Phosphorus Solubilizing Bacteria Research Articles

Effectiveness of Phosphorus Solubilizing Bacteria on Enhancing Phosphorus Availability from Minjingu Phosphate Rock to Maize in Slightly Acid to Neutral Soils

The aim of this one-year field study was to evaluate the impact of phosphorus solubilizing bacteria (PSB) on increasing the availability of phosphorus locked up in insoluble Minjingu phosphate rock for the maize crop (Zea mays L.) in high soil pH. The study was carried out during one wet season in Nghumbi and Mlali villages in Kongwa District in the Dodoma Region, Tanzania. Based on the pH of their soil and the limiting nutrients, two farms from Mlali village and five from Nghumbi village were chosen at random for field trials. To determine the fertility status, composite soil samples were collected from the chosen farms and examined in a lab. Target treatments included the application of PSB inoculum in combination with various rates of Minjingu phosphate rock (MPR) (0, 20, 30, 40, and 60 KgP ha-1) as a basal fertilizer, placed beneath maize seed and covered with a thin layer of soil. Using a fully randomised block design, the treatments were set up three times. Inadequate levels of N, P, K, and Zn were found in the research area's soil samples. Results indicated the main effect of fields’ characteristics from field No.2 had the highest yield to other fields with significantly (P< 0.001) highest grain yield being 4.4 t ha-1, biological yield of 5.6 t ha-1, and Straw P uptake of 19.63 kg ha-1. Using P or an inoculant (Mx) produced a negligible yield of grain and straw, according to the major effect of treatments. For the studied variables, none of the treatments showed any significant (P =0.427) interaction effects. An intriguing revelation that the study's maize response to native P is provided by interaction effects area is a factor of soil and amount of P released to the soil. We recommend more research on PSB for more than one season in high soil pH before ascertaining the technology to farmers.

Sustainable basmati rice yield and quality enhancement through long-term organic nutrient management in the Indo-Gangetic Plains

Context or problemThe extensive use of chemical fertilizers and pesticides in modern agriculture, particularly since the green revolution, has led to profound consequences for agricultural ecosystems. This approach, while initially boosting yields, has disrupted soil health, biodiversity, and environmental balance. Moreover, it contributes silently to global climate change by releasing greenhouse gases. These challenges underscore the urgent need for a shift towards sustainable agricultural practices to safeguard soil health, biodiversity, and human nutrition while mitigating the impacts of climate change. Objective or research questionThe primary objective of this study is to assess the impact of the long-term (seventeen years) application of organic nutrient management on the physicochemical properties of basmati rice soil and its nutritional quality. The study aims to understand the effectiveness of different organic nutrient management practices in mitigating the negative consequences associated with conventional agricultural practices. MethodsThe experiment used a strip-plot design with three replications, assigning two cropping systems (basmati rice-wheat-green gram and basmati rice-wheat-sesbania) to vertical strips. Seven nutrient management practices, including control, farmyard manure (FYM), vermicompost, farmyard manure + crop residues, vermicompost + crop residues, farmyard manure + crop residues + biofertilizers, and vermicompost + crop residues + biofertilizers [nitrogen-fixing Azospirillum, phosphorus-solubilizing bacteria (PSB), potassium-solubilizing bacteria (KSB), and a cellulolytic culture (Aspergillus awamori, Trichoderma viride, Phanerochaete chrysosporium, and Aspergillus wululens)] were applied to the horizontal strips. ResultsThe findings show that the cropping system with sesbania green manure significantly improved soil physicochemical attributes, nutritional content, and basmati rice yield compared to the green gram-based system. Continued application of organic manures, crop residues, and biofertilizers notably enhanced soil fertility, grain quality, and basmati rice productivity. The combined use of vermicompost, wheat residue, biofertilizers, and sesbania green manure treatment increased organic carbon content by 78.7% over the control, and soil available nitrogen, phosphorus, and potassium by 38.3–54.9%, 57.6–143.8%, and 27.9–64.1%, respectively. Additionally, it augmented diethylenetriamine pentaacetic acid extractable iron, zinc, manganese, and copper content by up to 44.2%, 28.5%, 57.9%, and 71.0%, respectively. Co-application of the above organic sources also significantly enhanced grain and straw yields by 74.5–80.1% and 46.1–50.0%, respectively, compared to the control. ConclusionsEnhancing Basmati rice yield and quality in the Indo-Gangetic Plains can be sustainably achieved through sesbania green manuring and organic practices. Positive correlations with key soil parameters emphasize the significance of organic farming for long-term sustainability. Implications and significanceThe study suggests that adopting organic practices, including sesbania green manuring and combining organic inputs, can alleviate the adverse effects of conventional farming on soil health, biodiversity, and climate change. This aligns with the broader goal of establishing sustainable production and consumption in basmati rice-based cropping systems.

