Biological Fertilizers Research Articles

Isolation and identification of mycorrhizal helper bacteria of Vaccinium uliginosum and their interaction with mycorrhizal fungi.

Mycorrhizal helper bacteria (MHB) can promote mycorrhizal fungal colonization and form mycorrhizal symbiosis structures. To investigate the effect of interactions between mycorrhizal beneficial microorganisms on the growth of blueberry, 45 strains of bacteria isolated from the rhizosphere soil of Vaccinium uliginosum were screened for potential MHB strains using the dry-plate confrontation assay and the bacterial extracellular metabolite promotion method. The results showed that the growth rate of mycelium of Oidiodendron maius 143, an ericoid mycorrhizal fungal strain, was increased by 33.33 and 77.77% for bacterial strains L6 and LM3, respectively, compared with the control in the dry-plate confrontation assay. In addition, the extracellular metabolites of L6 and LM3 significantly promoted the growth of O. maius 143 mycelium with an average growth rate of 40.9 and 57.1%, respectively, the cell wall-degrading enzyme activities and genes of O. maius 143 was significantly increased. Therefore, L6 and LM3 were preliminarily identified as potential MHB strains. In addition, the co-inoculated treatments significantly increased blueberry growth; increased the nitrate reductase, glutamate dehydrogenase, glutamine synthetase, and glutamate synthase activities in the leaves; and promoted nutrient uptake in blueberry. Based on the physiological, and 16S rDNA gene molecular analyses, we initially identified strain L6 as Paenarthrobacter nicotinovorans and LM3 as Bacillus circulans. Metabolomic analysis revealed that mycelial exudates contain large amounts of sugars, organic acids and amino acids, which can be used as substrates to stimulate the growth of MHB. In conclusion, L6 and LM3 and O. maius 143 promote each other's growth, while co-inoculation of L6 and LM3 with O. maius 143 can promote the growth of blueberry seedlings, providing a theoretical basis for further studies on the mechanism of ericoid mycorrhizal fungi-MHB-blueberry interactions. It laid the technical foundation for the exploitation of biocontrol strain resources and the development of biological fertilizer.

Growth response of not-ready-to-distribute tea (Camellia sinensis (L) o. Kuntze) seedlings due to application of biofertilizer at various concentrations and intervals

The plantation rejuvenation program makes the need for ready-to-distribute tea seedlings getting higher. Meanwhile, the nursery's seedlings are mostly not ready to distribute. This study aimed to determine the response of not-ready-distribute tea seedlings due to the application of biofertilizers at various concentrations and intervals. This experiment was carried out at Gambung Tea and Quinine Research Center Nursery, conducted from December 2021 to February 2022 at an altitude of 1,350 meters above sea level (asl). The experimental method used was a randomized block design with eight treatment combinations, namely: control (no fertilizer); urea fertilizer every two weeks; Biofertilizer 5 mL L-1 + interval once a week; Biofertilizer 5 mL L-1 + interval every two weeks; Biofertilizer 10 mL L-1 + break once a week; Biofertilizer 10 mL L-1 + interval every two weeks; Biofertilizer 15 mL L-1 + interval once a week; Biofertilizer 15 mL L-1 + interval every two weeks, all repeated four times. The experimental results showed that treatment of biological fertilizers influenced the parameter number of leaves and chlorophyll index. The application of biofertilizer with a concentration of 15 mL L-1 + interval of 2 weeks greatly influenced the parameters of leaf number and chlorophyll content index.

Effects of Soaking Rice Seeds with Biofertilizers on Brown Spot Disease Drechslera oryzae and Sprout Growth.

Rice (Oryza sativa L.) is a staple food crop for the majority of the population in Indonesia. In rice cultivation, brown spot disease is often damaged by the fungus Drechslera oryzae. This study aims to examine the effect of applying biofertilizers on brown spot disease and growth of rice sprouts. The treatments tried were Bion-up, KIBRT, Azoto-Tricho, biofertilizers and propineb fungicide as a comparison. The experimental design used a completely randomized design with four replications. The observed variables were disease intensity, shoot height, root length, and fresh weight of sprouts. The results showed that the application of biological fertilizers Bion up, KIBRT and Azoto-Tricho was effective in controlling brown spot disease and increasing growth in shoot height, root length and sprout fresh weight.

