Phenotypic and molecular characteristics of rhizobia isolated from nodules of peanut (Arachis hypogaea L.) grown in Brazilian Spodosols

Peanut (Arachis hypogaea L.) is an important crop that can fix nitrogen through symbiosis with rhizobia. Rhizobia populations with diverse characteristics than those traditionally described as peanut microsymbionts have been found in tropical soils. With the objective of studying the diversity and phylogeny of these rhizobia, 22 bacterial strains were isolated from nodules of seven peanut varieties grown in Spodosols of Pernambuco State, Brazil. The isolates were examined in culture medium by means of some of their phenotypic characteristics and tested for intrinsic antibiotic resistance (IAR). DNA profiles were determined with the BOX-PCR and compared with 19 reference strains. All isolates showed rapid growth, and most of them acidified the culture medium. In general, high antibiotic resistance was observed to penicillin G, chloramphenicol and tetracycline and susceptibility was observed to neomycin, erythromycin and rifampicin. The analysis of their phenotypic characteristics, that is, colony morphology and IAR, provided little information about the phylogeny of the isolates. However, using compilation of phenotypic and molecular characteristics, we were able to observe a great diversity of these rhizobia and to reveal the presence of new species.Keywords: Antibiotic resistance, Arachis hypogaea L., BOX-PCR, colony morphology, diversityAfrican Journal of Biotechnology Vol. 12(17), pp. 2147-215

Biofertilizantes com fosfato natural, enxofre e Acidithiobacillus em solo com baixo P disponível

A produção de biofertilizantes é um processo prático e econômico que reduz o consumo de energia e a sua aplicação visa aumentar o fósforo (P) disponível no solo. Biofertilizantes fosfatados (B5, B10, B15, B20) produzidos em laboratório usando fosfato natural (FN) e enxofre em diferentes concentrações (5; 10; 15 e 20%), inoculado com Acidithiobacillus (S*) e enxofre (20%) sem Acidithiobacillus (S), com incubação por 30, 45 e 60 dias, foi utilizado em um experimento em vasos com solo da Zona da Mata de Pernambuco (Argissolo Amarelo), com baixo nível de P disponível, cultivado com jacatupé (Pachyrhizus erosus), por dois períodos consecutivos. Os tratamentos fosfatados foram: fosfato natural (FN); biofertilizantes (B5, B10, B15, B20), com Acidithiobacillus (FN+S*) e B20, sem Acidithiobacillus (FN+S); superfosfato triplo (ST); e um controle sem fósforo (P0). As plantas foram inoculadas com a mistura das estirpes de rizóbio NFB 747 e 748, e sem inoculação. Nos ensaios em laboratório analisou-se o pH e o P extraído dos biofertilizantes, em cada período de incubação, e nos experimentos em vasos com solo determinou-se a biomassa seca, o N e o P total acumulado da parte aérea, o pH e o P extraído do solo. O P disponível foi mais elevado para os biofertilizantes com Acidithiobacillus (FN+S*) e para o superfosfato triplo. A fertilização fosfatada, condicionou resposta positiva dos biofertilizantes (FN+S*) e do superfosfato triplo. Os rizóbios nativos foram tão eficientes quanto os do inoculante. Após os dois cultivos o P disponível foi maior com os biofertilizantes B15 e B20 com Acidithiobacillus.The production of mineral fertilizers is a expensive process, since it requires high energy consumption, and cannot be produced by small farmers. Laboratory assays were conducted to produce P-biofertilizers from natural phosphate (B5, B10, B15, B20), applying sulphur at different rates (5; 10; 15 and 20%) inoculated with Acidithiobacillus (S*) and testing increasing periods of incubation. A greenhouse experiment was carried out to evaluate the effect of the biofertilizers in a soil with low available P (Typic Fragiudult) from the "Zona da Mata" of Pernambuco State, grown with yam bean (Pachyrhizus erosus) in two consecutive harvests. The treatments were: Natural Phosphate (NP); biofertilizers produced in laboratory (B5, B10, B15, B20) with sulphur and Acidithiobacillus (NP+S*); natural phosphate with sulphur (20%) without Acidithiobacillus (NP+S); triple super phosphate (TSP) and a control without phosphorus. Plants were inoculated with a mixture of rhizobia strains (NFB 747 and NFB 748) or did not receive rhizobia inoculation. In bioassays pH and available P in the biofertilizers were analyzed. In the greenhouse experiment shoot dry matter, total N and total P in shoots, soil pH and available P were determined. Higher rates of available P were obtained in biofertilizers with sulphur and Acidithiobacillus (NP+S*) and in triple super phosphate (TSP), and biofertilizers with sulphur and Acidithiobacillus (FN+S*) and triple super phosphate (TSP) increased plant parameters. Native rhizobia were as effective as the strains applied in inoculation. After the two harvests soil presented lower pH values and higher rates of available P when the biofertilizers B15 and B20 with sulphur and Acidithiobacillus were applied

