Biofertilizer Inoculation Research Articles

Las rizobacterias halófilas mantienen la calidad forrajera de Moringa oleifera cultivada en sustrato salino

Para obtener un incremento en la producción forrajera de Moringa oleifera Lam. y de buena calidad se puede combinar el uso de compost a base de estiércol bovino y la inoculación de biofertilizantes a base de rizobacterias promotores del crecimiento vegetal (PGPR). La evaluación de esta producción se realizó en invernadero en Torreón, Coahuila, México. Se utilizó compost de estiércol bovino como sustrato (compost 50%, arena 40% y perlita 10%). Se programaron tres inoculaciones al árbol (a los 40, 74 y 152 días después de la siembra) con cuatro cepas de PGPR, los siguientes fueron los tratamientos T1: Bacillus paralicheniformis, T2: Acinetobacter guillouiae, T3: Aeromonas caviae, T4: Pseudomonas lini y Testigo: Sin bacteria, las cepas provenientes de la Poza Salada, Valle de Sobaco, Coahuila, México. Se realizaron tres cosechas en el ciclo verano-otoño-invierno 2016-2017. Se evaluaron variables agronómicas y bromatológicas para determinar la producción y calidad del follaje del árbol. Las cepas Pseudomonas lini y Bacillus paralicheniformis proporcionaron una respuesta positiva en el desarrollo de M. oleifera forrajera en el período de verano-otoño, incrementando la altura en las primeras semanas de desarrollo y proporcionando diámetros más gruesos y firmes. El rendimiento y las variables bromatológicas no presentaron diferencia entre los tratamientos, sin embargo, se produjo un forraje de buena calidad. En promedio las hojas presentaron el 13.56 % de cenizas, 70.15 % de total de nutrientes digestibles, 93.16 % de digestibilidad in vitro de la materia seca, 19.72 % de fibra detergente neutra, 25.35 % de fibra detergente ácida y 24.15 % de proteína cruda.

Residue and Potassium Management Strategies to Improve Crop Productivity, Potassium Mobilization, and Assimilation under Zero-Till Maize–Wheat Cropping System

Understanding of the potassium (K) nutrient cycle and its microbial transformation of unavailable forms of soil K to plant-available K is crucial in any agroecosystem for strategic nutrient management through inorganic fertilizer, crop residue (CR), and microbial applications. Therefore, the present investigation was undertaken to study the effect of crop residue and K management practices on crop productivity, K mobilization from native soil K-pool, and crop assimilation of K under a zero-till maize–wheat cropping system. The experiment consisted of four residue levels (0, 2, 4, and 6 Mg ha−1) and five K levels (0, 50%, 100%, 150% RDK [recommended dose of K] and 50% RDK + potassium solubilizing bacteria, KSB). Results showed that CR retention at 6.0 Mg ha−1 significantly improved grain yield (of maize by 10.17%; wheat by 9.87%), dry matter accumulation, K uptake and redistribution in native soil K pools (water soluble K (WSK), exchangeable K (EK) and non-exchangeable K (NEK)) at 30 and 60 days after sowing and at harvest as compared to no CR. Among the K management, 50% RDK+KSB reported significantly higher grain yield (of maize by 26.22%; wheat by 24.70%), dry matter accumulation, K uptake, and native K pools (WSK, EK, and NEK) at different growth stages compared to no K. Total K did not differ significantly due to residue and K management. The highest actual change of K reported with 6.0 Mg ha−1 CR (51 kg ha−1) and 50% RDK+KSB (59 kg ha−1) over control. Significant (p ≤ 0.01) positive correlation was found among grain yield, dry matter accumulation, K uptake, the actual change in K and different native K pools. It can be concluded that retention of 6 Mg ha−1 CR and supply of 50% K through inorganic fertilizer along with seed inoculation of KSB biofertilizers, improved crop growth, productivity by enhancing K assimilation as a consequence of the release of non-exchangeable K and through the application of CR and K treatments under a zero tillage maize–wheat system.