An Exploratory Research on the Adoption of Different Phosphate-Solubilizing Fungi for Production of Phosphate Biofertilizers

Using the inherent capacity of the soil to meet the nutritional needs of plants is considered an efficient and environmentally friendly solution. In order to study the survival of different phosphate-solubilizing fungi in different combinations of rock phosphate and organic matter as the basis of biofertilizer with the aim of producing an effective formula of biological phosphorus granular fertilizer, this study was conducted as a factorial experiment based on a completely randomized design with three replications. For this purpose, after isolating phosphate-solubilizing fungal strains from agricultural soils in different regions of Iran (Fars, Kermanshah and Razavi Khorasan provinces), the superior strains with high growth stimulating capability were selected for bio-fertilizer formulation based on determination of fungi survival. In order to study the survival of the superior strains [including Talaromyces pinophilus strain 1FB, T. pinophilus strain MFA, Talaromyces verruculosus strain PF157-2 and Aspergillus tubingensis strain PF140-2], six levels of carrier including 100% rock phosphate, 80% rock phosphate + 20% organic matter, 60% rock phosphate + organic matter 40%, 40% rock phosphate + 60% organic matter, 20% rock phosphate + 80% organic matter and 10% rock phosphate + 90% organic matter were used in three temperature levels (28, 40 and 50 °C) during eight time periods (15 days, 30 days, 45 days, 60 days, 75 days, 90 days, 105 days and 120 days) under incubation condition. The results showed that based on the longer time of survival, and the instruction of Soil and Water Research Institute, Karaj, Iran, for the minimum acceptable number of phosphate solubilizing fungi in granulated phosphate microbial fertilizer, a granulated phosphate microbial fertilizer included each of the isolates (respectively PF 157-2 > PF 140-2 > MFA≫ 1FB), a carrier with at least 20% rock phosphate + at least 20% organic matter, and at the temperature of 28 or 40 °C may be developed and recommended in the agricultural soils as an environment-friendly source of phosphorus.

Comparative Study of the Effect of Biological and Chemical Fertilization on some Growth Characteristics of Wheat Crop Triticum aestivum L.

A study was conducted to find out the effect of biological and chemical fertilization and the interaction between them on the growth and yield of wheat, a field experiment was conducted in one of the fields affiliated with Babylon Governorate during the season 2021-2022 and in soil with a clay mixture texture. The second is fertilization, The biological (comparative) and symbolized by the symbols (B0, B1 and B2), and the second factor is chemical fertilization at an amount of 20:20:20 and 200 kg H-1 in whole and half of the recommendation, and at three levels (0, 150 and 300) kg H-1 It was denoted by the symbols (0, C1 and C2) sequentially, thus the number of transactions became nine transactions, with three repetitions to become the number of experimental units is 27 experimental units. The experiment was carried out according to the design of complete randomized interrupters (R.C.B.D), and 99 seeds of wheat were planted on 11/18/2021. After maturity, the height of the plant, chlorophyll, the area of the flag leaf and the weight of a thousand grains, the treatment of adding biofertilization b1 lost and gave the highest values of growth indicators outperform biological fertilization of wheat seeds was significant for treatment B1, and it gave the highest growth of wheat crop from plant height of 108.47 cm, number of branches 7.33 branches, area of flag leaf 51.73 cm2 and chlorophyll index 49.36 SPAD UNIT Ton h-1.

Effect of Nitrogenous, Organic and Biological Fertilizers on some Vegetative and Qualitative Characteristics of Spinach Plant Spinacea oleracea L.

