Inoculation Of Diazotrophic Bacteria Research Articles

Proline Content, Physiological and Agronomic Characters of Rice (Oryza sativa cv. Inpari Unsoed 79 Agritan) under Treated with PGPR in Saline Medium

Tidal areas near the coastline are prone to salinity impacts as a negative impact of seawater intrusion which causes dissolved salt levels to increase. The biological approach using PGPR is an environmentally friendly approach. The aim of the study was to examine the effectiveness of useful bacteria from saline soils to increase the resistance of rice plants to salinity stress. The research was carried out from April to October 2022 in the Lab. Agronomy & Horticulture Faperta UNSOED. This research was experimental research using liquid culture techniques for cultivating plants using AB Mix media. The design used was a randomized block design with three replications. The treatments were included Control (P0), Acinetobacter junii (P1), Bacillus tropicus (P2), Acinetobacter schindleri (P3), Pseudomonas stutzeri (P4), Bacillus altitudinis (P5), Bacillus cereus (P6), dan Bacillus subtilis (P7). The results of the study showed that Diazotrophic Bacteria inoculation can increase the resistance of rice plants to rice plants by increasing proline production, increasing net assimilation rates and relative growth rates. Acinetobacter schindleri, Bacillus subtilis and Bacillus tropicus are potential N2 fixing bacterial strains to increase the growth and yield of rice under saline conditions. Treatment of Acinetobacter schindleri was able to provide the highest grain yields reaching 16.95 g/plant.

Diazotrophic bacteria and substrates in the growth and nitrogen accumulation of sugarcane seedlings

Little is known about the interaction between the inoculation of diazotrophic bacteria, the variety, and the substrate used in inoculated sugarcane seedling production. Bearing this in mind, the aim of this study was to evaluate the effects of diazotrophic bacteria inoculation, four sugarcane varieties and four different substrates on the growth and nitrogen accumulation of sugarcane seedlings. Parameters related to sprouting, height, and root growth, as well as nitrogen accumulation, were evaluated. The results indicate that inoculating sugarcane seedlings belonging to the following varieties: RB867515, RB92579, RB966928 and RB975932 with bacteria may increase sprouting speed index, height, root length, fresh and dry matter weight, as well as nitrogen accumulation, which has resulted in a more uniform stem diameter. However, the responses to inoculation differ from variety to variety and are also dependent on the substrate used with better results observed in the commercial substrate and the substrate mixtures containing a higher proportion of organic compost. Understanding the interaction between the variety and the substrate with the bacterial inoculation is essential to the success of the production of inoculated sugarcane seedlings.

Adoção de biotecnologias para revegetação mais eficiente por feijão-de-porco e crotalária em rejeito de minério de ferro

Often unable to regenerate naturally, areas degraded by ore tailings must follow measures aimed at their environmental recovery. The revegetation and the use of bio-stimulants can contribute to the improvement of soil fertility leading to increased production of plant biomass and the cycling of nutrients between soil-plant.The objective was to evaluate the dry matter production, accumulation and nutrient export rates by pig beanplants (Canavalia ensiformis) and Crotalaria juncea cv. IAC-KR-1 as a function of the application of humic substances and diazotrophic bacteria. The experiment was conducted in a greenhouseusing iron ore tailings as substrate. An experimental design of random blocks (4x3x2) was used with four repetitions, four doses of humic substances, applied at 3 different times, with or without inoculation of diazotrophic bacteria. The supply of humic substances and mainly the inoculation in both species increased the dry matter production, reaching 70% of the average increase in pig beans. Inoculation in pig bean plants increased the absorption and transfer factor of Fe and P, and reduced the transfer factor of K, Ca and Mg, and in crotalaria plants increased the absorption of Mg, P and Mn, and reduced the absorption of Fe. The high content of Fe in mining tailings culminated in high absorption and mobilization of this element in the roots of the plants as an alternative to minimize toxic effects caused by its excess.