Growth, yield and quality of strawberry as affected by fertilizer N rate and biofertilizers inoculation under greenhouse conditions

Balanced plant nutrition is vital to increase crop yield and reduce costs of cultivation. This study tried to verify the influence of Nitrogen (N) in combination with biofertilizers on plant growth, yield and the quality of strawberry grown under greenhouse at the research farm of the Department of Horticulture, Chaudhary Charan Singh Haryana Agricultural University (CCS HAU) Hisar, Haryana (India). The treatments involved four fertilizer N rates of 0, 80, 100 and 120% recommended dose of nitrogen (RDN) plant−1 and two biofertilizers (Azospirillum and Azotobactor) inoculation, in a complete randomized design with five replications. Application 100% RDN per plant was significantly correlated with the maximum plant growth and yield characters, which was the main determinant of yield of strawberry. The maximum fruit yield (288.15 and 318.62 g/plant) was observed under 100% RDN, with increasing N rate, the yield was decreased during both the years of study. Fruits with maximum total soluble sugars (TSS), anthocyanin content and lower acidity were noted with the application of 120% RDN, while the maximum ascorbic acid content was estimated in fruits harvested from the plants were supplied with 100% RDN. Furthermore, biofertilizers had a significant effect on growth, yield and berry quality of strawberry and plants inoculated with Azotobacter, recorded maximum growth and yield attributes. As quality concerned plants inoculated with Azotobacter beared fruits recorded maximum values for quality parameters during the year 2017–18 and 2018–19. The combined application of Azotobacter along with 100% RDN showed better results in terms of all growth, yield and quality parameters, which was statistically at par with Azospirillum + 100% RDN during both the years. The study revealed that, N recommendation at a rate of 100% RDN per plant along with Azotobacter, Azospirillium inoculation suggested for sustainable strawberry production in this greenhouse conditions.

Phylogenetic Diversity of Trichoderma Strains and Their Antagonistic Potential against Soil-Borne Pathogens under Stress Conditions.

Trichoderma species are known as excellent biocontrol agents against soil-borne pathogens that cause considerable crop losses. Eight strains of Trichoderma were isolated from five Egyptian regions. They identified based on translation elongation factor-1α (TEF1) sequencing as four different Trichoderma species: Trichoderma asperellum, Trichoderma harzianum, Trichoderma viride, and Trichoderma longibrachiatum. Optimal growth conditions (temperature and media), and the phosphate solubilization capability of Trichoderma strains were evaluated in vitro. Further, the ability of these strains to antagonize Fusarium solani, Macrophomina phaseolina, and Fusarium graminearum was also evaluated. The results revealed that Trichoderma harzianum (Th6) exhibited the highest antagonistic ability against F. solani, M. phaseolina and F. graminearum with inhibition rates of 71.42%, 72.97%, and 84.61%, respectively. Trichoderma viride (Tv8) exhibited the lowest antagonism against the same pathogens with inhibition rates of 50%, 64% and 69.23%, respectively. Simple-sequence repeats (SSRs) and random amplified polymorphic DNA (RAPD) markers were used to evaluate the genetic variability of the Trichoderma strains. The results revealed that of 45 RAPD amplified bands, 36 bands (80%) were polymorphic and of SSRs amplified 36 bands, 31 bands (86.11%) were polymorphic. The amplification of calmodulin and β-1,3-endoglucanase was noted at 500 bp and 230 bp, respectively. Data indicated that T. viride (Tv8) had the highest phosphate solubilization index (10.0 mm), while T. harzianum (Th6) had the lowest phosphate solubilization index (4.0 mm). In conclusion, T. harzianum (Th6) had the highest antagonistic activity in dual culture assay along with the growth rate; while T. viride (Tv8) had the highest phosphate solubilization activity. There are still gaps in obtaining new formulations, selecting potent Trichoderma strains to confirm disease control in planta. For improving Trichoderma recommendation in the organic agricultural system and sustaining the fertility of the soil, the field application of highly antagonistic biocontrol agents in different types of soil and plant species will be the first approach toward bio-pesticide treatments along with bio-fertilizer inoculation. Furthermore, secondary metabolites will be investigated for the most promising strains with the combination of different pathogens and application timing.