The experiment was conducted in the fields of the Department of Horticulture and Landscape / College of Agriculture / University of Karbala in Al-Hussainiya district of Karbala governorate during the autumn season 2021-2022 to study the response of some chemical and qualitative characteristics of spinach variety Viroflay, with 2 factors, the levels of nitrogen fertilizer (urea) represent the main plots and the sub plots the fertilization treatments of the secondary panels (Sub plot) and the experiment included 54 experimental units, and the differences were compared using the least significant difference test (L.S.D) at a probability level of 0.05. The results of the fertilizer addition (biological fertilizer + poultry manure) to the T6 treatment showed a significant superiority in the characteristics of vegetative growth, as it gave the highest rates and reached in plant height (23.71 cm. plant -1) And the average number of leaves (11.77 leaves. Plant-1) and the dry weight of the shoot (8.97 g. plant-1). The addition of nitrogen fertilizer (urea) when treated with N100% resulted in a significant superiority in the characteristics of vegetative growth, and the highest rates were in plant height (22.71 cm. Plant- 1) And the average number of leaves (10.89 leaves. Plant-1), and the dry weight of the shoot (10.23 g. plant-1), The same treatment had a significant effect on the chemical indicators, as it recorded a clear decrease in the content of nitrates and oxalates, which amounted to (110.0 mg g-1 and 81.20 mg g.100 ml) Plant respectively.

The effectiveness of beyonic startmix organic biological fertilizer on growth and yield of Inpari rice 30

Increasing agricultural production, especially rice, uses a lot of chemical fertilizers, which can have a negative effect on the environment. The solution sought to overcome the impact of using chemical fertilizers is using biological organic fertilizer (POH) beyonic startmix, which contains microorganisms that provide plant nutrients, produce growth hormones, and protect plants from pests and diseases. The study aimed to determine the effect of startmix beyonic organic fertilizer on the growth and yield of inpari 30 rice. The study was carried out in the Motekar farmer group’s paddy fields in Jabong Village, Pagaden District, Subang Regency. The study lasted four months, starting from January to April 2018. The study used a field experiment method using a Randomized Block Design (RBD) pattern, which consisted of 2 treatments, namely with fertilization and without fertilization with startmix beyonic biological organic fertilizer, each carried out on three plots with five replicates. Parameters observed included plant height, number of tillers, number of panicles, number of grains per panicle, the weight of 1000 dry grain seeds, and grain yield. The results showed that applying POH significantly affected the number of tillers, panicles, and paddy yields. The yield of dry milled grain with POH was, on average, 7.463 tons/ha, 16.91% higher than without POH fertilization at 6.201 tons/ha on average.

Effect of T. harzianum and G. mosseae Biological Inoculation and Phosphate Rocks on the Availability of NPK in the Rhizosphere of Barley Crop (Hordium Valgari L.)

When it comes to increasing crop yields, biological fertilizers are crucial. So, researchers looked into how different concentrations of phosphate rock and T. harzianum and G. mosseae fungal fertilizers affected NPK availability in the rhizosphere of a barley crop. In the fall of 2021, farmers in the Al-Qadisiyah Governorate tested out a new barley variety they’d come up with, calling it “Samir 1,” on clay loamy soil. A randomized complete block design (RCBD) with three replicates was used to create the factorial experiment. The experiment used four different doses of phosphate rock (P0, P1, P2, and P3) at concentrations of (0,1000,1500, and 2000) t/ha-1, as well as two doses of T. harzianum inoculum (T0, control; T1, fungal inoculation); and two doses of G. mosseae inoculum (G0, control; G1, fungal inoculation). According to the findings, nitrogen, phosphate, and potassium (NPK) availability in the soil were significantly increased by 41.32, 16.54, and 225.43 mg/kg/soil-1 in the interaction treatment compared to the control.

The effect of limestone dust and different doses of mycorrhizal biological fertilizer on the growth of coffee seedlings in former quarry limestone mines