Response of green gram [Vigna radiata (L) Wilczek] to application of biofertilizers and phosphorus

The present study was carried out at the Crop Research Centre, Carrier Point University, Kota (Rajasthan), during the kharif season of 2020 and 2021 to assess the effect of phosphorus, rhizobium and phosphate solubilizing bacteria on growth and yield attributes of green gram. Significantly increase in growth, yield attributes and yield of green gram were recorded with the application of phosphorus 50 kg P2 O5 /ha. In case of biofertilizers (PSB, Rhizobium and PSB + Rhizobium), all growth and yield attributes and yield were increased significantly. However, among treatment combinations, the maximum values of these parameters were observed with 50 kg P2 O5 /ha + biofertilizers (PSB + Rhizobium) in comparison to all other treatment combinations. The net returns and B: C ratio were also higher under 50 kg P2 O5 /ha + biofertilizers (PSB + Rhizobium).

Effects of organic nutrient management on aromatic rice (Oryza sativa)-linseed (Linum usitatissimum) sequence

The experiment was conducted during 2019 and 2020 at the Instructional-cum Research (ICR) Farm, Assam Agricultural University, Jorhat, Assam to study the impact of different combinations of organic nutrient sources on aromatic rice (Oryza sativa L.) (rainy-kharif) and their residual effect on linseed (Linum usitatissimum L.) (winter- rabi) crop for developing a double cropping sequence for rice growers of Assam with organic management. The experiment comprised three aromatic rice cultivars, viz. Kola joha, Keteki joha and Chakhao poireiton and five combinations of organic nutrient sources. Out of the organic nutrient sources, application of N @30 kg/ha through vermicompost along with pre-season green manuring of Sesbania bispinosa and root dip treatment of rice seedlings with Azospirillium and phosphorus solubilising bacteria @3.5 kg/ha each (N3) resulted the highest number of panicles/ m2 (216.72 in 2019 and 223.96 in 2020), highest yield of rice (30.26 q/ha in 2019, 32.58 q/ha in 2020 grain yield and 65.99 q/ha in 2019, 68.98 q/ha in 2020 straw yield). The highest seed yield (394.52 kg/ha in 2019, 416.97 kg/ha in 2020) and stover yield (890.09 kg/ha in 2019, 896.63 kg/ha in 2020) of succeeding relay sown linseed were recorded with the N3 treatment. The highest available N (250.10 kg/ha), P2O5 (20.40 kg/ha) and K2O (140.06 kg/ha), organic C (0.65%), soil organic carbon (SOC) stock (13.29 t/ha), soil microbial biomass carbon (SMBC) (183.43 µg/g of soil) in soil were recorded with the N3 treatment after harvest of linseed in 2020. The study affirmed the suitability of rice-linseed cropping sequence for efficient utilization and conservation of resources.