Response of polymers and biofertilizers on soybean (Glycine max) yield under rainfed condition

A field experiment was conducted to find out the response of polymers and biofertilizers on yield and quality of soybean (Glycine max L. Merrill) under rainfed condition at the Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India during 2015-16. The experiment was laid-out in split-plot design consisting three levels of polymer (Control, 5 kg/ha Nano clay-polymer composite (NCPC) and 5 kg/ha Hydrogel) in the mainplots and four levels of biofertilizer inoculation (Control, Rhizobium japonicum, Phosphate Solubilising Bacteria (PSB) and Mycorrhiza) were taken in sub-plots with three replications. Results indicated that the application of polymer @ 5 kg NCPC/ha improved growth parameters, yield attributes, yields, nutrient content, uptake, quality of seed in terms of protein and oil content. However, the application of 5 kg/ha Hydrogel was statically at par on all the parameters. Moreover, amongst the biofertilizers response was found significant on the growth parameters, yield attributes, yield quality parameters, nutrient content and their uptake. Their conjoint application is beneficial to farmers for sustaining the crop productivity in the rainfed condition of eastern Uttar Pradesh, India.

INFLUENCE OF ARBUSCULAR MYCORRHIZAL FUNGI AND SOIL AMELIORANTS ON THE MYCORRHIZAL COLONIZATION, CHLOROPHYLL CONTENT, AND PERFORMANCE GROWTH OF TWO TROPICAL TREE SEEDLINGS GROWN IN SOIL MEDIA WITH HIGH ALUMINUM CONTENT

Aluminum is one of heavy metals and its availability is correlated with low soil pH, such as in acidic soil as well as post mining soil and become limiting factors for plant growth. MycoSilvi is a biofertilizer inoculant product containing arbuscular mycorrhizal fungi enriched with Mycorrhizal Helper Bacteria’s (MHBs) designed for improving plant growth on post-mining soil media with low pH and high aluminum content. This study was conducted to determine the potential use of three variants of MycoSilvi, both single or in combination with soil ameliorant to enhance Albizia chinensis (Osbeck) Merrill and Pongamia pinnata (L.) Pierre growth. This study was conducted by randomized complete design with factorial scheme in a greenhouse for 4 months. The first factor consisted of four different levels based on MycoSilvi (M) inoculation: control (M0); MycoSilvi variant 1 (M1), MycoSilvi variant 2 (M2) and MycoSilvi variant 3 (M3). The second factor consisted of four levels based on the addition of lime and compost to soil medium: control (L0C0), addition of lime (L1C0), addition of compost (L0C1) and addition of lime and compost (L1C1). Data was analyzed using analysis of variance (ANOVA). Total chlorophyll content as indicated by leaf greenness index, height, steam diameter, biomass, root colonization and P accumulation on both plant species were observed after 12 weeks of planting. The results showed that the MycoSilvi inoculation differently colonized the roots and increased P uptake, leaf greenness index and growth of both plants species. The addition of lime and compost increased the mycorrhizal roots colonization, P uptake, leaf greenness index and plant growth of both plants’ species. The best result was obtained from the combination treatment of MycoSilvi variant 3, lime and compost

Effect of Sulphur and Biofertilizer in Nutrient Uptake by Sesame and Microbial Population in Red and Lateritic Soil of West Bengal

The study was conducted in red and lateritic soils of West Bengal during pre-kharif season of 2016 on sandy loam soil of Agricultural Farm, Palli Siksha Bhavana, (Institute of Agriculture), Visva-Bharati, Sriniketan, West Bangal. The experiment was laid out in Randomized Block Design (RBD) with three replications using four levels of sulphur (0, 15, 30 and 45 kg ha-1) and single and dual inoculation of bio fertilizers to study the nutrient uptake by sesame and soil fertility status along with microbial population before and after harvest of crop. The results showed highest value of different nutrients uptake viz., Nitrogen, Phoshorus, Potasium and Sulphur with higher dose of fertilizer along with Azotobacter and PSB. The number of nitrogen fixing bacteria i.e. Azotobector and Phosphorus Solubilizng Bacteria (PSB) in soil increased due to inoculation of seed with biofertilizer. The seed inoculation exerted significant effect on number of nitrogen fixing bacteria and PSB in soil. The study suggested that the combined application of organic and inorganic fertilizer in sesame cultivation in red and laritic soils will exerts significant yield through important implications in nutrient uptake by sesame for its improved nutrition and improved productivity of soil.