Reclamation (revegetation) activities must be carried out upon the completion of mining. Limestone dust can affect the physical, chemical, and biological properties of soil. To increase the growth rate of non-wood product species such as coffee, biological fertilizers of mycorrhiza are introduced to the reclamation site. The goal of this study is to examine the effects of limestone dust covering former mines and different doses of mycorrhizal biological fertilizers on the growth of coffee seedlings. The research was conducted using the Randomized Complete Block Design method. Research areas were divided into groups/blocks consisting of soil without limestone dust, dust-covered 0-2.5 cm, and dust-covered 0-5 cm. The groups were treated with the addition of 10 g, 15 g and 20 g mycorrhizal biological fertilizers with five replications each. NPK inorganic fertilizer was given every one month to all treatments. The parameters observed from the growth of coffee seedlings were plant height, Stem diameter, and number of leaves. Based on the results, limestone dust influenced soil conditions such as silt, clay, pH, organic C, bulk density, and C/N ratio. In addition, limestone dust affected the plant height and number of leaves of coffee seedlings compared to those grown in an area without dust. Differences in the amount of mycorrhizal biologic fertilizers were significant (p<0.05) and tended to increase for the parameters of height and diameter of coffee seedlings. However, the difference in the dose of mycorrhizal biological fertilizers has been shown to significantly (p<0.05) decrease the number of leaves.

Potency of entomopathogen Beauveria bassiana fungus as biofertilizer and biostimulant to increase the plant growth of Cayenne pepper (Capsicum frutescens L.)

This research aimed to determine the Beauveria bassiana entomopathogen fungus as a biofertilizer and biostimulant. The research was conducted at the Biological Control laboratory and Wire House, Universitas Andalas. The potency of B. bassiana produced the IAA hormone was carried out by a This was qualitative research by observing a pink color change in the Salkowsky solution while the potency of B. bassiana to dissolve phosphate by using Pikovskaya medium. The test results on Pikovskaya media showed that all tested isolates had the potential to dissolve phosphate at 7, 10, and 14 days. The largest clear zone area was in the 14 days, found in Bb WS isolates (5.42 mm) followed by TD312 isolates (5.28mm). To test of plant growth in the laboratory was carried out by testing the germination of seeds by blotter test and test on paper. The design used was a non-factorial Completely Randomized. The results showed that the highest percentage of germination was found in TD312 and BbWS isolates. The potency of B. bassiana isolates as growth promoters can be seen from an increase in plant height and the number of chili leaves. All of the results indicated that entomopathogen fungus can be applied as biological fertilizers and biostimulants on cayenne pepper plants.

Application of Liquid Organic Pusri Fertilizer (LOPF) and Inorganic Fertilizer on Ultisols Planted With Red Chili (Capsicum annuum L.)

Red chili is a strategic horticultural commodity that is currently experiencing an increase in demand, especially in the food industry. Chili productivity itself tends to be unstable and often decreases. The things that can be done to increase the plant growth and production are fertilization. Liquid Organic Pusri Fertilizer (LOPF) is a biological fertilizer product developed by Pupuk Sriwidjaja Ltd. As the growth promoter, LOPF contains nitrogen fixing bacteria, P and K solubillizing bacteria with a biostimulant carrier made from seaweed extract. This study was designed in a randomized block design with 9 treatment levels and 3 replications. The treatment levels are P0 (100% inorganic fertilizer); P1 (LOPF application to soil); P2 (LOPF application to soil + 50% inorganic fertilizer); P3 (LOPF application to soil + 75% inorganic fertilizer); P4 (LOPF application to soil + 100% inorganic fertilizer); P5 (LOPF application to seeds and soil); P6 (LOPF application to seeds and soil + 50% inorganic fertilizer); P7 (LOPF application to seeds and soil + 75% inorganic fertilizer); and P8 (LOPF application to seeds and soil + 100% inorganic fertilizer). The recommendation dose of 100% inorganic fertilizer for NPK 16-16-16 is 300 kg ha−1 and urea fertilizer 200 kg ha−1. LOPF applied to seeds with a concentration of 100 ppm and in soil was 12 L ha−1. Application of LOPF on seeds and soil combined with 100% recommendation dose of inorganic fertilizer gave the best results in increasing the production of red chili plants with a production of 9.70 tons ha−1.