Production of Bamboo Source Microbial Fertilizer and Evaluate Its Effect on Soil Organic Carbon Fractions in Moso Bamboo Plantations in South China

Bamboo shoot processing wastewater (BBPW) is rich in organic matter and organic acids and can be used as a nutrient source for microbial growth and biofertilization. In this study, Pseudomonas K22-D and Terribacillus goriness CS3 were isolated from bamboo forest soil with plant growth-promoting properties. Biofertilizers were prepared by inoculating bacteria into BBPW, and the effects of their application in a bamboo forest were evaluated. The chemical oxygen demand, TOC, TN, and NH4-N contents decreased after inoculation, indicating that the bacteria were able to degrade macromolecules in BBPW. The BBPW biofertilizer produced by mixed bacteria (CS3 + K22-D) significantly improved the soil organic carbon and mineral-associated organic carbon content and reduced the pH, alkali-hydrolysable nitrogen, available phosphorus, and available potassium content of the soils in the bamboo forest, which might be attributed to the high C:N ratio and microbial synergism in the biofertilizer and the fast growth period of bamboo shoots. Notably, the CS3 biofertilizer significantly increased soil-available phosphorus (90.25%), and the K22-D biofertilizer significantly decreased soil-available phosphorus (70.33%) compared with CK, suggesting that the presence of inorganic phosphorus-solubilizing bacteria can promote soil P. We believe that the return of inoculated bamboo shoot processing wastewater to bamboo plantations can be an eco-friendly, sustainable practice for bamboo forest management.

Isolation and Characterization of Phosphorus Solubilizing Bacteria from Millet Rhizosphere in Lafia metropolis

Phosphorus is an essential, but often unavailable nutrient for plant growth in the soil due to its low solubility. Phosphorus solubilizing bacteria (PSB) convert insoluble forms of phosphorus into soluble forms that can be taken up by plants. The study aimed to isolate and characterize PSB from the rhizosphere of millet plants in Lafia, and to evaluate their potential for improving soil fertility and crop productivity. Soil samples were collected from four different locations and plated on Pikovskaya's agar medium. PSB colonies were identified based on their ability to produce clear zones around them. The PSB isolates were further characterized by morphological, biochemical, and molecular methods. The phosphate solubilizing activity and plant growth-promoting traits of the PSB isolates were also assessed. The PSB isolates were tested for their effect on the growth of millet seedlings in pots. The results showed that 16 PSB isolates belonging to four genera (Bacillus, Pseudomonas, Enterobacter, and Klebsiella) were obtained from the soil samples. The PSB isolates exhibited varying degrees of phosphate solubilizing activity, ranging from 11.2 to 81.6 mg/L. The PSB isolates also showed positive results for the production of indole acetic acid, ammonia, hydrogen-cyanide, and siderophore. The PSB inoculation significantly increased the shoot and root lengths, and fresh and dry weight of the millet seedlings. The study concluded that the PSB isolates from the millet rhizosphere in Lafia could enhance soil phosphorus availability and millet growth. The study recommended further research on the field application and optimization of the PSB inoculation.

Genome‑Wide Identification and Expression Analysis of SPX Domain-Containing Gene Subfamily in Response to Phosphorus-Solubilizing Bacteria in Apple (Malus domestica)

AbstractPhosphate is one of the major elements that significantly affects fruit yield and quality. The aim of the study was to determine whether using phosphorus-solubilizing bacteria could produce high-quality apple nursery trees. Five different treatments were tested on a “Granny Smith” apple cultivar that was grafted onto an M.9 rootstock. These were 100% P, 50% P, 50% P + Bacillus megatarum (plant growth promoting rhizobacteria, PGPR), 0%P, and 0%P + PGPR. The study also identified the SPX gene family, which is essential for plant growth and development and responds to phosphorus (P) stress. A total of 72 SPX genes were identified in different plant species based on structural and phylogenetic analysis. The apple genome contains seven different SPX genes distributed on five of the 17 chromosomes. Gene structure and motif analysis showed that SPX genes show a relatively conserved exon/intron arrangement and motif composition in five different species: apple, strawberry, peach, apricot, and grape. Protein–protein network analysis showed that SPX proteins are closely related to proteins involved in P metabolism in apple. The digital expression profiles of MdSPX genes among 47 apple tissues were characterized to provide insight into their potential functions. RT-qPCR revealed that the expression level of all MdSPXs was significantly downregulated in 50% P + PGPR treatments, indicating that 50% P combined with PGPR is effectively taken up by the plant, saving it from Pi starvation. These results not only confirm the key role of MdSPXs in Pi homeostasis and the Pi signaling pathway but also clarify the importance of Pi-solubilizing bacteria in plant nutrition.