Increase in phenolic compounds of Coriandrum sativum L. after the application of a Bacillus halotolerans biofertilizer.

There is an urgent need for a new sustainable way of satisfying the increasing demand for food worldwide. One of the main challenges is replacing chemical fertilizers with biofertilizers, which include plant root-associated beneficial microorganisms. The present study reports, for the first time, the effects of SCCPVE07 bacterial strain with respect to improving not only plant development, but also the nutritional content and bioactive compounds content of Coriandrum sativum L., one of the most economically important crops, even for plant growth under salinity stress. Innoculated coriander plants (C. sativum L.) showed an increase in potassium, carbon, calcium and iron content. A significant improvement in phenolic compounds contents was also observed. The contents of 5-O-caffeoylquinic acid, cinnamic acid, 4-methoxy-cinnamic acid hexoside, K-3-O rutinoside, Q-3-O-rutinoside, Q-3-O-glucoside and Q-3-O-glucuronide were significantly enhanced. Moreover, an efficient bacterial root colonization and a noted growth promotion were demonstrated. Bacterial genome was sequenced and analysed. Gene coding related to Plant growth promotion (PGP) mechanisms and proteins involved in plant defence from salinity or in the metabolism of phenolic compounds, such as quercetin 2,3-dioxygenase and phenolic acid decarboxylase, were identified. The results obtained in the present study show, for the first time, the beneficial effects of the inoculation of a bacterial Bacillus halotolerans biofertilizer on coriander crops with respect to increasing the content in bioactive compounds and plant development. © 2020 Society of Chemical Industry.

A potential antifungal and growth-promoting bacterium Bacillus sp. KTMA4 from tomato rhizosphere

Plant growth-promoting rhizobacteria are indigenous beneficial bacteria that will enhance plant growth as well as suppress phytopathogens. In the present study, the isolate KTMA4 showed the highest inhibition against major phytopathogens of tomato; Fusarium oxysporum (66%) and Alternaria solani (54%) after seven days of incubation. Analysis of the 16S rRNA gene sequence revealed that the isolate KTMA4 is Bacillus cereus (MG547975). The isolate produced in vitro plants growth-promoting factors such as Indole-3-acetic acid, ammonia, catalase, siderophore and 1-aminocyclopropane-1-carboxylate deaminase and it has nitrogen fixation ability. The bacterial strain has also produced lytic enzymes such as amylase, cellulase, xylanase, lipase, and protease. Moreover, the bacterium Bacillus cereus KTMA4 effectively produced biofilm, biosurfactants and salt-tolerant (5% NaCl). The bacterium exhibited intrinsic antibiotic resistance. The in vivo studies using tomato plants grown from seeds treated with the bacterial strain KTMA4 demonstrated an enhancement in seed germination percentage (86.66 ± 2.88) and vigour index (637.5 ± 21.65) over the uninoculated control (germination percentage- 28.33 ± 2.88 and vigour index- 42.5 ± 4.33). 60 days of greenhouse study revealed that the bacterial isolate enhanced the plant growth significantly (P ≤ 0.05) compared to the uninoculated control and the treated plants. Therefore the study suggests that the newly isolated rhizosphere bacterial strain can be used as a potential biocontrol agent against a multitude of fungal pathogens as well as a biofertilizer inoculant for tomato cultivation.

Soil fertility, macro and micro nutrient uptake and their use efficiencies under integrated nutrient management in groundnut (<em>Arachis hypogaea </em>L.)