Use of Trichoderma as an Effort to Increase Growth and Productivity of Maize Plants

Climate change is one of the obstacles that must be faced in agricultural development because it impacts decreasing soil fertility and agricultural productivity. Therefore, efforts are needed to maintain and even increase productivity, one of which is utilizing microorganisms that function as biological fertilizers to keep the soil environment and support the expected results. This study aims to examine the potential of Trichoderma in increasing the growth and productivity of maize plants. This research was conducted using the Randomized Block Design method, nine treatments (A= Control, B= standard NPK, C=¼ NPK + 1 PT, D=½ NPK + 1 PT, E=¾ NPK +1 PT, F= 1 NPK + 1 PT, G=¾ NPK + PT, H=¾ NPK + PT, I=¾ NPK + PT) with three replications, so there were 27 experimental plots. The results showed that using Trichoderma accompanied by NPK fertilizer affected increasing plant growth (plant height, number of leaves, and stem diameter) and maize plants. The use of Trichoderma at various doses can increase the productivity of maize plants.

Soil characteristics controlling nitrous oxide emissions of tropical peatlands

Emission of nitrous oxide (N2O) from peatlands contributes very significantly to the world global warming, although the factors controlling N2O emissions from peatlands are not yet clear. This study aimed to determine peat characteristics controlling N2O emissions in peatlands. N2O emissions and several soil characteristics (pH, electrical conductivity, height of water table, water-filled pore space, decomposition degree of peats, bulk density, organic carbon, total nitrogen, and concentrations of ammonium and nitrate) were observed in peatlands with different crops and land-uses: lettuce, spring-onion, albizia, shrubs-peat, and burned-peats. Correlation-regression analyses were employed to quantify peat properties influencing the rates of N2O emission from peatlands. The results of the study showed that N2O emissions varied based on the type of crops/land-uses, in which peats used for crop cultivation had higher N2O emissions than others. The results of the analysis also revealed that N2O emissions of peat were controlled by variables related to water contents and the contents of NH4 + and NO3 −. In peats with relatively similar NH4 + and NO3 − contents, N2O emissions were determined by variables related to water contents (height of water table and volumetric water contents). The result of this study shows the need for water and peat fertility management for the mitigation of N2O emission from peatlands. Thus, managing the availability of nitrogen by using biological fertilizers to reduce the amounts of inorganic nitrogen fertilizers is required to reduce N2O emissions without decreasing crop yields in peatlands.

Teknik Aplikasi Pupuk Hayati (Been Sae) Pada Tanaman Padi di BPP Meureubo

This community service activity was carried out with the aim of providing information to farmer groups regarding the benefits and uses as well as the application of Been Sae biofertilizer. In addition, other objectives are also one of the Tridharma activities for the writer. The stages of implementing this community service activity are a form of counseling about the technical application of Been Sae's biological fertilizer to rice plants (Oriza Sateva, L). to improve the physical, chemical and biological properties of the soil in order to increase crop production and maintain the binding capacity of groundwater to nutrients while at the same time suppressing disturbing elements. This community service activity was carried out at the Farmer Group in the village of Mesjid Tuha Meurebo District. The exact time and method of fertilization must be known, including: The rules for using Been Sae fertilizer are by dissolving 10 ml of Been sae in 1 liter of water, stirring thoroughly, then placing it in a tube (spray tank/sprayer), spraying it on the soil or roots. For Hatchery; the seeds are soaked with Been sae solution as much as 3 ml/liter of water for 30 minutes, then aired to dry, after drying the seeds can be planted. Maintenance is carried out by spraying Been sae a week after planting with a dose of 2 liters/200 liters of water/Ha of soil, then spraying the plants and soil every 2/week, Beensae can be used as a decomposer mixture in making compost. The conclusion from this activity is that farmers know more about the benefits and uses of Been Sae biofertilizer.