INTEGRATED USE OF PSB AND ORGANIC FERTILIZERS TO IMPROVE YIELD AND QUALITY OF BELL PEPPER (Capsicum Annum L.) CV. GREEN WONDER

Bell pepper is an important Solanaceous crop that is cultivated all around the globe for its economical and nutritional value. In Pakistan, it is cultivated mainly in Sindh and Punjab province of Pakistan. However,   average yield ha-1 is quite low as compared to the rest of the world. One of the main reasons for this low yield is poor phosphorous status. The current study was conducted to estimate the effects of organic application combined with PSB biofertilizers (Phosphorus Solubilizing Bacteria) on growth and yield of bell pepper. Organic amendments included leaf compost (LC), farmyard manure (FYM) and poultry manure (PM). Bell pepper cultivar “Green Wonder” was used as test crop. FYM and PM showed better results as compared to LC in most of the measured parameters. Plant height in FYM and PM was 59.79 and 59.07 cm while PSB application produced 67.84 cm high plants. Maximum leaf area was 176.98 cm2 that for FYM and was further increased up to 204.43 cm2 when supplemented with PSB. Bell pepper yield was also maximum in FYM i.e. 1211.7 g while PM showed a value of 1077.6. g. However, when PSB was applied in combination with these treatments, yield plant-1 was further increased up to 1393.4 and 1227.6 g, respectively. Total soluble solids were statistically at par among all the organic amendments but higher than control. Ascorbic acid was maximum in PM (58 mg 100 g-1) and followed by FYM (55.53 mg 100 g-1). PSB application showed a value of 72.46 mg 100 g-1. It is recommended from these results that application of organic amendments and PSB should be practiced enhancing that yield and quality of bell pepper.

Concurrent effect of phosphorus, nanoparticles and phosphorus solubilizing bacteria influences root morphology, soil enzymes and nutrients uptake in upland rice (Oryza sativa L.)

Phosphorus and zinc are important nutrient elements of concern in upland rice production. To determine the suitable combination of phosphorus, nanoparticles (NPs), and bio-fertilizer application as an alternative nutrient management approach in upland rice cultivation, a Polyvinyl Chloride (PVC) column experiment was conducted under controlled conditions in 2015. The treatments consisted of three phosphorus levels, two foliar sprays of NPs (ZnO and TiO2), and PSB seed treatment. The results indicated that the combined application of P (50 kg ha−1), ZnO NPs (500 ppm), and PSB seed treatment (20 g kg−1) improved the root system architecture traits of rice (total root length: 3.73–6.74%, diameter: 8.57–22.22%, and volume: 3.40–3.70%) at depths of 0–30 cm and 30–60 cm, compared to higher P + TiO2 NPs + no PSB. Consequently, this combination led to an enhancement in photosynthetic leaf area (by 3.3%), tiller numbers (by 7%), and dry matter production (by 35.5%). The favorable root growth resulting from the application of higher P and PSB enhanced zinc uptake by rice grains (by 38.44%) and straw (by 26.99%). Furthermore, the supplemental application of PSB improved the activity of soil enzymes such as dehydrogenase and phosphatase. As a result, maximum phosphorus use efficiency (PUE; 31.5%) was achieved through the combined application of P (50 kg ha−1) × ZnO NPs × PSB. In conclusion, this study demonstrated the beneficial effects of an integrated approach involving phosphorus, PSB, and metal oxides (ZnO NPs) as a fertilizer management strategy to enhance the total biomass and PUE of upland rice.

