Interação competitiva e nível de dano econômico de azevém daninho emhíbridos de canola / Competitive interaction and economic damage level of ryegrass harmfulg in canola hybrids

Na canola ocorrem perdas de produtividade e da qualidade de grãos em função da interferência causada pelo azevém (Lolium multiflorum). Diante disso, objetivou-se avaliar a interferência e identificar variáveis explicativas visando determinar o nível de dano econômico (NDE) de diferentes densidades do azevém infestante de híbridos de canola. O experimento foi instalado em delineamento de blocos casualizados, com uma repetição. Os tratamentos foram compostos pelos híbridos de canola (Hyola 433, Hyola 61, Alht B4, Hyola 575 CL e Hyola 76) e 12 densidades de azevém, de 0 até 260 plantas m-2, em competição com a cultura. Avaliou-se aos 50 dias após a emergência das plantas as variáveis densidades de plantas, área foliar, cobertura de solo e massa seca da parte aérea do azevém. A produtividade de grãos, custo de controle, preço de grãos e eficiência de controle foram determinados na canola. A cobertura do solo apresentou melhor ajuste ao modelo da hipérbole retangular estimando adequadamente as perdas de produtividades de grãos pela interferência do azevém. Os híbridos de canola Hyola 433, Hyola 575 CL e Hyola 76 foram os mais competitivos ao se comparar com os demais na presença do azevém, porém demonstraram as menores produtividades de grãos e também os que apresentaram os maiores valores de NDE. Os híbridos de canola Hyola 433 e Hyola 575 CL apresentaram os maiores valores de NDE com 3,85 a 5,13 plantas m-2 em todas as simulações realizadas, respectivamente. Os menores valores de NDE foram obtidos com os híbridos Hyola 61, Alht B4 e Hyola 76 com variações médias de 1,02 à 2,15 plantas m-2, respectivamente. A produtividade de grãos de canola, o preço da saca, a eficiência do herbicida e a redução no custo de controle, causam variação dos valores do NDE.(AU)

In canola, yield and grain quality losses occur due to the interference caused by ryegrass (Lolium multiflorum) when infesting the crop. Thus, the objective was to evaluate the interference and identify explanatory variables seeking to determine the level of economic damage (NDE) of different densities of ryegrass infesting canola hybrids. The experiment was carried out in a randomized block design, with one replication. The treatments consisted of five canola hybrids (Hyola 433, Hyola 61, Alht B4, Hyola 575 CL and Hyola 76) and 12 ryegrass densities, from 0 to 260 plants m-2, in competition with the crop. At 50 days after plant emergence, the variables as plant densities, leaf area, soil cover and shoot dry matter of ryegrass plants were evaluated. Grain yield, control cost, grain price and control efficiency were determined in canola plants. The soil cover presented the best fit to the rectangular hyperbola model, adequately estimating the grain yield losses due to ryegrass interference. The canola hybrids Hyola 433 and Hyola 575 CL were the most competitive when compared to the others in the presence of the competitor, with higher values of EDL. The canola hybrids Hyola 433 and Hyola 575 CL showed the highest EDL values with 3.85 to 5.13 plants m-2in all simulations performed, respectively. The lowest EDL values were obtained with hybrids Hyola 61, Alht B4and Hyola 76 with average variations of 1.02 to 2.15 plants m-2, respectively. The canola grain yield, grain bag price, efficiency of the herbicide, and the reduction in the control cost cause variation in the economic damage level values.(AU)

Competitive ability of soybean cultivars with Ipomoea indivisa / Habilidade competitiva de cultivares de soja com Ipomoea indivisa

Among the weeds that infest soybeans, the morning glory (Ipomoea indivisa) stands out for competing with water, light, nutrients and also interfering in the crop harvesting process. The aim of this study was to test the competitive ability of soybean cultivars in the presence of I. indivisa, in substitutive experiments. The experiments were carried out in a completely randomized design, with four replicates, using the soybean cultivars M 5838, DM 53i54, DM 57i52, DM 66i68, NS 5445, and NS 6601. A constant final yield for soybean and I. indivisa was observed with 24 plants per pot. Relative and total productivities were analyzed using diagrams applied to substitutive experiments with soybean and I. indivisa plants proportions of 24:0, 18:6, 12:12, 6:18, and 0:24 plantspot-1(crop:weed). On 35 days after the emergence of the culture and the I. indivisa, the morphophysiological characteristics of the plants were assessed and the relative competitiveness indices were calculated considering the 50:50 plant ratio (12:12 plantspot-1). Morning glory affected the morphophysiological characteristics of soybean cultivars, demonstrating superior competitive ability for environmental resources. There wasa competition between soybean cultivars and I. indivisa, which caused reductions in the shoot dry matter for both species. In this study, interspecific competition was more harmful than intraspecific competition.