Both the contribution of soil nitrogen and of biological N2 fixation to sugarcane can increase with the inoculation of diazotrophic bacteria

This study was performed to determine if the contribution of biological N2 fixation (BNF) associated with Brazilian sugarcane cultivars could be increased by the inoculation with N2-fixing bacteria. The field experiment was planted with two sugarcane cultivars, inoculated or not, with five N2-fixing bacteria. All plant tissues, including belowground, were harvested for determination of dry matter, N accumulation and 15N abundance at five occasions until 450 days after planting. Inoculation significantly increased total N accumulation in the aerial tissue of cultivar RB867515 from 147 to 199 kg N ha−1 and cultivar RB92579 from 126 to 192 N kg ha−1. At final harvest 15N abundances of entire sugarcane plants compared to that of plant-available N indicated that BNF inputs were over 64%. Total N derived from BNF and the soil was increased by inoculation, by 50 and 17 kg N ha−1 and 36 and 67 kg N ha−1, for the two cultivars respectively. Without inoculation, the two sugarcane cultivars obtained over 65% of N from BNF. Inoculation with the five component inoculant increased N accumulation from soil and BNF but with little impact on the proportion of N derived from BNF.

Inoculation of diazotrophic bacteria in chicory

ABSTRACT Inoculating crops with diazotrophic bacteria constitutes a feasible biotechnological tool to reduce or even avoid the use of nitrogen fertilizers and to improve the nutritional status of crops. However, the potential use of such technology is limited due to the lack of studies in diverse vegetable crops. We evaluated the production of chicory (Cichorium intybus) in response to inoculation with diazotrophic bacteria in two soil classes. The experiments were performed under greenhouse conditions and under a completely randomized design. The treatments were constituted by strains UFRB FA34C2-2, UFLA 03-84 and INPA 0311B, and two control treatments (devoid of bacterial inoculation and with and without nitrogen fertilization). Two experiments were carried out, one using a soil classified as a dystrophic yellow Latosol (Oxisoil) and one using a Quartsandy Neosol (Typic Quartzipsamment). Chlorophylls a, b and total; plant height; number of leaves; dry mass of the aerial portion; dry mass of roots; total dry mass; effectiveness; efficiency in addition to N and P gathering in the aerial portion, were evaluated 60 days after seeding. The inoculation with diazotrophic bacteria resulted in adequate production when compared to the control treatment without nitrogen fertilization and without inoculation. Diazotrophic bacteria showed potential supplying nitrogen to chicory plants and spare the use of nitrogen fertilization in both soil classes. The strain INPA 0311B, recommended for cowpea, promoted vegetal growth and increased the dry weight of the aerial portion in chicory, under both dystrophic yellow Latosol (Oxisoil) and Neossolo Quartzarênico (Typic Quartzipsamment), when cultivated under greenhouse conditions.

Effect of inoculant with technologies integrated in initial soybean growth

Soybeans are one of the most produced grains in the world, and because of the high cost of nitrogen fertilizers, new technologies in the inoculation of diazotrophic bacteria have been developed. The objective of this study was to evaluate the effect of Bradyrhizobium-based inoculant doses and Lipo-chito-oligosaccharide molecules (LCOs), together with bacterial protector as an additive, compared to a conventional inoculant in the inoculation of soybean seeds. The experiment was carried out in a greenhouse, with soil from a Red Oxissol of sandy texture. The experimental design was in randomized blocks with 3 replicates, the treatments being distributed in a 5 x 2 factorial scheme (2 inoculants and 5 inoculant doses). The seeds of the soybean cultivar M8866 were inoculated and seeded in the pots containing 11 L of substrate, where two plants remained for 45 days. Nine biometric-productive parameters were evaluated. Increasing the dose, regardless of the inoculant, provided an increase in root length and probably active nodules. In general, it was possible to observe statistical superiority of the inoculant with technologies integrated in relation to the conventional one, independent of the dose, when comparing the inoculants with respect to these two variables. Furthermore, the inoculant with integrated technologies provided a higher mass of fresh and dry matter of the nodules with the application of the highest inoculant dose (3.6 billion UFC mL-1). It was noted that increasing the dose of conventional inoculant did not cause the increase of fresh and dry matter mass of the nodules such as the inoculant with integrated technologies, suggesting the beneficial action of the bioprotectant and of the LCOs molecules.

