Synergistic effects of biochar/microbial inoculation on the enhancement of pig manure composting

With the aim to comparatively investigate the effect of the addition of additives such as biochar(BC),microbial inoculation(MI)and biochar/microbial inoculation(BCMI)on composting enhancement,nitrogen conservation,greenhouse gas emissions,the quality improvement of pig manure compost were comparatively investigated in a 42-day aerobic pig manure composting experiment.The results showed that the duration of the thermophilic stage,the degradation of organic matter and the detoxification of the compost were enhanced in the BC,MI and BCMI treatments compared with those in the control(without additive).Moreover,the content of total Kjeldahl nitrogen in the BC,MI and BCMI treatments was increased by 38.1,48.9 and 59.0%,respectively,through the reduction of NH_(3) volatilization and N_(2)O production,which were higher than those of the control(31.8%).A reduction in CH_(4) release during composting was not observed with the MI and BCMI treatments.Following 42 days of composting,the final product of the three treatments exhibited acceptable potential for use as a fertilizer in agriculture;the BCMI treatment showed an especially synergistic effect on pig manure composting enhancement.

Improving Acacia auriculiformis seedlings using microbial inoculant(Beneficial Microorganisms)

A microbial inoculant, known as effective microorganisms （EM）, was applied to determine its efficacy on seed germination and seedling growth in the nursery of Acacia auriculiformis A Curm. ex Benth. The seedlings were grown in a mixture of sandy soil and cow dung （3：1） and kept in polybags; EM was poured at different concentra- tions （0.1%, 0.5%, 1%, 2%, 5% and 10%）. Seed germination rate and growth parameters of seedlings - shoot and root lengths, fresh and dry weights of shoots and roots, vigor, volume, and quality indices and stur- diness - were measured. The nodulation status influenced by EM was also observed, along with the measurement ofpigrnent contents in leaves. The highest germination rate （72%） was observed in 2% EM solution while the lowest （55%） was found in control treatment. The highest shoot and root lengths （30.6 cm and 31.2 cm respectively） were recorded in 2% EM and were significantly （p 〈0.05） different from control. Both fresh and dry weights of shoots were maximum （8.66 g and 2.99 g respectively） in 2% EM, whereas both fresh and dry weights of root were maximum （2.56 g and 1.23 g respectively） in 5% EM solution. Although the highest vigor index, volume index, and sturdiness （4450, 628 and 67.5 respec- tively） were found in 2% EM, the highest quality index （0.455） was found in 5% EM solution. The nodule number was higher at a very low （0.5%） concentration of EM but it normally decreased with the increase of concentration. The contents of chlorophyll a, chlorophyll b, and carotenoid were maximum （43.26 mg.L-1, 13.56 mg.L-1 and 17.99 mg.L-1 respectively） in 2% EM. Therefore, low concentration of EM （up to 2%）can be recommended for getting maximum seed germination and seed- ling development ofA. auriculiformis in the nursery.

Effects of Microbial Inoculants on Nutrient Availability and Rice Yield

Under field conditions, an experiment was conducted to study the effects of ammonification bacteria, potassium bacteria and phosphorus bacteria on nutrient availability in soil and yield of rice in the cold region of China and compared to the conventional fertilization. Results showed that DF1P2 treatment （ammonifiers 1.5× 108 cfu· m2, phosphorus bacteria 1.5× 108 cfu. m2, and potassium bacteria 1.5× 108 cfu· m2） increased available nutrient concentrations in soil, increased the concentrations of N, P, and K in plant organs and increased the rice yield and was the most significantly among all the treatments. This treatment could be recommended as the best suitable biological fertilizer application rate for the rice production in the cold region of China.