A field experiment entitled “Soil Fertility, Macro and Micro Nutrient Uptake and their Use Efficiencies under Integrated Nutrient Management in Groundnut (Arachis hypogaea L.) was conducted during kharif season of 2017 at research farm, COA, Gwalior on sandy clay loam soil to study the response of groundnut fertilizers and biofertilizers. Four fertility levels viz., 25, 50, 75 and 100% RDF and three biofertilizer inoculation viz., no bio-formulations (B1), liquid Bio-NPK + Zn solubilizing bacteria (B2) and bio-grow (B3) to groundnut in 12 treatment combinations replicated thrice in split plot design. The yield and nutrient uptake (N, P, K, Zn) was significantly highest with 100% RDF and liquid Bio-NPK + Zn solubilizing bacteria. Nutrient use efficiencies for macro nutrients were highest with 25% RDF and liquid Bio-NPK+ Zn solubilizing bacteria. Highest status of N, P and K in soil recorded with 100% RDF and bio-grow inoculation. Available zinc in soil was non-significant to different fertility levels but biofertilizer inoculation significantly improved Zn status of soil.

STUDIES ON PEANUT BRADYRHIZOBIUM BROTH INOCULA AS AFFECTED BY IRRIGATION WATER QUALITY IN NEWLY RECLAIMED DESERT SOILS.

Peanut being a leguminous crop is capable of fixing atmospheric nitrogen. The present investigation had been carried out in order to study and evaluate the efficiency of both liquid and solid inoculum of Bradyrhizobium ssp (N2-fixing bacteria) alone or with plant growth promoting rhizobacteria (PGPR); Azotobacter chroococcum DSM 2286, as co-inoculation to reduce the negative impact of salinity of irrigation water (Nile Water (563 mg L-1) (W1), Groundwater artesian well, about 1000 mgL-1 (W2) and Groundwater artesian well about 2000 mgL-1 (W3), were collected from cultivated regions of Sadat city.) on peanut plants grown in cultivated sandy soils. Nodulation, fresh and dry weights of the growing plants and their elemental composition, mainly contents of nitrogen, phosphorus, potassium, manganese, zinc and Iron, yield, yield components as well as quality traits of the seed and oil of two peanut cultivars grown in sandy soils were determined. The biofertilizers inoculation treatments as follows: 1-Control treatments (without any biofertilizers inoculation). 2- Inoculation by solid Bradyrhizobium alone. 3-Inoculation by liquid Bradyrhizobium alone. 4- Co-inoculation: by solid Bradyrhizobium + PGPR (Azotobacter chrococoum), and 5- Co-inoculation: by liquid Bradyrhizobium fertilization + PGPR (Azotobacter chrococoum). It could be concluded that inoculation by liquid Bradyrhizobium + Azotobacter chroococcum seems to be the recommended treatment for producing optimum seed and straw yield and other parameters studied. Likewise it achieved the least production costs, also reducing the harmful effects of salinity of soil and/or irrigation water. These in turn reflect an increase in dry matter yield and after that pod, seed and straw yield. However, this approach could be explored as an effective strategy with least production costs to improve salt tolerance index in peanut plants under drip irrigation system in newly reclaimed soils in Egypt.

Produção de feijão-caupi em função do emprego de inoculante e adubos orgânicos e mineral

RESUMO: O feijão-caupi é uma leguminosa amplamente cultivada, principalmente no Nordeste do Brasil. Em seu cultivo, geralmente se emprega fertilizantes minerais de alta solubilidade que podem causar inúmeros impactos ambientais, e elevar consideravelmente os custos de produção. Desta forma, práticas de cultivo que possam diminuir o uso de fertilizantes minerais devem ser estudadas e validadas. Assim, o objetivo deste trabalho foi avaliar componentes vegetativos e produtivos do feijão-caupi submetido à diferentes fertilizantes orgânicos, inoculante e mineral. Os tratamentos foram distribuídos em blocos casualizados, com nove tratamentos e três repetições: Testemunha (T), sem adubação; biofertilizante (B); inoculante (I); resíduo lácteo (R); biofertilizante + inoculante (BI); resíduo lácteo + biofertilizante (RB); resíduo lácteo + inoculante (RI); resíduo lácteo + inoculante + biofertilizante (RIB) e o formulado NPK (M). Os fertilizantes orgânicos e o inoculante isolados ou associados não contribuem com a produtividade do feijão-caupi. O uso da adubação mineral aumentou a produtividade do feijão-caupi.

Alterations in the Endophyte-Enriched Root-Associated Microbiome of Rice Receiving Growth-Promoting Treatments of Urea Fertilizer and Rhizobium Biofertilizer.