Dentre as plantas daninhas que infestam a soja, a corda-de-viola (Ipomoea indivisa) se destaca por competir por água, luz, nutrientes e também interferir no processo de colheita da cultura. O objetivo deste trabalho foi testar a habilidade competitiva de cultivares de soja na presença de I. indivisa, em experimentos substitutivos. Os experimentos foram conduzidos em delineamento inteiramente casualizado, com quatro repetições, utilizando as cultivares de soja M 5838, DM 53i54, DM 57i52, DM 66i68, NS 5445 e NS 6601. Observou-se produtividade final constante para soja e I. indivisa com 24 plantas por vaso. As produtividades relativa e total foram analisadas por meio de diagramas aplicados a experimentos substitutivos com plantas de soja e I. indivisanas proporções de 24:0, 18:6,12:12, 6:18 e 0:24 plantasvaso-1 (cultivar:planta daninha) . Aos 35 dias após a emergência da cultura e da I. indivisa, foram avaliadas as características morfofisiológicas das plantas e calculados os índices de competitividade relativa considerando a proporção de plantas de 50:50 (12:12 plantas vaso-1). A corda-de-viola afetou as características morfofisiológicas das cultivares de soja, demonstrando superior capacidade competitiva por recursos ambientais. Houve competição entre as cultivares de soja e I. indivisa, o que ocasionou reduções na matéria seca da parte aérea para ambas as espécies. Neste estudo, a competição interespecífica foi mais prejudicial do que a competição intraespecífica

Interference and economic damage level of alexandergrass in beans as a function of plant density / Interferência e nível de dano econômico de papuã em feijoeiro em função da densidade de plantas

The study of bean sowing density and the level of economic damage (EDL) caused by alexandergrass (Urochloa plantaginea) are important tools for adequately adopting the integrated management of this weed and, thus, producing food with higher quality and less pesticide residue. Therefore, the objective of this work was to evaluate the interference and the level of the economic damage of alexandergrass in competition with the common bean, estimated as a function of sowing densities of the crop and the weed. The bean cultivar IPR Uirapuru was used. The treatments consisted of four bean densities (140,000; 180,000; 220,000 and 260,000 plants ha-1, respectively) and alexandergrass that varied from 0 to the maximum of 104 plants m-2. The experiment was installed in a Red Aluminoferric Latosol, at the experimental area of the Federal University of the Southern Border, campus Erechim/RS, on 10/31/2016. We used the rectangular hyperbola model to describe the relationship between the loss of bean grain yield and the explanatory variables of plant density (DP), soil cover (CS), leaf area (AF) and shoot dry matter (MS). Therefore, the variables CS and DP can be used instead of AF and MS to estimate grain yield losses in common beans. The density of 260,000 plants ha-1of bean showed greater competitiveness with alexandergrass and the highest values of EDLs, justifying the adoption of weed control management at higher densities.

O estudo da densidade de semeadura do feijoeiro e do nível de dano econômico (NDE) ocasionado pelo papuã (Urochloa plantaginea) são ferramentas importantes para a adoção do manejo integrado dessa planta daninha e, assim, produzir um alimento com maior qualidade e menor resíduo de agrotóxico. Diante disso, objetivou-se com o trabalho avaliar a interferência e o nível de dano econômico do papuã em competição com o feijoeiro, estimados em função de densidades de semeadura da cultura e da planta daninha. Os tratamentos foram compostos por densidades do feijoeiro, cultivar IPR Uirapuru (140.000, 180.000, 220.000 e 260.000 plantas ha-1) e do papuã que variaram de 0 até o máximo de 104 plantas m-2. O experimento foi implantado em um Latossolo Vermelho Aluminoférrico típico na área experimental da Universidade Federal da Fronteira Sul, campus Erechim/RS, em 31/10/2016. Para descrever a relação entre a perda de produtividade de grãos do feijoeiro e as variáveis explicativas; densidade de plantas (DP), cobertura do solo (CS), área foliar (AF) e massa seca da parte aérea (MS), usou-se o modelo da hipérbole retangular. As variáveis CS e DP podem ser usadas em substituição a AF e a MS para estimar as perdas de produtividades de grãos do feijoeiro. A densidade de 260.000 plantas ha-1do feijoeiro apresentou maior competitividade com o papuã e os maiores valores de NDEs, justificando aadoção de medidas de controle da planta daninha em densidades mais elevadas.

Effects of the Inclusion of Dietary Organic Acid Supplementation with Anti-Coccidium Vaccine on Growth Performance, Digestibility, Fecal Microbial, and Chicken Fecal Noxious Gas Emissions

A total of 792 conventional healthy 1-day-old Ross 308 broilers chicks (mixed gender) with average body weight of 42.30±1.14 g (mean ± SD) were used in the experiment, which lasted for 35 days. Chicks were randomly allotted into one of four treatment diets, each one having 11 replicate cages with 18 birds each, being fed corn-soybean meal (SBM) based diets. Dietary treatments were CON (basal diet with unvaccinated birds); OA = CON + 0.1% organic acids; ACB = CON + anti-coccidium vaccine; OAACV = CON + 0.1% organic acid + anti-coccidium vaccine. Significant results were observed, with improved body weight (p=0.059; 0.064; 0.034) during days 1-7, 8-21, and overall, respectively. Significant effects were also observed on the feed conversion ratio (p=0.037) through the overall experiment, with no effects on feed intake on OAACV as compared to other treatment groups. Total track digestibility of dry matter (p=0.049) improved significantly in the OAACV treatment group. Additionally, beneficial effects were observed in the OAACV treatment group, with improvements in fecal microbial population (increased lactobacillus) and reduced NH3 gas emissions. Broilers fed the OAACV treatment tended to display reduced drip loss in the meat samples analyzed on days 5 and 7 (p=0.067, 0.072). In summary, our findings revealed that dietary inclusion of organic acid supplementation with anti-coccidium had a beneficial effect on broilers affected by coccidian infection, also improving growth performance, digestibility, fecal Lactobacillus counts, and reducing NH3.(AU)

Effects of the Inclusion of Dietary Organic Acid Supplementation with Anti-Coccidium Vaccine on Growth Performance, Digestibility, Fecal Microbial, and Chicken Fecal Noxious Gas Emissions