The Effect of Microbial Inoculants Applied at Ensiling on Sorghum Silage Characteristics and Aerobic Stability

Whole crop forage sorghum (Saccharatum) cultivar FS5 was harvested at the soft dough stage of maturity. The sorghum was chopped to approximately 2 cm pieces and ensiled under laboratory conditions in 1.5 L Weck glass jars. At ensiling, it was treated with two commercial microbial inoculants: inoculant A and inoculant B. The inoculants were applied at 2 × 105 colony forming units g-1 DM. Silage with no additives served as a control. Three jars per treatment were opened on days 2, 4, 8, 15 and 60 post-ensiling to study fermentation dynamics. After 60 days of ensiling, the silages were analyzed and subjected to an aerobic stability test lasting 5 days. Results showed that both inoculants caused a more rapid rate of pH decline and a higher amount of lactic acid production. Silages treated with each inoculant produced a little more CO2 and resulted in more glucose loss as compared with the control. Addition of inoculants did not influence (P > 0.05) the ash and crude protein contents, but tended to decrease the concentration of acetic acid (P < 0.05), butyric acid (P<0.01) and propionic acid (P<0.01), and increase the lactic acid concentration (P<0.01). Silages treated with inoculant A possess the more DM loss, and the higher yeast counts upon aerobic exposure. Silage treated with inoculant B had the most DM (P<0.05), lactic acid contents (P<0.01), the least acetic acid content (P<0.05). Inoculant B reduced the ADF (P<0.01), ADL and NDF (P<0.05) contents. It was concluded that lactic bacteria inoculants may improve the fermentation but might impair the aerobic stability for sorghum ensilage.

Two stages kinetics of municipal solid waste inoculation composting processes

In order to understand the key mechanisms of the composting processes, the municipal solid waste(MSW) composting processes were divided into two stages, and the characteristics of typical experimental scenarios from the viewpoint of microbial kinetics was analyzed. Through experimentation with advanced composting reactor under controlled composting conditions, several equations were worked out to simulate the degradation rate of the substrate. The equations showed that the degradation rate was controlled by concentration of microbes in the first stage. The degradation rates of substrates of inoculation Run A, B, C and Control composting systems were 13 61 g/(kg·h), 13 08 g/(kg·h), 15 671 g/(kg·h), and 10 5 g/(kg·h), respectively. The value of Run C is around 1 5 times higher than that of Control system. The decomposition rate of the second stage is controlled by concentration of substrate. Although the organic matter degradation rates were similar to all Runs, inoculation could reduce the values of the half velocity coefficient K \-m and could be more efficient to make the composting stable. Particularly, for Run C, the degradation rate is high in the first stage, and K \-m is low in the second stage. The results indicated that the inoculation was efficient for the composting processes.

Nursery practice on seed germination and seedling growth of Dalbergia sissoo using beneficial microbial inoculants

Nursery practice using microbial inoculants was performed to find out the efficacy of the inoculants on seed germination and seedling growth of sissoo（Dalbergia sissoo Roxb.）.Microbial inoculants or effective microorganisms（EM） are a mixture of many different beneficial microorganisms in a solution.The seedlings were grown in a mixture of sandy soil and cowdung（3：1） kept in polybags with pouring EM solution at different concentrations（0.1%,0.5%,1%,2%,5% and 10%） before and after a week of sowing the seeds.Seed germination rate and growth parameters of seedlings were measured,such as,shoot and root length,vigor index,fresh and dry weight of shoot and root and total biomass increment.The nodulation status influenced by EM was also observed along with the measurement of pigment contents in leaves.The highest germination rate（69%） was observed in 2% EM treatment,followed by 67% and 65% in 1% and 5% EM.The highest shoot length（33.2 cm） was in 2% EM,whereas highest root length（26.3 cm） was in 1% EM.Both fresh and dry weights from shoot and root,were maximum（4.16 g and 1.57 g;2.12 g and 0.83 g respectively） in 2% EM and were significantly（p ≤ 0.05） different from control.Vigor index was highest（4071） in 2% EM,which was significantly（p ≤ 0.05） different from control.Total dry weight increment was highest in 2% EM treatment,followed by 1% and 5% concentrations of EM.Nodulation number was higher at very low（0.1%） concentration of EM solution but it normally decreased with the increase of EM concentrations.The contents of chlorophyll a,chlorophyll b and carotenoid were highest（60.11,17.05 and 42.48 mg·L1respectively） in 2% EM treatment and lowest（39.35,13.55 and 27.29 mg·L-1 respectively） in control treatment.Therefore,low concentration of EM（up to 2%） can be used for getting maximum seed germination rate and seedling development of Dalbergia sissoo Roxb.