We examined the bacterial endophyte-enriched root-associated microbiome within rice (Oryza sativa) 55 days after growth in soil with and without urea fertilizer and/or biofertilization with a growth-promotive bacterial strain (Rhizobium leguminosarum bv. trifolii E11). After treatment to deplete rhizosphere/rhizoplane communities, washed roots were macerated and their endophyte-enriched communities were analyzed by 16S ribosomal DNA 454 amplicon pyrosequencing. This analysis clustered 99,990 valid sequence reads into 1105 operational taxonomic units (OTUs) with 97% sequence identity, 133 of which represented a consolidated core assemblage representing 12.04% of the fully detected OTU richness. Taxonomic affiliations indicated Proteobacteria as the most abundant phylum (especially α- and γ-Proteobacteria classes), followed by Firmicutes, Bacteroidetes, Verrucomicrobia, Actinobacteria, and several other phyla. Dominant genera included Rheinheimera, unclassified Rhodospirillaceae, Pseudomonas, Asticcacaulis, Sphingomonas, and Rhizobium. Several OTUs had close taxonomic affiliation to genera of diazotrophic rhizobacteria, including Rhizobium, unclassified Rhizobiales, Azospirillum, Azoarcus, unclassified Rhizobiaceae, Bradyrhizobium, Azonexus, Mesorhizobium, Devosia, Azovibrio, Azospira, Azomonas, and Azotobacter. The endophyte-enriched microbiome was restructured within roots receiving growth-promoting treatments. Compared to the untreated control, endophyte-enriched communities receiving urea and/or biofertilizer treatments were significantly reduced in OTU richness and relative read abundances. Several unique OTUs were enriched in each of the treatment communities. These alterations in structure of root-associated communities suggest dynamic interactions in the host plant microbiome, some of which may influence the well-documented positive synergistic impact of rhizobial biofertilizer inoculation plus low doses of urea-N fertilizer on growth promotion of rice, considered as one of the world's most important food crops.

Potency of Commercial Symbiotic Bio-Fertilizer Consortium for Mitigating the Olive Quick Decline Syndrome (OQDS)

The inoculation of soil with a bio-fertilizer (BF), with arbuscular mycorrhiza fungi, characterizes a Symbiotic (S) agriculture mode, aimed at promoting the yield and health of crops through modifications in the rhizosphere as well as in the plant phenotype. The main objective of this study was to reduce the incidence of Olive Quick Decline Syndrome (OQDS, involving Xylella fastidiosasubsp.pauca) that afflicts the olive groves in Apulia (Italy). Non-inoculated control (C) plants were compared with Symbiotic (S) plants inoculated with 20 kg ha-1 of Micosat F ®, through a 15 cm deep scarification, in the groves of seven farms covering an area of 27 ha. In addition to a visual observation of 484 plants, to obtain a gradation of the disease severity, some objective rapid type methods were utilized to survey the plants and soil , namely leaf pH, NIR tomoscopy of the leaves, hay-litter-bag probes coupled with NIR spectroscopy and the prediction of soil induced respiration. The fingerprinting of the S and C types of leaves and litter-bags was ascertained by means of the use of a random forest algorithm in the classification matrices. The results on the symptoms appeared variable: they were significantly mitigated in two groves out of six, but they were aggravated in one. All the rapid measurements became essentials in a “holistic” model which was able to explain over 95% of the average mitigation / null / aggravation response to BF inoculation. The holistic model gathers differential and compositional analyses of the leaf (pH, crude protein, water) and of the soil (respiration), but depends mainly on the fingerprinting of the C and S leaves and litter-bags. Two keys were identified for a successful inoculation: a high degree of variability of the soil conditions permitting hospitality for the BF with enhancement of the microbial activity in the S soil (lowering the fingerprint of the control litter-bags) and homogeneity of the leaves (with increases in the fingerprint of the S leaves treated with BF). In short, the inoculation of diseased plants with one BF consortium is far from being the ultimate remedy to mitigate OQDS in all situations. Further studies are needed, at a field level, to clarify the soil hosting capacity and to define the mycorrhizal and / or endophytic * plant * pathogen interactions, even using rapid methods.