Alfisol Soil Fertility Before Planting and After Harvest as Meloon Planting Media with Bioboost Fertilization

Soil fertility is important in the cultivation process. Soil fertility is the potential of the soil to provide nutrients in sufficient quantities in available and balanced forms to ensure optimum plant growth and production. The current availability of nutrients in the soil has decreased as a result of continuous land use with the use of chemical fertilizers in the cultivation process, plus leaching and erosion by rainwater, not least in Alfisol soils. Therefore, fertilization with organic materials is carried out, namely the provision of Bioboost fertilizer. Bio boost is a biological fertilizer containing superior soil microorganisms, useful for increasing soil fertility as a result of soil biochemical processes. One of the applications of organic cultivation is the cultivation of melon (Cucumis melo L.) because melon is a plant that has high economic value and is profitable to be cultivated as a source of income for farmers. Based on this, a study was conducted to determine the nutrient status of Alfisol soil before planting and after harvesting which was used as a Melon plant with various concentrations of Bioobost fertilization. Furthermore, for the analysis of soil fertility, laboratory analysis was carried out by taking 1 kg of disturbed soil samples that had been air-dried and then analyzing soil properties, namely texture, pH (H2O), C-Organic (%), Nitrogen (%), P2O5 (ppm), K (cmol kg-1), Ca (cmol kg-1), Mg (cmol kg-1), Na (cmol kg-1), Na (cmol kg-1), CEC (cmol kg-1), and KB (%). The application of Bio boosts fertilizer showed an increase in the nutrient status of Alfisol soil as a Melon growing from low to moderate categories before planting to medium to high categories after harvest. The more concentration of Bioboost fertilizer given, the soil nutrient status also increases. The concentration of P4 (1100ml bio boost + 400ml water) gave the highest increase in nutrient status.
 Keywords: bioboost; soil-fertility; melon

Pertumbuhan Dan Produksi Tanaman Sawi Melalui Aplikasi Pupuk Organik Lumpur Laut Dengan Pupuk Kandang

The growth of mustard plants is influenced by the availability of nutrients through the application of fertilizers. Manure and sea mud are one type of biological fertilizer. The study aims to determine the optimal dose of sea mud and manure for the growth and production of mustard plants. The study design was a randomized group design consisting of 2 factors and repeated 3 times. The first of Sea Mud treatment (L) consists of levels, namely: L0 = Control; L1=500 g, L2= 750 g. L3 1000 g. The second factor is that the dose of manure consists of levels, namely: P0=without manure; P1=120 g, P2=160 g: and P3 = 200g. The results showed that L3 treatment was able to increase plant height, while the number of leaves was best in L2 treatment. This treatment was also able to increase the number of leaves, fresh weight and dry weight but between L2 and L3 treatments did not differ markedly. P3 manure treatment is able to increase the best number of leaves, while fresh weight is best P2 treatment. The interaction between treatments only occurred in plant height and leaf area parameters at 17 HST observations.

Mediating Effect of Bio-Organic Fertilizer on the Physiological Characteristics of “Qi-Nan” Agarwood from Aquilaria sinensis (Lour.)

This study examines the impact of bio-organic fertilizers on the physiological characteristics and leaf nutrient content of “Qi-Nan” agarwood seedlings. The aim is to provide a theoretical foundation for the efficient cultivation of “Qi-Nan”. The experiment was conducted under field conditions using a Randomized complete block design. The control group received no fertilization, while the three fertilizer-treated groups received vermicompost, sheep manure, or microbial organic fertilizer. The results indicate that the application of bio-organic fertilizer significantly promoted the growth of plant height and diameter, increased the contents of soluble proteins, soluble sugar, chlorophyll, and leaf nutrients; and decreased the contents of free proline, peroxidase, malondialdehyde, and other stress indices. Redundancy analysis showed that the main factors affecting the seedlings height and diameter were free proline, chlorophyll, total nitrogen, and total potassium. Principal component analysis and membership function analysis revealed significant variations in growth, physiological characteristics, and nutrient content among the three fertilizer groups and the control group, with vermicompost > microbial organic fertilizer > sheep manure > no fertilization. In conclusion, biological organic fertilizer significantly promotes the growth of “Qi-Nan” seedlings, and vermicompost is the most effective fertilizer in this experiment.