Effects of Microbial Inoculants from Sewage Sludge on Initial Growth of Festuca arundinacea L.

Microbial inoculants were isolated from sewage sludge and applied to turfgrass medium. Effects of microbial inoculants on seed germination and initial growth of Festuca arundinacea L. were analyzed to investigate the optimal proportion of compound microbial inoculants. Significant differences were found in various growth indices and chlorophyll content of F. arundinacea between microbial treatment and control The combination of Pseudomonas stutzeri and Trichoderma reesei exhibited the best results. Compared with the control, seed germination rate, seedling height, shoot dry weight, root weight, chlorophyll a content and chlorophyll b content of F. arundinacea treated with the combination of Pseudomonas stutzeri and Trichoderma reesei were improved by 11.60%, 43.47%, 148%, 159%, 144% and 136%, respectively. Based on comprehensive analysis of various indicators, the optimal proportion （V/V） of microbial combination was Pseudomonas stutzeri： Tfichoderma reesei = 1： 1, which was the most conducive to plant growth and development.

Effects of Low Temperature-tolerant Microbial Inoculants from Municipal Solid Waste Compost on Turf Storage in Winter

Beneficial microorganisms were extracted from municipal solid waste compost and treated under low temperature stress to prepare complex microbial inoc- ulants. Turfgrass was inoculated with the prepared microbial inoculants to investigate the ecological effect of ~crobial inoculants on turf storage in winter. The re- suits showed that complex low temperature tolerant microbial inoculants significandy improved plant height and aboveground biomass of turfgrass. Compared with the non-inoculated control, plant height and biomass of the first batch of inoculated turfgrass were enhanced by 6.47% and 14.32%, respectively; and they were en- hanced by 6.94% and 17.41%, respectively, for the second batch of inoculated turfgrass. Under low temperature stress in winter, the reviving rate of inoculated tarfgrass was significandy higher than that of control, which was improved by 3.34% and 43.33% for the first and second batches of inoculated turfgrass respective- ly. After low temperature storage in winter, inoculated turfgrass revived in advance; specifically, the reviving date of the second batch of inoculated turfgrass was 3 d earlier than that of control. This low temperature tolerant microbial consortium was effective for turfgrass as an ecofriendly and acceptable technology to improve plant performance and development in winter and accelerate time to market of turf.

Research Progress of Application of Microbial Inoculants in Agricultural Production

Microbial inoculants have received increasing attention in strengthening plant biological barriers,antagonizing and inhibiting harmful microorganisms,and ensuring the safe production of agricultural products.This paper summarized the research status of agricultural microbial inoculants,the application of microbial inoculants in agriculture,and the trends and prospects of agricultural microbial research.

Effects of compound microbial inoculant treated wastewater irrigation on soil nutrients and enzyme activities

Wastewater treated by compound microbial inoculant(CMI)in agricultural irrigation can enrich soil fertility and decompose the possible pollutants.In this study,a greenhouse experiment using tomato as the model crop was performed to investigate the effects of treated wastewater irrigation on soil nutrients and enzymes.For this purpose,certain parameters were measured,including soil total nitrogen(N),nitrate N,total phosphorus(P),available potassium(K)and the activities of the enzymes urease,acid phosphatase and catalase in soils irrigated with fresh water,wastewater and CMI-treated wastewater under three amount of irrigation water.The results showed that irrigation with both treated and untreated wastewater significantly increased soil total N,total P,and available K,however the treated wastewater showed higher effects on soil enrichment,especially on available K.The activity of soil urease and acid phosphatase reached highest with treated wastewater irrigation,whereas wastewater irrigation increased the activity of catalase obviously.Soil enzyme and nutrient with fresh water irrigation decreased with increasing water amount;the content of soil urease,nitrate-nitrogen,total N and total P in treated wastewater and wastewater irrigation rose with increasing water amount,but the highest activity of acid phosphatase and the lowest activity of catalase were found in medium irrigation water amount.Under the condition of tomato cultivation,total N,nitrate N and total P were closely correlated with soil urease and catalase;there were significant positive correlation among soil urease,catalase,total N,nitrate N and total P;there existed significantly positive correlation between acid phosphatase and all measured soil nutrient indexes.The results suggested that irrigation with CMI-treated wastewater is a security and effective strategy to agricultural land management.