Integrated Nutrient Management Strategies: Unraveling the Impact of Bio-Fertilizers and Traditional Fertilizers on Soybean (Glycine max) Productivity

The study investigated the impact of different treatments on soybean growth and productivity, focusing on plant height and various growth parameters. Notably, Treatment T6, incorporating cow dung, Rhizobium, and Phosphorus-Solubilizing Bacteria (PSB), consistently outperformed other treatments. At 40 days after sowing (DAS), T6 exhibited the highest plant height, a trend sustained at 60 DAS and harvest. This superiority was attributed to the synergistic effect of the bio-fertilizer components. The control (T1) consistently had the shortest plants. In terms of productivity, T6 consistently excelled across parameters such as number of branches (4.12), nodules per plant (29.33), number of pods (33.33), pod length (4.82), seeds per pod (4.29), and seed yield (1.87 t/ha). Additionally, T6 demonstrated the highest protein (39.41%) and oil content (18.60%). While the recommended fertilizer dose (T2) showed improvement over the control, T6 surpassed T2, emphasizing the synergistic benefits of combining organic and microbial inputs. These findings highlight the potential of bio-fertilizers, particularly the combined approach, in enhancing soybean productivity. The study provides valuable insights for sustainable agricultural practices and optimizing fertilizer strategies for improved crop yields.

Species Diversity, Nitrogen Fixation, and Nutrient Solubilization Activities of Endophytic Bacteria in Pea Embryos

Endophytic bacteria, especially those that participate in nitrogen fixation, play critical roles in supplying essential nutrients for legume plant growth. Despite that there have been numerous investigations targeting bacterial microbiomes in legume roots and nodules, little is known about embryonic bacteria that facilitate plant nutrient utilization after seed germination. Here, we collected and investigated endophytic bacterial microbiome in edible pea (Pisum sativum) embryos using five representative cultivars and a pea sprout (shoot of pea [SHP]) control. Twenty-six nitrogen-fixing bacteria (NFB) were isolated from pea embryos, with three strains found in fresh grain pea (FGP) and snow pea (SP) exhibiting the strongest nitrogenase activity of above 85 nmol C2H4/mL/h. Some NFB isolates are also potassium-solubilizing bacteria (KSB) or phosphorus-solubilizing bacteria (PSB) utilizing inorganic and/or organic phosphorus. All 26 NFB showed variable levels (0.41 to 7.10 μg/mL) of indole-3-acetic acid (IAA) secretion. The nutrient-solubilizing NFB identified in our research are potential targets for biofertilizer development. They could be useful in converting nitrogen, potassium, and/or phosphorus into usable forms for the plants. At the microbiome level, high-throughput 16S ribosomal RNA (rRNA) sequencing of 40 bacterial collections from pea embryos generated 4234 operational taxonomic units (OTUs) using 97% identity as the threshold for clustering high-quality effective reads (valid tags). Analysis of OTU annotation results revealed similar species community structures, abundance, and diversity in most samples. Our embryo-derived endophytic bacterial pool provides a microbiome platform for seed dormancy and germination research of edible peas, as well as for digging new biofertilizer resources in general.

Rock Phosphate and Manures with Phosphorus Solubilizing Bacteria Increases the Growth, Yield and Phosphorus Uptake of Okra (Abelmoschus esculentus)

Phosphorus (P) is one of the most important plant nutrient for increasing soil productivity and sustainable crop production. A pot experiment was conducted to study the effect of seed inoculation by phosphorus solubilizing bacteria (PSB) and organic and mineral P fertilizers on growth, yield and P uptake of okra. Phosphorus was applied at the rate of 90 kg ha-1 in the form of poultry manure (PM); sheep manure (SM) and rock phosphate (RP). Nine treatments were allocated for the experiment having PM, SM and RP alone, organic manures with RP in combination, or a mix of the three with PSB. The result revealed that sole application of SM at three growth stages gave maximum root and shoot growth, which was 75 and 78% more from control respectively. It is concluded that Leaf area (36%), chlorophyll contents (62%), yield (60%) and P uptake (31%) of okra were significantly enhanced by the integrated use of PM+SM+RP+PSB at all growth stages over control. Complementary application of this inoculants with manures and RP most favored okra growth and yield and can be considered as an appropriate substitute for chemical P fertilizer in organic and sustainable agricultural system.