Efficient inoculation of diazotrophic bacteria into sugarcane by the drip irrigation system

Abstract: The objective of this work was to assess the efficiency of the inoculation of a diazotrophic bacterial consortium by the drip irrigation system into sugarcane (Saccharum spp.), in the Brazilian semiarid region. The evaluated treatments were: standard inoculation by submersion; one or two inoculations by drip irrigation; nitrogen (urea) applied by fertigation; and negative controls, without inoculation or nitrogen fertilization. Leaf gas exchanges and plant growth and yield were assessed. Inoculation by irrigation is efficient for all variables, and double inoculation by the drip irrigation system stands out, increasing stem yield in 16% when compared with the negative control, without differing from the treatment with nitrogen fertilizer.

Nitrogen source contribution in sugarcane-inoculated plants with diazotrophic bacterias under urea-N fertigation management

Although Brazilian sugarcane crops use lower nitrogen rates when compared to other producing countries, the biological nitrogen fixation (BFN) could be performed aiming to reduce costs, since almost all nitrogen fertilization used in Brazil is imported. BFN can occur in sugarcane; however, its role in non-leguminous plants is controversial. Therefore, this study aimed to assess the nitrogen source contribution (using N isotope 15N technique) along a growing period in sugarcane plants under different management (diazotrophic bacteria inoculation and N fertigation rates). The natural abundance of nitrogen isotope (15N) abundance in + 1 leaves of fourth ratoon cultivar SP 80-3280 was used to indicate the comparative importance of N sources, including BFN for sugarcane nutrition. The treatments were irrigated with two levels of nitrogen fertilizer 50 and 100 kg ha−1 (urea source), including a control without fertilizer, with (I) and without (NI) inoculation of nitrogen-fixing bacterias. The bacteria cocktail used consisted of five strains: Gluconacetobacter diazotrophicus, Herbaspirillum seropedicae, H. rubrisubalbicans, Burkholderia tropica and Azospirillum amazonense. Although the nitrogen content in + 1 leaves, the above ground dry matter, cane yield and stalk sugar content expanded by increasing nitrogen fertilizer rates, no significant interactions between nitrogen-fixing bacteria inoculation and nitrogen fertilizer rates were observed. In the treatment without N fertilizer application, no differences in δ15N‰ (per thousand) values between sugarcane-inoculated and sugarcane-non-inoculated sugarcane leaves was found. The temporal variation of δ15N‰ in sugarcane + 1 leaves indicated that nitrogen content and δ15N‰ values decreased during the phenological development stages and that the main sources of nitrogen for sugarcane were from synthetic fertilizer and mineralization of nitrogen from soil organic matter.

Response of two wheat cultivars to inoculation of diazotrophic bacteria in combination with reduced nitrogen fertilisation under field conditions

Chemical fertilisers are essential for plant nutrition in attaining desired yields. However, increased cost of fertiliser input has made it impossible for small-scale farmers to properly fertilise their crops for optimum yields. Five bacterial strains originally isolated from no-till agricultural soil were tested as seed treatments for their potential to increase growth and yield of two wheat cultivars, under a low dose of nitrogen fertilisation in repeated split-plot field experiments. Two nitrogen levels (0% and 35%) with and without bacteria treatments were tested. The controls were 100% nitrogen, 0% nitrogen (uninoculated control) and 35% nitrogen control. Wheat yields were 51–96.5% higher than the uninoculated control and 24.7–43.1% higher than the fully fertilised control. Increases in shoot dry biomass were consistent with yield increases and varied with bacterial strain, cultivar used and growing season. All of the bacterial strains tested positive for ethylene, siderophore and indoleacetic acid (IAA) production. Ethylene and IAA production ranged from 28.4 to 51.3 nmol L−1 h−1, and from 2.1 to 14.6 mg mL−1, respectively. The consistency in yield response of wheat to bacterisation in the presence of a low dose of nitrogenous fertiliser indicates that these diazotrophs could be used as a supplement to nitrogenous fertiliser.