A total of 792 conventional healthy 1-day-old Ross 308 broilers chicks (mixed gender) with average body weight of 42.30±1.14 g (mean ± SD) were used in the experiment, which lasted for 35 days. Chicks were randomly allotted into one of four treatment diets, each one having 11 replicate cages with 18 birds each, being fed corn-soybean meal (SBM) based diets. Dietary treatments were CON (basal diet with unvaccinated birds); OA = CON + 0.1% organic acids; ACB = CON + anti-coccidium vaccine; OAACV = CON + 0.1% organic acid + anti-coccidium vaccine. Significant results were observed, with improved body weight (p=0.059; 0.064; 0.034) during days 1-7, 8-21, and overall, respectively. Significant effects were also observed on the feed conversion ratio (p=0.037) through the overall experiment, with no effects on feed intake on OAACV as compared to other treatment groups. Total track digestibility of dry matter (p=0.049) improved significantly in the OAACV treatment group. Additionally, beneficial effects were observed in the OAACV treatment group, with improvements in fecal microbial population (increased lactobacillus) and reduced NH3 gas emissions. Broilers fed the OAACV treatment tended to display reduced drip loss in the meat samples analyzed on days 5 and 7 (p=0.067, 0.072). In summary, our findings revealed that dietary inclusion of organic acid supplementation with anti-coccidium had a beneficial effect on broilers affected by coccidian infection, also improving growth performance, digestibility, fecal Lactobacillus counts, and reducing NH3.

Competitive interaction and economic injury level of Urochloa plantaginea in corn hybrids / Interação competitiva e nível de dano econômico de papuã em híbridos de milho

Identifying the competitive ability of corn hybrids and the economic injury level (EIL) caused by Urochloa plantaginea is important for the adoption of integrated management of this weed. This work aims to evaluate the interference and EIL of U. plantaginea infesting corn hybrids. Treatments included the corn hybrids Syngenta Status VIP3, Syngenta SX8394 VIP3, Pioneer P1630H, Pioneer 30F53 YH, and Dow 135021, as well as 12 densities of U. plantaginea for each hybrid. We used a rectangular hyperbolic model to describe the relationship between corn grain productivity loss and the explanatory variables ­ plant density (PD), dry mass (DM) of the aerial parts, ground cover (GC), and leaf area (LA). EIL was determined using grain productivity, control cost, corn price, and herbicide efficacy. The rectangular hyperbolic model provides a satisfactory estimate of grain productivity loss regarding the interference of U. plantaginea in corn culture. The hybrids Pioneer 30F53 YH and Pioneer P1630H presented better competitiveness and higher EIL. Sowing the hybrids Pioneer P1630H, Pioneer 30F53 YH, and Dow 135021 increased EIL, justifying the adoption of control measures for U. plantaginea at higher densities.(AU)

A identificação da habilidade competitiva de híbridos de milho e do nível de dano econômico (NDE) ocasionado pelo papuã (Urochloa plantaginea) torna-se importante para a adoção do manejo integrado dessa planta daninha. Diante disso, objetivou-se com este trabalho avaliar a interferência e o NDE de papuã infestante de híbridos de milho. Os tratamentos foram compostos pelos híbridos de milho Syngenta Status VIP 3, Syngenta SX8394 VIP 3, Pioneer P1630H, Pioneer 30F53 YH e Dow 135021 e 12 densidades de plantas de papuã para cada híbrido. Para descrever a relação entre a perda de produtividade de grãos do milho e as variáveis explicativas densidade de plantas (DP), massa seca da parte aérea (MS), cobertura do solo (CS) e área foliar (AF), usou-se o modelo da hipérbole retangular. A determinação do NDE foi efetuada usando-se a produtividade de grãos, custo de controle, preço do milho e eficiência do herbicida. O modelo da hipérbole retangular estima de modo satisfatório as perdas de produtividade de grãos em função da interferência do papuã na cultura do milho. Os híbridos Pionner 30F53 YH e Pionner P1630H apresentaram melhor competitividade e os maiores NDEs. A semeadura dos híbridos Pioneer P1630H, Pioneer 30F53 YH e Dow 135021 aumenta o NDE, justificando a adoção de medidas de controle em densidades mais elevadas.(AU)

Competitive interaction and economic injury level of Urochloa plantaginea in corn hybrids / Interação competitiva e nível de dano econômico de papuã em híbridos de milho

Identifying the competitive ability of corn hybrids and the economic injury level (EIL) caused by Urochloa plantaginea is important for the adoption of integrated management of this weed. This work aims to evaluate the interference and EIL of U. plantaginea infesting corn hybrids. Treatments included the corn hybrids Syngenta Status VIP3, Syngenta SX8394 VIP3, Pioneer P1630H, Pioneer 30F53 YH, and Dow 135021, as well as 12 densities of U. plantaginea for each hybrid. We used a rectangular hyperbolic model to describe the relationship between corn grain productivity loss and the explanatory variables ­ plant density (PD), dry mass (DM) of the aerial parts, ground cover (GC), and leaf area (LA). EIL was determined using grain productivity, control cost, corn price, and herbicide efficacy. The rectangular hyperbolic model provides a satisfactory estimate of grain productivity loss regarding the interference of U. plantaginea in corn culture. The hybrids Pioneer 30F53 YH and Pioneer P1630H presented better competitiveness and higher EIL. Sowing the hybrids Pioneer P1630H, Pioneer 30F53 YH, and Dow 135021 increased EIL, justifying the adoption of control measures for U. plantaginea at higher densities.(AU)