Integrated Effect of Organic Amendments and Chemical Fertilizers on yield of Groundnut and Soil Health Under Rainfed Condition

Although inorganic fertilizers increase the growth of crops, but their toxicity is the main concern due to their over utilization. To tackle this problem, the integrated application of organic amendment especially vermicompost, with NPK fertilizers would be a good choice. For this, the integrated effect of organic amendments including vermicompost (VC) and phosphorus solubilizing bacteria (PSB), and chemical fertilizers (NPK) on yield of groundnut and soil health, a field trial was done at the research area of Barani Agricultural Research Institute (BARI), Chakwal. The experiment was done with eight treatments in randomized complete block factorial design replicated thrice. The experimental data revealed that the treatment T8: Recommended dose of fertilizers (RDF) (NPK 20:80:60 Kg ha-1) + VC @ 4t ha-1 + PSB had superior effect on plant height (54.76.23%), number of plants per m2 (22.25%), number of pods per plant (61.90%), pod yield (83.25%) and haulem yield (86.02%) as compared to control. Similarly, a higher benefit cost ratio (BCR) was observed in T8 than rest of the treatments and control. Soil fertility indicators (OM, NO3-N, P and K) were improved, indicating the improvement in soil health with the combine application of VC, PSB and RDF. A combination of organic amendment, bio fertilizer, and inorganic fertilizer is necessary to optimize groundnut growth and yield attributes, as well as soil health.

Effect of the growth and yield attributes of sunflower and chickpea with responseto different doses and methods of Phosphorus Solubilizing Bacteria in combinationwith different Phosphorus levels

A study was conducted on sunflower and chickpea in sandy loam soils during Rabi 2020 at PJTSAU, Rajendranagar, Hyderabad. This study was focused to know the response of the liquid and powdered PSB on growthand yield attributes of sunflower and chickpea. For this experiment the treatment combination includes, different methods (liquid and powdered) and doses (@ 3 and 6 kg ha-1 for soil application and 50 ml L-1 for drenching) of Phosphorus Solubilizing Bacteria (PSB) along with different phosphorus levels. Phosphorus plays a key role in photosynthesis, metabolism of sugars, energy storage and transfer, cell division, cell enlargement and transfer of genetic information. Inoculation with PSB known to produce the growth hormones like Indole - Acetic Acid and Gibberillic Acid which might favour to increase plant height. The results reported that there was a significant effect of PSB on the plant height, Head diameter, number of pods/plant and non-significant effect on plant stand and test weight. Among, all the treatments the highest plant height (124.33 cm) and head diameter (16.23 cm) at maturity stage in sunflower was seen with 75% P + PSB @ 6 kg/ha and the highest plant height (51.13 cm) and number of pods/plant (26.07) at maturity stage in chickpea was seen with 50% P+ PSB @ 6 kg/ha. There was a non significant effect of PSB on plant stand and test weight. With the application of the PSB there was a reduction of the application of the phosphorus fertilizer to the extent of 25% in sunflower and 50% in chickpea. 

Complete genome sequence of Nguyenibacter sp. L1, a phosphate solubilizing bacterium isolated from Lespedeza bicolor rhizosphere.

Phosphorus (P) deficiency is a predominant constraint on plant growth in acidified soils, largely due to the sequestration of P by toxic aluminum (Al) compounds. Indigenous phosphorus-solubilizing bacteria (PSBs) capable of mobilizing Al-P in these soils hold significant promise. A novel Al-P-solubilizing strain, Al-P Nguyenibacter sp. L1, was isolated from the rhizosphere soil of healthy Lespedeza bicolor plants indigenous to acidic terrains. However, our understanding of the genomic landscape of bacterial species within the genus Nguyenibacter remains in its infancy. To further explore its biotechnological potentialities, we sequenced the complete genome of this strain, employing an amalgamation of Oxford Nanopore ONT and Illumina sequencing platforms. The resultant genomic sequence of Nguyenibacter sp. L1 manifests as a singular, circular chromosome encompassing 4,294,433 nucleotides and displaying a GC content of 66.73%. The genome was found to host 3,820 protein-coding sequences, 12 rRNAs, and 55 tRNAs. Intriguingly, annotations derived from the eggNOG and KEGG databases indicate the presence of genes affiliated with phosphorus solubilization and nitrogen fixation, including iscU, glnA, and gltB/D associated with nitrogen fixation, and pqqBC associated with inorganic phosphate dissolution. Several bioactive secondary metabolite genes in the genome, including pqqCDE, phytoene synthase and squalene synthase predicted by antiSMASH. Moreover, we uncovered a complete metabolic pathway for ammonia, suggesting an ammonia-affinity property inherent to Nguyenibacter sp. L1. This study verifies the nitrogen-fixing and phosphate-dissolving abilities of Nguyenibacter sp. L1 at the molecular level through genetic screening and analysis. The insights gleaned from this study offer strategic guidance for future strain enhancement and establish a strong foundation for the potential incorporation of this bacterium into agricultural practices.