Identification and characterization of siderophilic biocontrol strain SL-44 combined with whole genome

Using rhizobacteria as biological fertilizer is gradually expanding in agriculture as excellent substitutes for chemical fertilizers. Bacillus subtilis SL-44 is a plant growth-promoting rhizobacteria screened from the severely salinized cotton rhizosphere soil in Xinjiang. Study showed that indole-3-acetic acid, organic acid production, nitrogen fixation, and other beneficial secondary metabolite secretion can be synthesized by stain SL-44. At the same time, fencyclin, lipopeptide, chitinase, and other antifungal substances were also detected from the secretion of Bacillus subtilis SL-44, which can effectively control plant diseases. Siderophore separated from SL-44 was verified by HPLC, and results showed it was likely bacillibactin. This study also verified that SL-44 has high antifungal activity against Rhizoctonia solani through in vitro antifungal experiments. The B. subtilis SL-44 whole genome was sequenced and annotated to further explore the biotechnological potential of SL-44. Anda large number of genes involved in the synthesis of anti-oxidative stress, antibiotic, and toxins were found. Genome-wide analysis provides clear evidence to support the great potential of B. subtilis SL-44 strain to produce multiple bioantagonistic natural products and growth-promoting metabolites, which may facilitate further research into effective therapies for harmful diseases.

Different changes of bacterial diversity and soil metabolites in tea plants-legume intercropping systems.

As an essential agroforestry, intercropping legumes can improve the physical, chemical, and biological fertility of the soil in tea plantations. However, the effects of intercropping different legume species on soil properties, bacterial communities, and metabolites remain elusive. In this study, the 0-20cm and 20-40cm soils of three planting patterns (T1: tea plants/mung bean intercropping, T2: tea plants/adzuki bean intercropping, T3: tea plants/mung bean and adzuki bean intercropping) were sampled to explore the diversity of the bacterial community and soil metabolites. The findings showed that, as compared to monocropping, intercropping systems had greater concentrations of organic matter (OM) and dissolved organic carbon (DOC). Notably, pH values were significantly lower, and soil nutrients increased in intercropping systems compared with monoculture in 20-40cm soils, especially in T3. In addition, intercropping resulted in an increased relative abundance of Proteobacteria but a decreased relative abundance of Actinobacteria. 4-methyl-Tetradecane, acetamide, and diethyl carbamic acid were key metabolites mediating the root-microbe interactions, especially in tea plants/adzuki intercropping and tea plants/mung bean, adzuki bean mixed intercropping soils. Co-occurrence network analysis showed that arabinofuranose, abundant in tea plants and adzuki bean intercropping soils, showed the most remarkable correlation with the soil bacterial taxa. Our findings demonstrate that intercropping with adzuki beans is better at enhancing the diversity of soil bacteria and soil metabolites and is more weed-suppressing than other tea plants/legume intercropping systems.

Seed treatments with salicylic acid and Azospirillum brasilense enhance growth and yield of maize plants (Zea mays L.) under field conditions

Salicylic acid and Azospirillum brasilense stimulate plant growth and productivity. In some environments, plant physiology similarly responds to both bioactive products. Considering this, a field experiment was conducted to study the physiological effect of Salicilic acid and A. brasilense on growth and grain yield of maize plants. The experiment involved three treatments consisting of imbibed seeds in an aqueous solution of SA (0.01 mM), inoculated seeds with A. brasilense and a control treatment. Seed imbibition in SA and inoculation with A. brasilense improved vegetative growth in the early stages of crop ontogeny, increasing leaf growth, plant height, stem diameter and biomass accumulation. Spikelet length and weight were greater in plants first inoculated with A. brasilense and then treated with SA. Results indicated that SA stimulated biomass partitioning towards leaves, root and stem, while A. brasilense mainly affected leaf growth, plant height, ear dimensions and grain yield. Such results turn crucial for biological fertilization strategies aimed at reducing pollutant loads that accompany chemical fertilizers. Both products can be part of maize management practices given competitive economic advantages and sustainability. Highlights: Seed imbibition in SA and inoculation with brasilense improved vegetative growth in the early stages of crop ontogeny, increasing leaf growth, plant height, stem diameter and biomass accumulation. Salicylic Acid stimulated biomass partitioning towards leaves, root and stem in maize plants. Azospirillum brasilense stimulates leaf growth, plant height, as well as ear dimensions and grain yield in corn plants.