Assessment of Soil Health Indicators Under the Influence of Nanocompounds and Bacillus spp. in Field Condition

Agricultural yield of major crops is low due to the injudicious use of chemical fertilizers that affects soil fertility and biodiversity severely and thereby affecting plant growth. Soil health is regulated by various factors such as physicochemical properties of the soil, availability of micro/macronutrients, soil health indicator enzymes and microbial diversity which are essential for agriculture productivity. Thus, it is required to draw attention towards an eco-friendly approach that protects the beneficial microbial population of soil. Application of different bioinoculants and agriusable nanocompounds has been reported to enhance soil quality with increased nutrient status and beneficial bacterial population, but additive effects of combined treatments on soil microbial population are largely unknown. The present study investigated the impact of nanozeolite and nanochitosan along with two Bacillus spp. on rhizospheric microbial flora and indicator enzymes to signify soil health under field conditions on maize. Soil health was ascertained by evaluating physicochemical analysis; total bacterial counts including N, P, and K solubilizing bacteria; and soil health indicator enzymes like fluorescein diacetate hydrolysis, alkaline phosphatase, β-glucosidase, dehydrogenase, amylase, and arylesterase. Change in copy number of 16S rRNA as a marker gene was used to quantify the bacterial population using quantitative PCR (qPCR) in different treatments. Our study revealed that nanocompounds with Bacillus spp. significantly (p < 0.05) enhanced total microbial count (16.89%), NPK solubilizing bacteria (46%, 41.37%, and 57.14%), and the level of soil health indicator enzymes up to twofold over control after 20, 40, and 60 days of the experiment. qPCR analysis showed a higher copy number of the 16S rRNA gene in treated samples, which also indicates a positive impact on soil bacterial population. This study presents a valuable approach to improve soil quality in combined treatments of nanocompounds and bioinoculants which can be used as a good alternative to chemical fertilizers for sustainable agriculture.

Silicon substances for restoration of oil-contaminated areas

Numerous investigations demonstrate that active forms of silicon (Si) enhance the plant tolerance against abiotic stresses by several mechanisms, including increasing the antioxidant activities and minimizing oxidative damage. Soil contamination with oil and oil products relates to abiotic stress that detrimentally affects soil microbial population and plant growth. Considering the crucial role of microorganisms and plants in bioremediation of oil-polluted areas, Si substances can be beneficial to acceleration of soil reclamation. In greenhouse experiment, wheat was grown in Grey Forest Soil contaminated with used motor oil. The effect of fumed silica and monosilicic acid on soil enzymatic activity and plant growth was studied. Both Si substances provided increasing the plant biomass and the activities of catalase and dehydrogenase. As regards the plant growth, the effect of Si was more pronounced in polluted soil, while the enzyme activity was higher affected in unpolluted soil. The activities of catalase and dehydrogenase were closely correlated to the water-soluble Si in soil (R=0.91-0.92). Silicon substances with high content of, plant-and microorganism-available Si might be promising for involvement in bioremediation technology for oil-contaminated soil.

Diversity Analysis of Soil Microbial Population Abundance Before and After Planting JunCao "Oasis No. 1" in Saline-Alkali Soil

In order to explore the difference of soil microbial population structure and abundance before and after planting JunCao"Oasis No. 1" in saline-alkali soil, verify the improvement effect of JunCao"Oasis No. 1" on microbial population structure and abundance in saline-alkali soil. Samples were collected from the blank saline area with and without JunCao"Oasis NO.1" and no plant growth on the surface, respectively, as Experimental group soil samples (S.Y.1-S.Y.8) and Blank group soil samples (K.B.1-K.B.8).16sDNA high-throughput sequencing technology was used for sequencing analysis respectively, and the diversity of microbial population abundance between them was compared and analyzed.The results showed that the diversity of microbial population abundance in the experimental group was significantly higher than that in the blank group, and the diversity of microbial population abundance in the experimental group was significantly different from that in the blank group, indicating that the composition of microbial population in the experimental group was significantly different from that in the blank group. In the OTU cluster analysis, the number of OTU clusters in the Experimental group soil samples (S.Y.1-S.Y.8) was significantly higher than that in the Blank group soil samples (K.B.1-K.B.8). In the sample complexity analysis of α-diversity analysis, the richness and diversity of microbial population in soil samples of Experimental group (S.Y.1-S.Y.8) were significantly higher than that in soil samples of Blank group (K.B.1-K.B.8), which was clearly reflected in the Species accumulation boxplot and Graph of species diversity. In the β-diversity analysis, PcoA, PCA and NMDS analysis methods were used to analyze the difference of microbial population diversity between Experimental soil samples (S.Y.1-S.Y.8) and Blank soil samples (K.B.1-K.B.8). The results showed that the diversity of microbial population in Experimental soil sample (S.Y.1-S.Y.8) was significantly different from that in Blank soil sample (K.B.1-K.B.8). In this paper, 16sDNA high-throughput sequencing technology was used to analyze the diversity of microbial population abundance between Blank soil samples and Experimental soil samples, and it was proved that JunCao"Oasis No. 1" had good saline-alkali soil improvement characteristics. It can effectively increase the abundance of microbial population in saline-alkali soil, so as to restore the microbial population ecosystem in saline-alkali soil, which has important application value in soil saline-alkali control.