A identificação da habilidade competitiva de híbridos de milho e do nível de dano econômico (NDE) ocasionado pelo papuã (Urochloa plantaginea) torna-se importante para a adoção do manejo integrado dessa planta daninha. Diante disso, objetivou-se com este trabalho avaliar a interferência e o NDE de papuã infestante de híbridos de milho. Os tratamentos foram compostos pelos híbridos de milho Syngenta Status VIP 3, Syngenta SX8394 VIP 3, Pioneer P1630H, Pioneer 30F53 YH e Dow 135021 e 12 densidades de plantas de papuã para cada híbrido. Para descrever a relação entre a perda de produtividade de grãos do milho e as variáveis explicativas densidade de plantas (DP), massa seca da parte aérea (MS), cobertura do solo (CS) e área foliar (AF), usou-se o modelo da hipérbole retangular. A determinação do NDE foi efetuada usando-se a produtividade de grãos, custo de controle, preço do milho e eficiência do herbicida. O modelo da hipérbole retangular estima de modo satisfatório as perdas de produtividade de grãos em função da interferência do papuã na cultura do milho. Os híbridos Pionner 30F53 YH e Pionner P1630H apresentaram melhor competitividade e os maiores NDEs. A semeadura dos híbridos Pioneer P1630H, Pioneer 30F53 YH e Dow 135021 aumenta o NDE, justificando a adoção de medidas de controle em densidades mais elevadas.(AU)

Comparison of gut microbial diversity in Beijing oil and Arbor Acres chickens

The Beijing oil (BJO) chicken is an autochthona Chinese breed which shows outstanding meat quality characteristics compared with fast-growing imported chickens such as Arbor Acres (AA) chickens. Gut microbial diversity has been shown to influence host factors such as energy and nutrient metabolism, immune response and fertility. Consequently, it is hoped that analyses into host microbial populations will ultimately help to improve the quality of associated meat products. Two distinct chicken breeds, Arbor Acres (AA) and Beijing oil (BJO), were selected to analyze the composition of the 16S rRNA gene V3-V5 hypervariable regions using high-throughput sequencing technology. Upon elucidation of gut-colonizing bacteria, the Firmicutes were observed to encompass the dominant phylum. The abundance of Firmicutes in the BJO chickens (84.9%) was lower than in the AA chickens (89.9%). Conversely, the prevalence of Proteobacteria was 4.8% in BJO chickens, with a significantly lower abundance observed in AA chickens (1.3%). In the cecum, the Firmicutes were once more the dominant phylum in BJO chickens (60.2%) and AA chickens (63.7%). The abundance of bacteroidetes was 37.7% in BJO chickens and 34.9% in AA chickens, respectively. These discoveries provide a perception into the composition of the gut microbiotain both breeds. The study also provides a foundation for future research relating to gut bacterial factors that may influence the development and progression of gastrointestinal disease in chickens and other animals.(AU)

Comparison of gut microbial diversity in Beijing oil and Arbor Acres chickens

The Beijing oil (BJO) chicken is an autochthona Chinese breed which shows outstanding meat quality characteristics compared with fast-growing imported chickens such as Arbor Acres (AA) chickens. Gut microbial diversity has been shown to influence host factors such as energy and nutrient metabolism, immune response and fertility. Consequently, it is hoped that analyses into host microbial populations will ultimately help to improve the quality of associated meat products. Two distinct chicken breeds, Arbor Acres (AA) and Beijing oil (BJO), were selected to analyze the composition of the 16S rRNA gene V3-V5 hypervariable regions using high-throughput sequencing technology. Upon elucidation of gut-colonizing bacteria, the Firmicutes were observed to encompass the dominant phylum. The abundance of Firmicutes in the BJO chickens (84.9%) was lower than in the AA chickens (89.9%). Conversely, the prevalence of Proteobacteria was 4.8% in BJO chickens, with a significantly lower abundance observed in AA chickens (1.3%). In the cecum, the Firmicutes were once more the dominant phylum in BJO chickens (60.2%) and AA chickens (63.7%). The abundance of bacteroidetes was 37.7% in BJO chickens and 34.9% in AA chickens, respectively. These discoveries provide a perception into the composition of the gut microbiotain both breeds. The study also provides a foundation for future research relating to gut bacterial factors that may influence the development and progression of gastrointestinal disease in chickens and other animals.

Arbuscular mycorrhizal fungi associated with the babassu palm (Attalea speciosa) in the eastern periphery of Amazonia, Brazil / Fungos micorrízicos arbusculares associados com a palmeira babaçu (Attalea speciosa) na periferia leste da Amazônia, Brasil

Babassu, Attalea speciosa (Arecaceae) is a ruderal palm native to Amazonia, which turned dominant in frequently burned lands throughout the arc of deforestation and other degraded lands, in extreme cases attaining complete dominance. This study investigated arbuscular mycorrhizal fungi (AMF) as one possible explanation for the outstanding ecological success of this exceptional palm. We explored the relationships between the babassu palm and native arbuscular mycorrhizal fungi and babassu effects on the AMF richness and mycorrhizal inoculum potential (MIP) in the eastern periphery of Amazonia. For this purpose, we sampled topsoil (0-20 cm) at the onset of the rainy season from a 5-year-old secondary forest regrowth (SEC) area with three levels of babassu dominance (sites with 10, 50 and 70% babassu biomass shares), and at three distances (0, 2.5 and 4 m) from isolated babassu patches within a degraded pasture (PAS), both with five replications per treatment. Glomerospore density varied from 100 to 302 per gram of soil, 56% higher in SEC than PAS. We identified a total of 16 AMF species, with dominance of Acaulospora (six species) followed by Glomus (three species). AMF richness increased with babassu dominance in SEC sites, and reduced with distance from babassu patches within the PAS. The colonization rate of babassu roots was higher in SEC than in PAS, whereas MIP was similar in both areas and without treatment differences. Our study points to strong mycorrhizal association of the babassu palm as a potential mechanism for its outstanding ecological success in degraded lands.