Diversity of plant growth-promoting bacteria associated with sugarcane

The sugarcane (Saccharum spp) presents economic importance, mainly for tropical regions, being an important Brazilian commodity. However, this crop is strongly dependent on fertilizers, mainly nitrogen (N). This study assessed the plant growth-promoting bacteria (PGPB) associated with sugarcane that could be used as a potential inoculant to the crop. We evaluated the genetic diversity of PGPB in the plant tissue of sugarcane varieties (RB 867515, RB 1011, and RB 92579). The primer BOX-A1R was used to differentiate the similar isolated and further sequencing 16S rRNA ribosomal gene. The 16S rRNA gene showed the presence of seven different genera distributed into four groups, the genus Bacillus, followed by Paenibacillus (20%), Burkholderia (14%), Herbaspirillum (6%), Pseudomonas (6%), Methylobacterium (6%), and Brevibacillus (3%). The molecular characterization of endophytic isolates from sugarcane revealed a diversity of bacteria colonizing this plant, with a possible biotechnological potential to be used as inoculant and biofertilizers

Isolation and Characterization of Plant Growth-Promotion Diazotrophic Endophytic Bacteria Associated to Sugarcane (Saccharum officinarum L.) Grown in Paraíba, Brazil

Sugarcane is an important Brazilian commodity, being usually cultivated in soils with low natural fertility. This study aimed to isolate diazotrophic endophytes from sugarcane tissues and evaluate the morphological and physiological characteristics of their colonies as well as their plant growth-promoting (PGP) traits in select diazotrophic endophytic bacteria. Fifty-six bacterial isolates were identified in the sugarcane tissues, and these isolates presented distinct morphological and physiological traits. A total of thirty-five bacterial isolates were biochemically evaluated. Overall, Bacillus was the dominant genus. Isolates of Methylobacterium spp. and Brevibacillus agri were present only in leaves, while Herbaspirillum seropedicae occurred only in stems. Except to IPA-CF45A, all isolates were nitrogenase positive. All endophytes exhibit production of indol 3-acetic acid. Over 50% of endophytes solubilize phosphate, release N-acyl homoserine lactones, and present the activity of 1-aminocyclopropane-1-carboxylic acid deaminase, catalase, lipase and protease. The network analysis showed that isolates belonged to Burkholderia, Herbaspirillum, and Methylobacterium interact with Bacillus. Bacterial endophytes exhibited distinct morphological, physiological, and PGP traits that are useful for sustainable agriculture, highlighting the isolates IPA-CC33, IPA-CF65, IPA-CC9 and IPA-CF27. Further studies on the effects of these diazotrophic endophytes and their potential for providing microbial inoculants for improving sugarcane fields will provide valuable information to maintain the sustainability and environment quality.National Council for Scientific and Technological Development 426655/2018-

Rock biofertilizer and earthworm compost on sugarcane performance and soil attributes in two consecutive years

ABSTRACT The deployment of soluble fertilizers has been one of the most commonly applied agricultural practices in the bid to increase crop yield. However, the production of soluble fertilizers has a considerable economic cost and consumes a substantial amount of energy. In general, soil organic matter provides the nutrients needed for plant growth in organic agriculture. However, these nutrients are not sufficient if the best yield is to be obtained. The aim of our field experiment was to evaluate the effectiveness of phosphate and potassic sources (rocks, bio-fertilizers and soluble fertilizers) based on several sugarcane characteristics and soil attributes. Our experiment was conducted over two consecutive years, and we assessed the effect of using sugarcane filter mud cake (SFMC). In addition, we mixed the phosphate and potassic sources with earthworm compost enriched in N by inoculation with diazotrophic bacteria (OM) and applied at 50, 100 and 150 % of the recommended dosage rate (RDR). The PK biofertilizer with OM enriched in N positively affected sugarcane height, yield, and industrial characteristics. The application of SFMC greatly increased available P and K in the soil and plant characteristics with residual effect in the two consecutive harvests. We conclude that the biofertilizer has the potential to increase sugarcane characteristics and may represent an alternative to soluble fertilizers