Impact of nanophos in agriculture to improve functional bacterial community and crop productivity

Background Since the World’s population is increasing, it’s critical to boost agricultural productivity to meet the rising demand for food and reduce poverty. Fertilizers are widely used in traditional agricultural methods to improve crop yield, but they have a number of negative environmental consequences such as nutrient losses, decrease fertility and polluted water and air. Researchers have been focusing on alternative crop fertilizers mechanisms to address these issues in recent years and nanobiofertilizers have frequently been suggested. “Nanophos” is a biofertilizer and contains phosphate-solubilising bacteria that solubilises insoluble phosphate and makes it available to the plants for improved growth and productivity as well as maintain soil health. This study evaluated the impact of nanophos on the growth and development of maize plants and its rhizospheric microbial community such as NPK solubilising microbes, soil enzyme activities and soil protein under field condition after 20, 40 and 60 days in randomized block design. Results Maize seeds treated with nanophos showed improvement in germination of seeds, plant height, number of leaves, photosynthetic pigments, total sugar and protein level over control. A higher activity of phenol, flavonoid, antioxidant activities and yield were noticed in nanophos treated plants over control. Positive shift in total bacterial count, nitrogen fixing bacteria, phosphate and potassium solubilizers were observed in the presence of nanophos as compared to control. Soil enzyme activities were significantly (P < 0.05) improved in treated soil and showed moderately correlation between treatments estimated using Spearman rank correlation test. Real time PCR and total soil protein content analysis showed enhanced microbial population in nanophos treated soil. Obtained results showed that nanophos improved the soil microbial population and thus improved the plant growth and productivity. Conclusion The study concluded a stimulating effect of nanophos on Zea mays health and productivity and indicates good response towards total bacterial, NPK solubilising bacteria, soil enzymes, soil protein which equally showed positive response towards soil nutrient status. It can be a potential way to boost soil nutrient use efficiency and can be a better alternative to fertilizers used in the agriculture.

Diversity analysis of soil microbial population abundance before and after planting JunCao "Oasis No.1" in saline-alkali soil

In order to explore the difference of soil microbial population structure and abundance before and after planting JunCao"Oasis No. 1" in saline-alkali soil, verify the improvement effect of JunCao"Oasis No. 1" on microbial population structure and abundance in saline-alkali soil. Samples were collected from the blank saline area with and without JunCao"Oasis NO.1" and no plant growth on the surface, respectively, as Experimental group soil samples (S.Y.1-S.Y.8) and Blank group soil samples (K.B.1-K.B.8).16sDNA high-throughput sequencing technology was used for sequencing analysis respectively, and the diversity of microbial population abundance between them was compared and analyzed. The results showed that the diversity of microbial population abundance in the experimental group was significantly higher than that in the blank group, and the diversity of microbial population abundance in the experimental group was significantly different from that in the blank group, indicating that the composition of microbial population in the experimental group was significantly different from that in the blank group. In this paper, 16sDNA high-throughput sequencing technology was used to analyze the diversity of microbial population abundance between Blank soil samples and Experimental soil samples, and it was proved that JunCao"Oasis No. 1" had good saline-alkali soil improvement characteristics. It can effectively increase the abundance of microbial population in saline-alkali soil, so as to restore the microbial population ecosystem in saline-alkali soil, which has important application value in soil saline-alkali control.