Babaçu, Attalea speciosa (Arecaceae) é uma palmeira ruderal nativa da Amazônia, dominante em terras frequentemente queimadas ao longo do arco de desmatamento e outras áreas degradadas, em casos extremos atingindo domínio completo. Este estudo investigou os fungos micorrízicos arbusculares (FMA) como possível explicação do sucesso ecológico desta palmeira. Nós exploramos as relações entre o babaçu e glomerosporos, efeitos do babaçu na riqueza destes fungos e o potencial do inóculo micorrízico (PIM) na periferia oriental da Amazônia. Amostras de solo (0-20 cm) foram coletadas no início da estação chuvosa em uma área de floresta secundária (SEC) de cinco anos de idade e três níveis de dominância do babaçu (10, 50 e 70% de biomassa de babaçu) e a três distâncias (0; 2,5 e 4 m) de ilhas de babaçu isoladas em uma pastagem degradada (PAS), ambas com cinco repetições por tratamento. A densidade de esporos de FMA variou de 100 a 302 por grama de solo, sendo 56% maior em SEC do que em PAS. Dezesseis espécies de FMA foram identificadas, com predominância de Acaulospora (seis espécies) seguidos do gênero Glomus (três espécies). A riqueza destes fungos aumentou com o domínio da palmeira em SEC e reduziu com a distância das ilhas de babaçu em PAS. A taxa de colonização das raízes de babaçu foi superior nas áreas de SEC enquanto o PIM não apresentou diferenças entre os tratamentos. Nosso estudo aponta a uma forte associação micorrhízica da palmeira babaçu, um possível mecanismo central no seu sucesso ecológico em áreas degradadas.

Arbuscular mycorrhizal fungi associated with the babassu palm (Attalea speciosa) in the eastern periphery of Amazonia, Brazil / Fungos micorrízicos arbusculares associados com a palmeira babaçu (Attalea speciosa) na periferia leste da Amazônia, Brasil

Babassu, Attalea speciosa (Arecaceae) is a ruderal palm native to Amazonia, which turned dominant in frequently burned lands throughout the arc of deforestation and other degraded lands, in extreme cases attaining complete dominance. This study investigated arbuscular mycorrhizal fungi (AMF) as one possible explanation for the outstanding ecological success of this exceptional palm. We explored the relationships between the babassu palm and native arbuscular mycorrhizal fungi and babassu effects on the AMF richness and mycorrhizal inoculum potential (MIP) in the eastern periphery of Amazonia. For this purpose, we sampled topsoil (0-20 cm) at the onset of the rainy season from a 5-year-old secondary forest regrowth (SEC) area with three levels of babassu dominance (sites with 10, 50 and 70% babassu biomass shares), and at three distances (0, 2.5 and 4 m) from isolated babassu patches within a degraded pasture (PAS), both with five replications per treatment. Glomerospore density varied from 100 to 302 per gram of soil, 56% higher in SEC than PAS. We identified a total of 16 AMF species, with dominance of Acaulospora (six species) followed by Glomus (three species). AMF richness increased with babassu dominance in SEC sites, and reduced with distance from babassu patches within the PAS. The colonization rate of babassu roots was higher in SEC than in PAS, whereas MIP was similar in both areas and without treatment differences. Our study points to strong mycorrhizal association of the babassu palm as a potential mechanism for its outstanding ecological success in degraded lands.(AU)

Babaçu, Attalea speciosa (Arecaceae) é uma palmeira ruderal nativa da Amazônia, dominante em terras frequentemente queimadas ao longo do arco de desmatamento e outras áreas degradadas, em casos extremos atingindo domínio completo. Este estudo investigou os fungos micorrízicos arbusculares (FMA) como possível explicação do sucesso ecológico desta palmeira. Nós exploramos as relações entre o babaçu e glomerosporos, efeitos do babaçu na riqueza destes fungos e o potencial do inóculo micorrízico (PIM) na periferia oriental da Amazônia. Amostras de solo (0-20 cm) foram coletadas no início da estação chuvosa em uma área de floresta secundária (SEC) de cinco anos de idade e três níveis de dominância do babaçu (10, 50 e 70% de biomassa de babaçu) e a três distâncias (0; 2,5 e 4 m) de ilhas de babaçu isoladas em uma pastagem degradada (PAS), ambas com cinco repetições por tratamento. A densidade de esporos de FMA variou de 100 a 302 por grama de solo, sendo 56% maior em SEC do que em PAS. Dezesseis espécies de FMA foram identificadas, com predominância de Acaulospora (seis espécies) seguidos do gênero Glomus (três espécies). A riqueza destes fungos aumentou com o domínio da palmeira em SEC e reduziu com a distância das ilhas de babaçu em PAS. A taxa de colonização das raízes de babaçu foi superior nas áreas de SEC enquanto o PIM não apresentou diferenças entre os tratamentos. Nosso estudo aponta a uma forte associação micorrhízica da palmeira babaçu, um possível mecanismo central no seu sucesso ecológico em áreas degradadas.(AU)