Produtividade e diluição isotópica de 15N em cana-de-açúcar inoculada com bactérias diazotróficas

Resumo O objetivo deste trabalho foi avaliar a produtividade e a diluição do isótopo 15N de duas variedades de cana-de-açúcar, inoculadas ou não com bactérias diazotróficas. Dois experimentos foram realizados nas regiões Sudeste e Nordeste do Brasil, durante três safras (2007/2008, 2008/2009 e 2009/2010): o primeiro em Argissolo Vermelho eutrófico, de textura argilosa, e o segundo em Planossolo Háplico distrófico, de textura média. Utilizou-se o delineamento de blocos ao acaso, com quatro repetições. As variedades testadas foram a RB867515 e a RB72454, cultivadas com inoculação com bactérias diazotróficas (cinco estirpes combinadas no inoculante para cana-de-açúcar) ou com adubação de 120 kg ha-1 de N, além do controle experimental sem inoculação e sem adubação. Avaliaram-se a produtividade de colmos e a diluição isotópica de 15N nas folhas-bandeira. A variedade RB72454 foi mais responsiva aos tratamentos, nos ciclos de cana-planta e na segunda soca. A abundância natural de 15N nas folhas-bandeira diminui ao longo dos anos, o que indica aumento da fixação biológica de N na medida em que a disponibilidade de N do solo vem sendo reduzida.

Adição de molibdênio ao inoculante turfoso com bactérias diazotróficas usado em duas cultivares de arroz irrigado

O objetivo deste trabalho foi avaliar o efeito da utilização de bactérias diazotróficas com ou sem molibdênio em duas cultivares de arroz com diferentes potenciais de fixação biológica de nitrogênio. Dois experimentos foram montados: o primeiro foi conduzido em condições gnotobióticas, com utilização das estirpes BR 11417 (ZAE94 - Herbaspirillum seropedicae) e BR 11340 (M130 - Burkholderia sp.), duas doses de molibdênio, 1,12 e 2,25 g, e duas fontes, molibdato de sódio e molibdato de amônio. As sementes foram peletizadas com inoculante turfoso com bactérias diazotróficas e o molibdênio. Em seguida as cultivares foram plantadas em tubos de ensaio com capacidade para 120 mL com 60 mL da solução de Hoagland sem nitrogênio por 30 dias. Foi avaliada a matéria seca das plantas. O segundo experimento foi conduzido em vasos em casa de vegetação, com as mesmas estirpes e dosagens de molibdênio. Foram avaliados a produção e o N total dos grãos. O delineamento estatístico foi inteiramente casualizado com quatro repetições e quatro plantas por vaso. Foram observados aumentos na produção de grãos nas cultivares IR42 e IAC4440 de 88 e 57%, respectivamente, com a adição ao inoculante turfoso, das estirpes ZAE94 e M130 com molibdênio.

Reinoculação de bactérias diazotróficas aumentando o crescimento de plantas de trigo

O presente estudo teve por objetivo avaliar o suprimento de N via FBN e a capacidade de isolados de bactérias diazotróficas, reinoculados em plantas de trigo, em promover o aumento do comprimento radicular. Foi feito um estudo sob condições controladas no qual avaliou a fixação biológica de nitrogênio e o aumento no comprimento radicular de plantas de trigo inoculadas com bactérias diazotróficas. Destacaram-se dois isolados testados pelo aumento de 2,3 vezes no comprimento radicular comparado aos tratamentos sem inoculação. Todos os isolados inoculados supriram a necessidade de N das plantas de trigo até os 21 dias de desenvolvimento. Por meio desta técnica foi possível identificar isolados promissores para inoculação em plantas de trigo.