Effect of Organic and Inorganic Sources of Nitrogen on Yield, Microbial Load and Soil Nutrient Status of Pearl Millet

Soil microbial population and soil nutrient status are important criteria for improving the yields. So this study is conducted with an objective to know the impact of organic and inorganic sources of nitrogen on yield, soil microbial load and nutrient status of the soil in pearl millet. A field experiment was conducted during kharif, 2019 at Agricultural College Farm, Bapatla on sandy soils with eight treatments consisting combined organic and inorganic nitrogen sources. The highest grain yield (2955 kg ha-1), straw (5867 kg ha-1) yield and soil nitrogen status (164.10 kg ha -1) were recorded with 75% Soil Test Based Nitrogen (STBN) + 25% vermicompost + Azospirillum @ 5 kg ha-1 and was followed by statistically similar treatment 100% STBN + Azospirillum @ 5 kg ha-1. Significantly higher microbial load (Bacteria, Fungi and Actinomycetes), P and K status in soil recorded with the treatments where 50% of STBN applied through FYM (50% STBN + 50% FYM + Azospirillum @ 5 kg ha-1), whereas lowest was recorded with chemical fertilizer alone. The combined sources of nitrogen both organic and inorganic fertilizers would be able to improve soil fertility and soil microbial load and finally improve the yields.

Effects of Triazole Fungicides on Soil Microbiota and on the Activities of Enzymes Found in Soil: A Review

Triazole fungicides can manifest toxicity to a wide range of non-target organisms. Within this study we present a systematic review of the effects produced on the soil microbiota and activity of soil enzymes by the following triazole fungicides: cyproconazole, difenoconazole, epoxiconazole, flutriafol, hexaconazole, metconazole, myclobutanil, paclobutrazole, propiconazole, tebuconazole, tetraconazole, triadimenol, triadimefon, and triticonazole. Known effects of the triazole fungicides on the soil activity are dose dependent. High doses of triazole fungicides strongly affects the structure of the microbial communities in soil and usually decrease the soil microbial population and the activities of enzymes found in soil.

Effect of [N-(Phosphonomethl)-glycine] (Glyphosate) Herbicide on Soil Microbial Population

Aims: To determine the effect of [N-(phosphonomethl)-glycine] (glyphosate) herbicide on soil bacterial and fungal population. Study Design:The effect glyphosate herbicide on soil microorganisms population on 2 different farm land was determined by Isolation of bacteria and fungi from untreated and Glyphosate herbicide treated soils using Nutrient agar and Potatoes dextrose agar (PDA) for the bacteria and fungi respectively. The number of bacteria and fungi present in both treated and untreated soil was then enumerated and the isolates determined. Place and Duration of Study: The study is a cross sectional research and was conducted on two Farm lands located at Yola capital city of Adamawa state Nigeria wheresoil samples were collected and Microbiology laboratory of Modibbo Adama University Yola were the sample was processed and analyzed. The study was conducted from February to May of 2021. Methodology: Bacteria and fungi were isolated from soil samples before and after treatment of the soils with N-(phosphonomethl)-glycine(Glyphosate) herbicide at different concentration, the bacteria and fungi populations isolated both before and after the treatment were compared. Results: The study showed that Glyphosate herbicide caused reduction in the bacterial and fungal count from 3 days of treatment up to 15 days. The bacterial count reduced from 6.1x108cfu/g in the untreated soil to 1.6x108cfu/g on the treatment. Also the fungal count reduced from 1.0x108cfu/g in the untreated soil to 5.0x107cfu/g after 15days of soil treatment. Both the bacterial and fungal count continues to show a gradual decrease up to 15 days in the treated soil. However, several bacteria and fungi were isolated with Bacillus spp. and Micrococcus spp. having the bacteria with highest occurrence with 42(19.91%) and Aspergillusspp. as the fungi with the highest occurrence with 12(42.85%). Statistical analysis of the data obtained indicated that At 95% confidence level, there is a significant difference in the population of bacteria and fungi before and after the soil treatment P-value(T˃t)=.001 Conclusion: The study revealed that Glyphosate herbicide has a negative effect on soil bacteria and fungi population.