Temporal differences in breeding site use between tits and mice

Describing the interactions among cavity breeders is key to understanding their breeding ecology. In this study the temporal difference in cavity use between the great tit, Parus major (Linnaeus, 1758) and the small Japanese field mice, Apodemus argenteus (Temminck, 1845) is investigated, as a first step for clarifying the interaction between bird and mammal cavity breeders. Forty-seven nest boxes were installed on tree trunks in two urban forests of Hokkaido Island, Japan, and the breeding nests of tits and mice were found in 34 and 11 boxes, respectively. The tits used the nest boxes throughout the breeding season, from May to July. In contrast, mice breeding nests were found in the last half of the breeding season, from July to October. Our results showed that field mice rarely used boxes during the tits’ breeding season. This study provides important information, such as temporal differences in breeding site use between tits and mice.

Temporal differences in breeding site use between tits and mice

Describing the interactions among cavity breeders is key to understanding their breeding ecology. In this study the temporal difference in cavity use between the great tit, Parus major (Linnaeus, 1758) and the small Japanese field mice, Apodemus argenteus (Temminck, 1845) is investigated, as a first step for clarifying the interaction between bird and mammal cavity breeders. Forty-seven nest boxes were installed on tree trunks in two urban forests of Hokkaido Island, Japan, and the breeding nests of tits and mice were found in 34 and 11 boxes, respectively. The tits used the nest boxes throughout the breeding season, from May to July. In contrast, mice breeding nests were found in the last half of the breeding season, from July to October. Our results showed that field mice rarely used boxes during the tits breeding season. This study provides important information, such as temporal differences in breeding site use between tits and mice.(AU)

Agronomical performance of potato (Solanum tuberosum L.) cv. 'Unica' under inoculation with native rhizobacteria and application of acetyl salicylic acid / Desempenho agronômico da batata (Solanum tuberosum L.) cv. 'Unica' sob inoculação com rhizobacterias nativas e aplicação de ácido acetil salicílico

Peru is center of origin of potato and its wild relatives, so it is convenient to develop new technologies of agronomical management with less impact on the ecosystem, as in the use of pesticides and chemical fertilizers in potato is increasing in developing countries. The objective of the work was to evaluate the agronomic performance of potato cv. 'Unica' under inoculation with PGPR rhizobacteria isolated from the rhizosphere of Andean potatoes and on the effect of the application of acetylsalicylic acid in field conditions of the Peruvian coast. Inoculation of four bacterial isolates were evaluated: Bacillus simplex B13, Bacillus amyloliquefaciens Bac 15Mb, Azotobacter sp. Azo 16M2 and Pantoea sp. DZ22, as well as a dose of 0.4 mM acetyl salicylic acid as promoter treatments for plant growth versus a control with no inoculation. A randomized complete block design was used in a sandy loam class soil, slightly alkaline, with low organic content and free of salts. There was a relative humidity between 54 and 71%, while the average air temperatures ranged between 13 and 21 ºC in San Vicente de Cañete, Lima (coordinates UTM 18L3540788550372). Inoculated plants with bacterial strains at sowing time and control were evaluated at flowering in plots of 40 plants with three replications for several physiological and productive parameters. Means were separated statistically through Duncan's multiple range test and processed with Infostat software. Inoculation with strain Azotobacter sp. Azo 16M2, showed significant differences (p<0.05) with respect to control without inoculation, increasing tuber yield and commercial tuber weight per hectare and with less damage by the leafminer fly (Liriomyza huidobrensis) vis-à-vis the control. Also application of acetyl salicylic acid showed higher percentage of inflorescences (p<0.05) compared to the control, while statistical differences were not found between bacterial strains...

Peru é o centro de origem da batata e seus parentes silvestres, por isso é conveniente desenvolver novas tecnologias de gestão agronômica com menor impacto no ecossistema, como o uso de pesticidas e fertilizantes químicos em batata está aumentando nos países em desenvolvimento. O objetivo do trabalho foi avaliar o desempenho agronômico da cv. 'Unica' sob inoculação com rizobactérias PGPR isoladas da rizosfera de batata andina e pelo efeito da aplicação de ácido acetilsalicílico nas condições de campo da costa peruana. Avaliou-se a inoculação de quatro isolados bacterianos: Bacillus simplex B13, B. amyloliquefaciens Bac 15Mb, Azotobacter sp. Azo 16M2 e Pantoea sp. DZ22 bem como uma dose de 0,4 mM de ácido acetilsalicílico como promotores de tratamentos para o crescimento das plantas versus um controle sem inoculação. Utilizou-se um delineamento em blocos casualizados, em um solo franco-arenoso,  ligeiramente alcalino, de baixo conteúdo orgânico e livre de sais. O clima durante o ensaio apresentou uma umidade relativa entre 54 e 71%, temperaturas médias entre 13 e 21 ºC em San Vicente de Cañete, Lima (coordenadas UTM  18L3540788550372). As plantas foram inoculadas com estirpes bacterianas no momento da semeadura e na floração e os tratamentos foram avaliados em parcelas de 40 plantas com três repetições para diversos parâmetros fisiológicos e produtivos. Os dados foram analisados estatisticamente através do teste de Duncan e processados com o software Infostat. A inoculação com a estirpe Azo 16M2, apresentou diferenças significativas (p<0,05) em relação ao controle sem inoculação, aumentando a produção de tubérculos e o peso comercial de tubérculos por hectare e com menor dano pela mosca minadora (Liriomyza huidobrensis) em relação ao controle. Também a aplicação de ácido acetilsalicílico apresentou maior porcentagem de inflorescências (p<0,05) em relação ao controle, enquanto que diferenças estatísticas não foram encontradas entre...