1-Aminocyclopropane-1-Carboxylate: A Novel and Strong Chemoattractant for the Plant Beneficial Rhizobacterium Pseudomonas putida UW4.

Plant growth-promoting rhizobacteria (PGPR) and fungi-bacterial biofilms are both important biofertilizer inoculants for sustainable agriculture. However, the strongest chemoattractant for bacteria to colonize the rhizosphere and mycelia is not clear. Coincidentally, almost all the PGPRs possess 1-aminocyclopropane-1-carboxylate (ACC) deaminase (AcdS) and can utilize ACC as the sole nitrogen source. Here, we found that ACC was a novel, metabolic dependent and methyl-accepting chemoreceptor-involved chemoattractant for Pseudomonas putida UW4. The chemotactic response of UW4 to ACC is significantly greater than that to the amino acids and organic acids identified in the plant root and fungal hyphal exudates. The colonization counts of the UW4 acdS or cheR deletion mutants in the wheat rhizosphere and on Agaricus bisporus mycelia were reduced one magnitude compared with those of UW4. The colonization counts of UW4 on A. bisporus antisense ACC oxidase mycelia with a high ACC production significantly increased compared with A. bisporus, followed by the UW4 cheR complementary strain and the ethylene chemoreceptor gene-deletion mutant. The colonization counts of the UW4 strains on A. bisporus acdS+ mycelia with a low ACC production decreased significantly compared with A. bisporus wild type. These results suggested that ACC and not ethylene should be the strongest chemoattractant for the PGPR that contain AcdS.

Production of biofuel from sugarcane molasses by diazotrophic Bacillus and recycle of spent bacterial biomass as biofertilizer inoculants for oil crops

Abstract This study was designed to identify the most potent N2-fixing and biofuel producing Bacillus species. Four isolates were selected as the most efficient N2-fixing organisms which confirmed by nifH gene expression. These isolates were identified genetically by 16S rRNA as Bacillus thuringensis, Bacillus subtilis, Bacillus pumilus and Bacillus licheniformis. The highest biohydrogen production was 2450 and 2300 ml/L from 6% sugarcane molasses by B. thuringensis and B. subtilis respectively. Nitrogenase activity of B. thuringensis and B. subtilis were 1.4 and 1.3 μmol C2H4 min−1 mg protein −1 at 6% molasses. Ethanol production was 1.55 and 1.03 g/L, while butyric acid was 10.39 and 5.9 g/L at 6% molasses by B. thuringensis and B. subtilis at 6% molasses, respectively. Acetic acid formation was 1.1 and 0.55, lactic acid was 0.07 and 0.05, while butyric acid was 10.39 and 5.9 g/L at 6% molasses by B. thuringensis and B. subtilis, respectively. Spent bacterial biomass of the two Bacillus species were reused as a biofertilizer for enhancing the growth of sunflower and corn plants. Inoculation of sunflower and corn seeds with B thuringensis and B subtilis significantly increased dry weight, total protein, total carbohydrates and pigment contents over control plants. This enhancement could be attributed to the efficiency of biological N2-fixation due to nitrogenase activity of the tested Bacillus species. These results suggest that the possibility of interlinking biofuel technology with biofertilizer production by reusing N2-fixing spent bacterial biomass of Bacillus could be increase the economic feasibility of the bioenergy production from molasses.

Enhancement of Growth and Yield of <i>Arachis hypogeae </i>L. Using Different Biofertilizers

The field experiment was conducted in split design with three replicates in Arunagirimangalam village, Thiruvanamalai District to study the effect of groundnut haulm compost of single and combined inoculation of FYM, different biofertilizers (Azotobacter, Azospirillum, Phosphobacteria, Rhizobium) on growth, photosynthetic pigments, biochemical properties and yield of Arachis hypogeae L. The results of this experiment revealed that groundnut haulm with combined inoculation of biofertilizers significantly increased growth, photosynthetic pigments, biochemical and yield parameters of the test crop. Among various combinations, single inoculums of groundnut haulm performed better than control while groundnut haulm with combined inoculation of Rhizobium found better over single inoculation treatments. In general, it could be concluded that groundnut haulm compost and mixed with Rhizobium may be a good tool to improve the crop yield productivity and quantity and soil health.