Actinobacteria-enhanced plant growth, nutrient acquisition, and crop protection:Advances in soil, plant, and microbial multifactorial interactions

Agricultural areas of land are deteriorating every day owing to population increase, rapid urbanization, and industrialization. To feed today’s huge populations, increased crop production is required from smaller areas, which warrants the continuous application of high doses of inorganic fertilizers to agricultural land. These cause damage to soil health and, therefore, nutrient imbalance conditions in arable soils. Under these conditions, the benefits of microbial inoculants (such as Actinobacteria) as replacements for harmful chemicals and promoting ecofriendly sustainable farming practices have been made clear through recent technological advances. There are multifunctional traits involved in the production of different types of bioactive compounds responsible for plant growth promotion, and the biocontrol of phytopathogens has reduced the use of chemical fertilizers and pesticides. There are some well-known groups of nitrogen-fixing Actinobacteria, such as Frankia, which undergo mutualism with plants and offer enhanced symbiotic trade-offs.In addition to nitrogen fixation, increasing availability of major plant nutrients in soil due to the solubilization of immobilized forms of phosphorus and potassium compounds, production of phytohormones, such as indole-3-acetic acid, indole-3-pyruvic acid, gibberellins, and cytokinins, improving organic matter decomposition by releasing cellulases, xylanase, glucanases, lipases, and proteases, and suppression of soil-borne pathogens by the production of siderophores, ammonia, hydrogen cyanide, and chitinase are important features of Actinobacteria useful for combating biotic and abiotic stresses in plants.The positive influence of Actinobacteria on soil fertility and plant health has motivated us to compile this review of important findings associated with sustaining plant productivity in the long run.

Microbial inoculants and garbage fermentation liquid reduced root-knot nematode disease and As uptake in Panax quinquefolium cultivation by modulating rhizosphere microbiota community

Objective:To find a suitable ecological cultivation measure to solve the problem of root-knot nematode disease of Panax quinquefolium(Panacis Quinquefolii Radix)and the heavy metals accumulating in its roots.Methods:Three-year-old P.quinquefolium was treated with four different combinations of microbial inoculant(MI)and garbage fermentation liquid(GFL)[the joint application of‘TuXiu’MI and Fifty potassium MI(TF),the combination use of‘No.1'MI and Fifty potassium MI(NF),‘Gulefeng’poly-γ-glutamic acid MI(PGA),GFL],and the untreated control(CK).Here,high-throughput sequencing,ICP-MS and UPLC were employed to systematically characterize changes of microbial diversity and structure composition,heavy metals(As,Cd and Pb)content and ginsenoside content among different treatments.Results:The results revealed that different MIs and GFL could increase the root dry weight of P.quinquefolium,PGA enhanced it by 83.24%,followed by GFL(49.93%),meanwhile,PGA and GFL were able to lessen root-knot nematode disease incidence by 57.25%and 64.35%.The treatment of PGA and GFL can also effectively reduce heavy metals in roots.The As content in GFL and PGA was decreased by 52.17%and 43.48%respectively,while the Cd and Pb contents of GFL and PGA was decreased somewhat.Additionally,the content of total ginsenosides was increased by 42.14%and 42.07%,in response to TF and NF,respectively.Our metagenomic analysis showed that the relative abundance of particular soil microbial community members related to the biocontrol of root-knot nematode disease and plant pathogen(i.e.,Chaetomium in NF,Xylari in GFL,and Microascus in PGA),heavy metal bioremediation(Hyphomacrobium in PGA and Xylaria in GFL),and nitrogen fixation(Nordella and Nitrospira in TF)was significantly increased;notably,potential harmful microflora,such as Plectosaphaerella and Rhizobacter,were more abundant in the control group.Conclusion:MI and GFL could improve the quality of P.quinquefolium by modifying its rhizosphere microbial community structure and composition,both of them are beneficial to the development of ecological cultivation of P.quinquefolium.