Global, regional, and national incidence, prevalence, and years lived with disability for 354 diseases and injuries for 195 countries and territories, 1990–2017: A systematic analysis for the Global Burden of Disease Study 2017

Background: The Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017) includes a comprehensive assessment of incidence, prevalence, and years lived with disability (YLDs) for 354 causes in 195 countries and territories from 1990 to 2017. Previous GBD studies have shown how the decline of mortality rates from 1990 to 2016 has led to an increase in life expectancy, an ageing global population, and an expansion of the non-fatal burden of disease and injury. These studies have also shown how a substantial portion of the world's population experiences non-fatal health loss with considerable heterogeneity among different causes, locations, ages, and sexes. Ongoing objectives of the GBD study include increasing the level of estimation detail, improving analytical strategies, and increasing the amount of high-quality data. Methods: We estimated incidence and prevalence for 354 diseases and injuries and 3484 sequelae. We used an updated and extensive body of literature studies, survey data, surveillance data, inpatient admission records, outpatient visit records, and health insurance claims, and additionally used results from cause of death models to inform estimates using a total of 68 781 data sources. Newly available clinical data from India, Iran, Japan, Jordan, Nepal, China, Brazil, Norway, and Italy were incorporated, as well as updated claims data from the USA and new claims data from Taiwan (province of China) and Singapore. We used DisMod-MR 2.1, a Bayesian meta-regression tool, as the main method of estimation, ensuring consistency between rates of incidence, prevalence, remission, and cause of death for each condition. YLDs were estimated as the product of a prevalence estimate and a disability weight for health states of each mutually exclusive sequela, adjusted for comorbidity. We updated the Socio-demographic Index (SDI), a summary development indicator of income per capita, years of schooling, and total fertility rate. Additionally, we calculated differences between male and female YLDs to identify divergent trends across sexes. GBD 2017 complies with the Guidelines for Accurate and Transparent Health Estimates Reporting. Findings: Globally, for females, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and haemoglobinopathies and haemolytic anaemias in both 1990 and 2017. For males, the causes with the greatest age-standardised prevalence were oral disorders, headache disorders, and tuberculosis including latent tuberculosis infection in both 1990 and 2017. In terms of YLDs, low back pain, headache disorders, and dietary iron deficiency were the leading Level 3 causes of YLD counts in 1990, whereas low back pain, headache disorders, and depressive disorders were the leading causes in 2017 for both sexes combined. All-cause age-standardised YLD rates decreased by 3·9% (95% uncertainty interval [UI] 3·1-4·6) from 1990 to 2017; however, the all-age YLD rate increased by 7·2% (6·0-8·4) while the total sum of global YLDs increased from 562 million (421-723) to 853 million (642-1100). The increases for males and females were similar, with increases in all-age YLD rates of 7·9% (6·6-9·2) for males and 6·5% (5·4-7·7) for females. We found significant differences between males and females in terms of age-standardised prevalence estimates for multiple causes. The causes with the greatest relative differences between sexes in 2017 included substance use disorders (3018 cases [95% UI 2782-3252] per 100 000 in males vs 1400 [1279-1524] per 100 000 in females), transport injuries (3322 [3082-3583] vs 2336 [2154-2535]), and self-harm and interpersonal violence (3265 [2943-3630] vs 5643 [5057-6302]). Interpretation: Global all-cause age-standardised YLD rates have improved only slightly over a period spanning nearly three decades. However, the magnitude of the non-fatal disease burden has expanded globally, with increasing numbers of people who have a wide spectrum of conditions. A subset of conditions has remained globally pervasive since 1990, whereas other conditions have displayed more dynamic trends, with different ages, sexes, and geographies across the globe experiencing varying burdens and trends of health loss. This study emphasises how global improvements in premature mortality for select conditions have led to older populations with complex and potentially expensive diseases, yet also highlights global achievements in certain domains of disease and injury