Foliar application of Fe2O3 nanofertilizer on growth and yield of cauliflower (Brassica oleracea var. Botrytis L.) cv. Pusa Snowball K-1

The growth, yield, and quality of cauliflower (Brassica oleracea var. botrytis L.) cv. Pusa Snowball K-1 were studied using Fe2O3-nano fertilizer (Fe2O3-N) in combination with Azotobacter, Farmyard manure (FYM), and Phosphorus solubilizing bacteria (PSB). Hydrothermally synthesized Fe2O3 nanoparticles characterized with XRD, FTIR, and SEM. The experiment consisting 12 treatments viz. T1 (Fe2O3-N), T2 comprising of Fe2O3-N + FYM + Azotobacter + PSB, T3 (Fe2O3-N + Azotobacter + PSB), T4 (Fe2O3-N + FYM + Azotobacter), T5 (Fe2O3-N + FYM + PSB), T6 (Fe2O3-N + FYM), T7 (Fe2O3-N + Azotobacter), T8 (Fe2O3-N + PSB), T9 (PSB), T10 (Azotobacter), T11 (FYM), and T12 (control). Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. Application of Fe2O3-nano fertilizer (Fe2O3-N) along the Azotobacter, FYM, and PSB was shown encouraging growth effects to improve the cropping behavior. Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield.

Effect of Micronutrients and Biofertilizer Treatments on Yield and it`s Attributes of Coriander (Coriandrum sativum L.) cv. RCR-41

The current study, named "effect of micronutrients and biofertilizer on yield parameters of coriander Coriandrum sativum (L.) cv. RCR-41," is planned to be carried out in the Research Field, Department of Horticulture, College of Agriculture, Gwalior, M.P., during Rabi 2020-21 and 2021-22. The experiment was designed in a Completely Randomized Block Design (CRBD) with two factors concepts i.e., Micronutrients (ZnSO4 (0.5%), FeSo4 (0.5%), CuSo4 (0.5%), Biofertilizers (Phosphorus Solubilizing Bacteria (PSB), Azotobacter, Potassium Solubilizing Bacteria (KSB) and replicated three times and included three replications. At the time of coriander seeding, treatments combinations including RDF doses of fertilisers and biofertilizers were used. The results showed that treatment M1 (ZnSO4 @ 0.5%) was the optimum micronutrient level treatment for coriander production. Treatment B2 (Azotobacter) was shown to be the optimal biofertilizer level for coriander production. The treatment combination M1B2 (ZnSO4 @ 0.5% x Azotobacter) was shown to be considerably better among all treatment combinations, yielding the highest coriander yield characteristics.

Phosphate-Solubilizing Bacteria: Advances in Their Physiology, Molecular Mechanisms and Microbial Community Effects.