Effects of rumen microorganisms on the decomposition of recycled straw residue

Recently,returning straw to the fields has been proved as a direct and effective method to tackle soil nutrient loss and agricultural pollution.Meanwhile,the slow decomposition of straw may harm the growth of the next crop.This study aimed to determine the effects of rumen microorganisms(RMs)on straw decomposition,bacterial microbial community structure,soil properties,and soil enzyme activity.The results showed that RMs significantly enhanced the degradation rate of straw in the soil,reaching 39.52%,which was 41.37%higher than that of the control on the 30th day after straw return.After 30 d,straw degradation showed a significant slower trend in both the control and the experimental groups.According to the soil physicochemical parameters,the application of rumen fluid expedited soil matter transformation and nutrient buildup,and increased the urease,sucrase,and cellulase activity by 10%‒20%.The qualitative analysis of straw showed that the hydroxyl functional group structure of cellulose in straw was greatly damaged after the application of rumen fluid.The analysis of soil microbial community structure revealed that the addition of rumen fluid led to the proliferation of Actinobacteria with strong cellulose degradation ability,which was the main reason for the accelerated straw decomposition.Our study highlights that returning rice straw to the fields with rumen fluid inoculation can be used as an effective measure to enhance the biological value of recycled rice straw,proposing a viable solution to the problem of sluggish straw decomposition.

Effects of background fertilization followed by co-application of two kinds of bacteria on soil nutrient content and rice yield in Northeast China

With the improvement of living standards,people pay more and more attention to the quality and safety of rice.Microbial agents are favored by the public because they can activate the nutrient supply in the soil,and reduce the residue and application amount of chemical fertilizers and pesticides.Based on the conventional fertilization in the field,Bacillus mucilaginosus and Aspergillus niger were applied,Bacillus mucilaginosus was inoculated at four levels in the paddy soil in the cold region of Heilongjiang Province of China.The effects of different proportions of Bacillus mucilaginosus and Aspergillus niger on the number of soil microorganisms,enzyme activity,microbial biomass,soil biochemical intensity,soil nutrient content,plant nutrient content and yield were studied,and the effects on the plant nutrient content of rice and the nutrient dynamics were discussed.The results showed that a 2.62%-21.20%higher yield of rice obtained from co-application treatments compared with that of the control-blank treatment.Furthermore,the highest yield obtained(10736±65 kg/hm^(2))suggested that the optimized values for the two bacteria applied were 120×10^(11) CFU/hm^(2) for Bacillus mucilaginosus and 15×10^(11) CFU/hm^(2) for Aspergillus niger.Bacillus mucilaginosus can decompose minerals in soil,dissolve potassium and silicon,decompose apatite and release phosphorus into soil.Aspergillus niger can transform the phosphate which cannot be absorbed by plants into soluble phosphate which can be directly absorbed by plants by producing non-volatile acids.In particular,Bacillus mucilaginosus and Aspergillus niger have synergistic effect,and their combined application effect is greater than that of two bacteria alone.Co-application promoted the release of soil soluble silicon,and then increased the silicon content of plants.At the same time,soil microorganism,microbial biomass,enzyme activity and biochemical activity all increased significantly.This study provides an effective way to reduce the amount of chemical fertilizer applied in rice production in cold regions of China.