Agronomical performance of potato (Solanum tuberosum L.) cv. 'Unica' under inoculation with native rhizobacteria and application of acetyl salicylic acid / Desempenho agronômico da batata (Solanum tuberosum L.) cv. 'Unica' sob inoculação com rhizobacterias nativas e aplicação de ácido acetil salicílico

Peru is center of origin of potato and its wild relatives, so it is convenient to develop new technologies of agronomical management with less impact on the ecosystem, as in the use of pesticides and chemical fertilizers in potato is increasing in developing countries. The objective of the work was to evaluate the agronomic performance of potato cv. 'Unica' under inoculation with PGPR rhizobacteria isolated from the rhizosphere of Andean potatoes and on the effect of the application of acetylsalicylic acid in field conditions of the Peruvian coast. Inoculation of four bacterial isolates were evaluated: Bacillus simplex B13, Bacillus amyloliquefaciens Bac 15Mb, Azotobacter sp. Azo 16M2 and Pantoea sp. DZ22, as well as a dose of 0.4 mM acetyl salicylic acid as promoter treatments for plant growth versus a control with no inoculation. A randomized complete block design was used in a sandy loam class soil, slightly alkaline, with low organic content and free of salts. There was a relative humidity between 54 and 71%, while the average air temperatures ranged between 13 and 21 ºC in San Vicente de Cañete, Lima (coordinates UTM 18L3540788550372). Inoculated plants with bacterial strains at sowing time and control were evaluated at flowering in plots of 40 plants with three replications for several physiological and productive parameters. Means were separated statistically through Duncan's multiple range test and processed with Infostat software. Inoculation with strain Azotobacter sp. Azo 16M2, showed significant differences (p<0.05) with respect to control without inoculation, increasing tuber yield and commercial tuber weight per hectare and with less damage by the leafminer fly (Liriomyza huidobrensis) vis-à-vis the control. Also application of acetyl salicylic acid showed higher percentage of inflorescences (p<0.05) compared to the control, while statistical differences were not found between bacterial strains...(AU)

Peru é o centro de origem da batata e seus parentes silvestres, por isso é conveniente desenvolver novas tecnologias de gestão agronômica com menor impacto no ecossistema, como o uso de pesticidas e fertilizantes químicos em batata está aumentando nos países em desenvolvimento. O objetivo do trabalho foi avaliar o desempenho agronômico da cv. 'Unica' sob inoculação com rizobactérias PGPR isoladas da rizosfera de batata andina e pelo efeito da aplicação de ácido acetilsalicílico nas condições de campo da costa peruana. Avaliou-se a inoculação de quatro isolados bacterianos: Bacillus simplex B13, B. amyloliquefaciens Bac 15Mb, Azotobacter sp. Azo 16M2 e Pantoea sp. DZ22 bem como uma dose de 0,4 mM de ácido acetilsalicílico como promotores de tratamentos para o crescimento das plantas versus um controle sem inoculação. Utilizou-se um delineamento em blocos casualizados, em um solo franco-arenoso,  ligeiramente alcalino, de baixo conteúdo orgânico e livre de sais. O clima durante o ensaio apresentou uma umidade relativa entre 54 e 71%, temperaturas médias entre 13 e 21 ºC em San Vicente de Cañete, Lima (coordenadas UTM  18L3540788550372). As plantas foram inoculadas com estirpes bacterianas no momento da semeadura e na floração e os tratamentos foram avaliados em parcelas de 40 plantas com três repetições para diversos parâmetros fisiológicos e produtivos. Os dados foram analisados estatisticamente através do teste de Duncan e processados com o software Infostat. A inoculação com a estirpe Azo 16M2, apresentou diferenças significativas (p<0,05) em relação ao controle sem inoculação, aumentando a produção de tubérculos e o peso comercial de tubérculos por hectare e com menor dano pela mosca minadora (Liriomyza huidobrensis) em relação ao controle. Também a aplicação de ácido acetilsalicílico apresentou maior porcentagem de inflorescências (p<0,05) em relação ao controle, enquanto que diferenças estatísticas não foram encontradas entre...(AU)

Microbial interactions: ecology in a molecular perspective

The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.(AU)

Current applications and different approaches for microbial L-asparaginase production

L-asparaginase (EC 3.5.1.1) is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL) and Hodgkin's lymphoma), and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc.) Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.(AU)

Microbial interactions: ecology in a molecular perspective

ABSTRACT The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.

The effects of introducing the Amazonian squirrel monkey on the behavior of the northeast marmoset / Efeitos da introdução do macaco-de-cheiro amazônico sobre o comportamento do sagui-do-nordeste

The squirrel monkey Saimiri sciureus, an endemic primate of the Amazonian Basin, has been introduced in many localities of the Atlantic Forest biome. Introduced exotic species gain a competitive advantage in their new environment because of a lack of natural predators, competitors or diseases. This advantage can result in a reduction in the resources for the endemic species. The aims of this work were to evaluate the level of adaptation, and monitor the forms of interaction and the impact caused by S. sciureus on the behavior of the native species Callithrix jacchus in the Saltinho Biological Reserve, Tamandaré, Pernambuco, Brazil. The behavior was assessed by use of scan sampling method, every 5 min. A total of 382 h (191 h or 2,292 scans per group) of time sampling was performed. Sixteen interactions were recorded. The interaction index was low and represented 2.4% of the total observation time. Interactions were significantly higher during the dry season (58.5%) relative to the rainy season (41.5%). Callithrix jacchus was intolerant to the presence of S. sciureus and the last one was more tolerant during the interactions. In the presence of S. sciureus, C. jacchus eating, foraging, resting, socializing, and self-grooming behaviors were reduced while alertness was increased. Territorial behavior showed no significant difference. In the presence of S. sciureus, on average, the group of marmosets assembled at a higher layer of the forest stratum. The results might indicate a negative effect of S. sciureus on the native species, C. jacchus.