Phosphorus is an essential nutrient for all life on earth and has a major impact on plant growth and crop yield. The forms of phosphorus that can be directly absorbed and utilized by plants are mainly HPO42- and H2PO4-, which are known as usable phosphorus. At present, the total phosphorus content of soils worldwide is 400-1000 mg/kg, of which only 1.00-2.50% is plant-available, which seriously affects the growth of plants and the development of agriculture, resulting in a high level of total phosphorus in soils and a scarcity of available phosphorus. Traditional methods of applying phosphorus fertilizer cannot address phosphorus deficiency problems; they harm the environment and the ore material is a nonrenewable natural resource. Therefore, it is imperative to find alternative environmentally compatible and economically viable strategies to address phosphorus scarcity. Phosphorus-solubilizing bacteria (PSB) can convert insoluble phosphorus in the soil into usable phosphorus that can be directly absorbed by plants, thus improving the uptake and utilization of phosphorus by plants. However, there is no clear and systematic report on the mechanism of action of PSB. Therefore, this paper summarizes the discovery process, species, and distribution of PSB, focusing on the physiological mechanisms outlining the processes of acidolysis, enzymolysis, chelation and complexation reactions of PSB. The related genes regulating PSB acidolysis and enzymatic action as well as genes related to phosphate transport and the molecular direction mechanism of its pathway are examined. The effects of PSB on the structure and abundance of microbial communities in soil are also described, illustrating the mechanism of how PSB interact with microorganisms in soil and indirectly increase the amount of available phosphorus in soil. And three perspectives are considered in further exploring the PSB mechanism in utilizing a synergistic multi-omics approach, exploring PSB-related regulatory genes in different phosphorus levels and investigating the application of PSB as a microbial fungicide. This paper aims to provide theoretical support for improving the utilization of soil insoluble phosphorus and providing optimal management of elemental phosphorus in the future.

Influence of integrated nutrient management on nutrient content (N, P, and K) and nutrient uptake (N, P, and K) of okra (Abelmoschus esculentus (L.) Moench) cv Arka Anamika

The current investigation, designated “Influence of integrated nutrient management on nutrient content (N, P, and K) and nutrient uptake (N, P, and K) of okra (Abelmoschus esculentus (L.) Moench) cv Arka Anamika” took place from July to November 2019 at the College of Horticulture, Rajendranagar, Sri Konda Laxman Telangana State Horticultural University. The trial was employed in Randomized Block Design, with ten treatments replicated three times. The investigation revealed that the administration of 75% RDF + 12.5% RDN through FYM + 12.5% RDN through vermicompost + Azotobacter + Phosphorus solubilizing bacteria (PSB) i.e. T7 substantially boosted the quantities of N, P, and K content in the bhindi pod (2.41, 0.67, and 1.9% correspondingly) and the plant (1.9, 0.24, and 1.3% accordingly). Furthermore, treatment T7 displayed substantially greater overall uptakes of N (63.41 kg/ha), P2O5 (11.38 kg/ha), and K2O (44.92 kg/ha) in comparison with the remaining treatments.

Barley Growth and Phosphorus Uptake in Response to Inoculation with Arbuscular Mycorrhizal Fungi and Phosphorus Solubilizing Bacteria

ABSTRACT Biostimulants and bioinoculants offer the potential to enhance nutrient use efficiency within agricultural cropping systems and thus reduce the amount of mineral fertilizers needed to support crop growth. Considerable uncertainty, however, exists about their efficacy under different management regimes. The present field-based study investigated the effects of phosphorus (P) solubilizing bacteria (PSB) and mycorrhizal (AMF) inoculants in the presence of a range of mineral-based P fertilizers, including triple superphosphate (TSP), struvite and rock phosphate (RP), on the growth, yield, and P uptake of barley (Hordeum vulgare L.). Two consecutive field experiments performed in a low P soil (Eutric Cambisol) revealed that the bioinoculants (PSB and AMF) promoted plant P uptake and grain yield. Moreover, in comparison to P fertilizers lacking bio-inoculants, the application of external P sources combined with bio-inoculants led to significant increases in leaf P concentration, total P uptake, plant dry matter, grain P concentration, and crop yield. Grain yield significantly correlated with P uptake by roots and above-ground parts (i.e. stems, leaves, and spikes) as well as grain P concentration in both seasons. It is concluded that bioinoculants can help improve sustainable P use ultimately leading to greater sustainability of cropping systems and resilience in soil P cycling.