bracatinga é uma espécie arbórea de importância econômica capaz de estabelecer simbiose mutualística com organismos diazotróficos, sendo os seus principais usos: produção de energia, madeira, forragem, indústria química de produtos naturais, apicultura, paisagismo e sombreamento e recuperação de áreas degradadas e zonas ripárias. Este estudo objetivou estabelecer relação entre a diversidade cultural e morfológica e a variabilidade genética dos isolados nodulantes em bracatinga de diferentes condições edafoclimáticas. Coletaram-se nódulos radiculares retirados ao acaso em sete áreas compreendidas entre o Vale do Itajaí, Planalto Sul e Meio-Oeste do Estado de Santa Catarina. Foi observada ampla diversidade cultural entre os diazotróficos presentes, havendo predomínio de isolados de rápido crescimento, de colônia com coloração branca leitosa, formato circular, borda lisa e superfície mucoide. Entre os parâmetros avaliados, a transparência da colônia, a produção de muco e a alteração do pH foram considerados relevantes para a diferenciação dos isolados. A caracterização taxonômica dos isolados foi realizada por comparação dos fragmentos sequenciados, sendo as espécies isoladas deste conjunto amostral pertencentes aos gêneros Burkholderia, Pantoea, Pseudomonas e Rhizobium.

ABSTRACT Nitrogen is one of the essential macronutrients for living beings, which makes it one of the limiting factors for plant growth. Only a portion of the prokaryotes, the diazotrophics, has the ability to reduce atmospheric nitrogen to otherforms available to plants. Bracatinga is an economically important arboreal species capable of establishing mutualistic symbiosis with diazotrophic organisms. Its main uses are: energy production, wood, forage, chemical industry of natural products, beekeeping, landscaping and shadowing and recovery of degraded areas and riparian zones. The present study aimed to establish relationship between cultural and morphological diversity and genetic variabilityfrom nodules of bracatinga isolated in different edaphoclimatic conditions. Root nodules randomly collectedfrom seven areas between the Vale do Itajaí, Plateau South and Midwest of the State of Santa Catarina. Broad cultural diversity was observed among the present diazotrophics, and there was a predominance of fast-growing isolates of colony with milky white coloration, round shape, flat edge and mucoid surface. Among the evaluated parameters, transparency of the colony, mucus production and pH modification were considered relevant to the differentiation of isolates. Taxonomic characterization of the isolates was performed by comparison of the sequenced fragments, being the isolated species of this sample setfrom the genera Burkholderia, Pseudomonas, Pantoea and Rhizobium.

O estudo foi realizado na safra agrícola 2007/08, em um Planossolo Háplico, em Pelotas, Rio Grande do Sul (RS). Os tratamentos compreenderam as cultivares de mamoneira 'AL Guarany 2002' e 'Lyra', com cinco doses de P (0; 30; 60; 90 e 120kg ha-1 de P2O5), sendo dispostas em delineamento blocos ao acaso, em esquema fatorial, com três repetições. Avaliaram-se o estado nutricional e o desempenho produtivo da cultura. A adubação fosfatada alterou os teores foliares de N, Ca, B e Fe da mamoneira; para boro, o efeito restringiu-se à 'Lyra'. A cultivar 'AL Guarany 2002' mostrou-se mais exigente em fósforo que a 'Lyra'. A adubação fosfatada elevou a produtividade de grãos de ambas as cultivares de mamoneira. Esta aumentou com o uso de até 156kg ha-1 de P2O5, para a 'AL Guarany 2002', e de até 90kg ha-1 de P2O5, para a 'Lyra', e as doses de máxima eficiência econômica para essas cultivares foram, respectivamente, de 134kg ha-1 e 78kg ha-1 de P2O5.

The study was carried out from April 2007 to May 2008, on a Planossolo Háplico (Albaqualf), in Pelotas, RS, Brazil. The treatments comprised the castor bean cultivars 'AL Guarany 2002' and 'Lyra', with five rates of phosphate (0; 30; 60; 90 and 120kg ha-1 of P2O5).These were arranged as a randomized complete block in a factorial design with three replications. Castor bean nutritional status and yield performance were evaluated. The phosphate fertilization altered castor bean foliar concentrations of nitrogen, calcium, boron, and iron. For boron, this effect was limited to the 'Lyra' cultivar. The 'AL Guarany 2002' cultivar demanded more phophorus than 'Lyra' cultivar. Phosphate fertilization increased grain yield of both castor bean cultivars. Yield increased with the use of up to 156kg ha-1 of P2O5, for 'AL Guarany 2002' cultivar, and of up to 90kg ha-1 of P2O5, for 'Lyra' cultivar. The rates of maximum economic efficiency for 'AL Guarany 2002' and 'Lyra' cultivars were, respectively, 134kg ha-1 and 78kg ha-1 of P2O5.