O mico-de-cheiro, Saimiri sciureus, uma espécie endêmica da Bacia Amazônica, tem sido introduzido com sucesso em muitas localidades do bioma Mata Atlântica. Espécies exóticas introduzidas adquirem uma vantagem competitiva em seu novo ambiente por causa da ausência de seus predadores naturais, resultando em uma redução dos recursos alimentares para as espécies endêmicas. Nossos objetivos foram avaliar o nível de adaptação e monitorar as formas de interação e do impacto causado pelo S. sciureus sobre o comportamento da espécie nativa, Callithrix jacchus, na Reserva Biológica de Saltinho, Tamandaré, Pernambuco, Brasil. O comportamento foi estudado através do método de amotragem scan sampling a cada 5 minutos. Um esforço amostral de 382 h (191 h ou 2.292 scans por grupo) foi obtido. Dezesseis interações foram registradas. O índice de interação foi baixo e representou 2,4% to total de tempo de observação. As interações foram significantemente maiores na estação seca (58,5%) do que na estação chuvosa (41,5%). Em termos de tipos de interação, C. jacchus foi intolerante à presença de S. sciureus, que por sua vez apresentou alto nível de tolerância. Na presença de S. sciureus, o C. jacchus reduziu a alimentação, forrageamento, descanso, comportamentos sociais e autocatação e aumentou o comportamento de alerta. O comportamento territorial não apresentou diferença significante. Na presença do S. sciureus, no geral, o grupo de saguis permaneceu em um estrato mais alto na floresta. Os resultados parecem indicar um possível efeito negativo do S. sciureus sobre a espécie nativa, C. jacchus.

The effects of introducing the Amazonian squirrel monkey on the behavior of the northeast marmoset / Efeitos da introdução do macaco-de-cheiro amazônico sobre o comportamento do sagui-do-nordeste

The squirrel monkey Saimiri sciureus, an endemic primate of the Amazonian Basin, has been introduced in many localities of the Atlantic Forest biome. Introduced exotic species gain a competitive advantage in their new environment because of a lack of natural predators, competitors or diseases. This advantage can result in a reduction in the resources for the endemic species. The aims of this work were to evaluate the level of adaptation, and monitor the forms of interaction and the impact caused by S. sciureus on the behavior of the native species Callithrix jacchus in the Saltinho Biological Reserve, Tamandaré, Pernambuco, Brazil. The behavior was assessed by use of scan sampling method, every 5 min. A total of 382 h (191 h or 2,292 scans per group) of time sampling was performed. Sixteen interactions were recorded. The interaction index was low and represented 2.4% of the total observation time. Interactions were significantly higher during the dry season (58.5%) relative to the rainy season (41.5%). Callithrix jacchus was intolerant to the presence of S. sciureus and the last one was more tolerant during the interactions. In the presence of S. sciureus, C. jacchus eating, foraging, resting, socializing, and self-grooming behaviors were reduced while alertness was increased. Territorial behavior showed no significant difference. In the presence of S. sciureus, on average, the group of marmosets assembled at a higher layer of the forest stratum. The results might indicate a negative effect of S. sciureus on the native species, C. jacchus.(AU)

O mico-de-cheiro, Saimiri sciureus, uma espécie endêmica da Bacia Amazônica, tem sido introduzido com sucesso em muitas localidades do bioma Mata Atlântica. Espécies exóticas introduzidas adquirem uma vantagem competitiva em seu novo ambiente por causa da ausência de seus predadores naturais, resultando em uma redução dos recursos alimentares para as espécies endêmicas. Nossos objetivos foram avaliar o nível de adaptação e monitorar as formas de interação e do impacto causado pelo S. sciureus sobre o comportamento da espécie nativa, Callithrix jacchus, na Reserva Biológica de Saltinho, Tamandaré, Pernambuco, Brasil. O comportamento foi estudado através do método de amotragem scan sampling a cada 5 minutos. Um esforço amostral de 382 h (191 h ou 2.292 scans por grupo) foi obtido. Dezesseis interações foram registradas. O índice de interação foi baixo e representou 2,4% to total de tempo de observação. As interações foram significantemente maiores na estação seca (58,5%) do que na estação chuvosa (41,5%). Em termos de tipos de interação, C. jacchus foi intolerante à presença de S. sciureus, que por sua vez apresentou alto nível de tolerância. Na presença de S. sciureus, o C. jacchus reduziu a alimentação, forrageamento, descanso, comportamentos sociais e autocatação e aumentou o comportamento de alerta. O comportamento territorial não apresentou diferença significante. Na presença do S. sciureus, no geral, o grupo de saguis permaneceu em um estrato mais alto na floresta. Os resultados parecem indicar um possível efeito negativo do S. sciureus sobre a espécie nativa, C. jacchus.(AU)