Enhancement of Growth and Yield of <i>Arachis hypogeae </i>L. Using Different Biofertilizers

The field experiment was conducted in split design with three replicates in Arunagirimangalam village, Thiruvanamalai District to study the effect of groundnut haulm compost of single and combined inoculation of FYM, different biofertilizers (Azotobacter, Azospirillum, Phosphobacteria, Rhizobium) on growth, photosynthetic pigments, biochemical properties and yield ofArachis hypogeaeL. The results of this experiment revealed that groundnut haulm with combined inoculation of biofertilizers significantly increased growth, photosynthetic pigments, biochemical and yield parameters of the test crop. Among various combinations, single inoculums of groundnut haulm performed better than control while groundnut haulm with combined inoculation ofRhizobiumfound better over single inoculation treatments. In general, it could be concluded that groundnut haulm compost and mixed withRhizobiummay be a good tool to improve the crop yield productivity and quantity and soil health.

Effect of Biofertilizers and Phosphorus Levels on Soil Fertility, Yield and Nodulation in Chickpea (Cicer arietinum L.)

The field experiment was conducted to evaluate the effect of biofertilizers and phosphorus (P) levels on soil fertility, yield and nodulation in chickpea at Instructional Farm of Narendra Deva University of Agriculture and Technology, Kumarganj, Faizabad, Uttar Pradesh, India during rabi season 2015–16. The nine treatments comprised of biofertilizers (0, PSB and AM) and three P levels (0, 40 and 60 kg P2O5 ha−1) were tested in randomized block design replicated as thrice. The experimental soil having silty loam in texture, pH (1: 2.5) 8.24, EC 0.34 dS m−1, organic carbon 3.5 g kg−1, available nitrogen (N) 180, P 18.2 and potassium (K) 226 kg ha−1. The plant spacing was row to row 30 cm and plant to plant 10 cm. The variety PG-186 was taken as a test crop. The yield, dry matter accumulation, number, fresh and dry weight of nodule and availability of N, P and K were increased with the increasing levels of P and with inoculation of biofertilizers. The maximum was received with the application of 60 kg P2O5 ha−1 followed by 40 kg P2O5 ha−1. Among the application of biofertilizers (PSB and AM), the maximum were recorded with the application of AM which was statistically at par with PSB and significantly superior over the without inoculation.

Response of some Sesame Cultivars (Sesamum indicum L.) to Bio and Organic Fertilizers under Toshka Conditions

In order to study the effect of three Sesame cv. (Sohag1, Shandaweel 3 and Giza 32), two Bio-fertilizer inoculation (Azotobacter and biogein) and three rates of organic fertilizer (5 m3, 10 m3 and 20 m3) compared with the control on seed yield and its components as well as Chlorophyll content growing during 2015 and 2016 seasons, so, two field experiments were carried out in the Desert Research Center (D.R.C.) Experiment Station at Toshka (Abu Simbel) Aswan Governorate, South Egypt. Obtained results showed that. Shandaweel 3 cultivar produced the maximum number of capsules/plant, number of seed/capsules and seed yield than all other cultivars. Increasing application of organic fertilizers from 5 up to 20 m3 caused significant increament in chlorophyll content, plant height, number of seed/capsules, number of capsules/plant, 1000- seed weight; and seed yield compared with other organic fertilizer treatments. Application of Azotobacter as bio-fertilizer caused an increament concerning all characters studied. The interaction between cultivars and organic manures treatments showed a significant effect on chlorophyll content, plant height; number of capsules/plant and seed yield. Shandaweel 3 cultivar applied with 20 m3 organic manures proved to have the best results. Moreover, all studied traits were significantly affected by the interaction between sesame cultivars and bio- fertilizer. Concerning, the interaction between organic manures and bio-fertilizers treatments, maximum seed yield were 524 and 478 (kg/fed.) during the two seasons respectively, recorded when organic manures application of 20 m3 along with Azotobacter agent were applied. It could be concluded that sesame cultivar Shandaweel 3 cultivar fertilized with 20 m3 organic fertilizers and Azotobacter as bio- fertilizers is recommended under semi-arid conditions of the Toshka, South Egypt