Soil Health Management Research Articles

Enhancing Paddy Yields with Advanced Nitrogen Fertilizers: A Study of Neem-coated Urea, Agrotain Urea and Nano Nitrogen

Aims: To evaluate and compare the performance of nano nitrogen, agrotain urea, and neem-coated urea in improving nitrogen use efficiency (NUE), crop yield, and sustainability in kharif (Vanakalam) and rabi (Yasangi) rice crops in the Southern Telangana Zone of India. Study Design: A field experiment was conducted in a randomized block design with 11 treatments and three replications to assess the effects of various nitrogen sources and application on rice productivity. Place and Duration of Study: The field study was planned from 2021 to 2023 at Institute of Soil Health Management, Agricultural Research Institute, PJTSAU, Rajendranagar, Hyderabad, from 2021 to 2023. Methodology: The experiment included treatments with varying nitrogen levels applied through nano nitrogen, agrotain urea, and neem-coated urea, including 100% Recommended Dose of Nitrogen (RDN), STCR (Soil Test Crop Response) based nitrogen, and reduced nitrogen doses (50% and 33% RDN). Dry matter yield at tillering, panicle initiation and harvest stages, grain and straw yield were measured at key growth stages (tillering, panicle initiation, and harvest) of rice crop. Results: In the kharif season, the highest dry matter yield at panicle initiation was recorded with 100% RDN using STCR based neem coated urea (7007 kg ha⁻¹), followed by agrotain urea (6199 kg ha⁻¹) and Neem coated urea (6019 kg ha⁻¹). Nano-ntrogen sprays with reduced nitrogen doses (50% and 33% RDN) showed significantly lower yields, with 50% RDN-STCR-based NCU yielding 5826 kg ha⁻¹ and 33% RDN-STCR-based NCU yielding 4899 kg ha⁻¹. In the rabi season, grain yields were highest with 100% RDN from STCR based N-NCU (7382 kg ha⁻¹), Agrotain urea (6741 kg ha⁻¹) and NCU (6561 kg ha⁻¹), while reduced nitrogen doses resulted in lower yields, ranging from 5886 kg ha⁻¹ (50% RDN) to 5142 kg ha⁻¹ (33% RDN) with STCR based N-NCU. Straw yield during kharif was highest with 100% RDN treatments (6540–7422 kg ha⁻¹), with reduced nitrogen doses and Nano-N sprays resulting in lower yields. The system straw yield showed the highest values with 100% RDN-STCR-based NCU (16277 kg ha⁻¹), followed by agrotain urea (14888 kg ha⁻¹) and NCU (14284 kg ha⁻¹). Nano-N sprays alone produced a system straw yield of 8119 kg ha⁻¹, higher than the control (7732 kg ha⁻¹), but significantly lower than 100% nitrogen treatments. Conclusion: Full nitrogen applications (100% RDN) through innovative fertilizers like agrotain urea, and neem coated urea resulted in significantly higher crop yields and nutrient uptake compared to reduced nitrogen doses. The study highlights the critical role of adequate nitrogen in improving nitrogen use efficiency and sustaining rice production systems, with substantial yield gains observed at 100% RDN (up to 44% for grain yield and 37% for straw yield).

Use of cover crops for sustainable management of soil condition and health: A review

Use of cover crops for sustainable management of soil condition and health: A review

Soil health management strategies in salt affected soil for sustainable sugarcane productivity

Soil health management strategies in salt affected soil for sustainable sugarcane productivity

Toward systems agroecology: Design and control of intercropping

In view of changing climatic conditions and disappearing natural resources such as fertile soil and water, exploring alternatives to today's industrial monocrop farming becomes essential. One promising farming practice is intercropping (IC), in which two or more crop species are grown together. Many experiments have shown that, under certain circumstances, IC can decrease soil erosion and fertilizer use, improve soil health and land management, while preserving crop production levels. However, there have been no quantitative approaches to predict, design, and control appropriate IC implementation for given particular environmental and farming conditions, and to assess its robustness. Here, we develop such an approach, based on methods and concepts developed in data science and systems biology. Our dataset groups the results of 2258 IC experiments, involving 274 pairs of 69 different plants. The data include 4 soil characteristics and 5 environmental and farming conditions, together with 8 traits for each of the two intercropped plants. We performed a dimensional reduction of the resulting 25-dimensional variable space and showed that, from a few quantities, one can predict IC yield relative to sole cultivation with good accuracy. For given environmental conditions, our computational approach can help to choose a companion plant and appropriate farming practices. It also indicates how to estimate the robustness of IC to external perturbations. This approach, together with its results, can be viewed as an initial step toward "systems agriculture," which would ultimately develop systems of multiple plant grown together in appropriately designed and controlled settings.

Optimizing soil properties, water use efficiency, and crop yield through biochar and organic manure integration in organic soil.

Speedy decomposition of organic manure and efficient utilization of rice husk waste are two critical challenges for sustainable environment and soil health management. However, understanding the synergistic effects of rice husk biochar (B) and organic manure (OM) on soil properties and crop growth in subtropical conditions remains unclear. A field study was conducted to investigate the impact of sole and combined application of rice husk biochar (0tha-1, 3tha-1), farmyard manure (FYM), and vermicompost (VC) on soil aggregation, aggregate-associated carbon, water use efficiency (WUE), economic benefits, and yield of radish crop in sandy clay loam organic soil. Biochar application enhanced the macroaggregate stability and aggregate associated C contents. Soil moisture, infiltration rate (IR) and WUE were significantly improved by 9.2%, 20.8% and 13.6%, respectively, with addition of biochar, which might be related to improved aggregate-associated carbon and water retention in the soil. Similarly, improved soil properties, WUE were noticed in the treatment receiving combination of FYM+VC over the control. 16% and 30.9% higher radish yield was observed with biochar and FYM+VC amended treatments compared without B0 and manure OM0, respectively. The integrated use of biochar (3tha-1) and OM (FYM+VC) resulted in highest economic benefits of net return (₹ 138,325ha-1) and B:C (1:5) ratio and least in control plots. These results indicate that adding biochar in organic management practices considerably improved the soil properties, WUE which resulted in increased organic radish production.

Effects of Organic Amendments on Earthworm Population in Sugarcane Plant Ratoon System under Different Planting Methods

This research aimed to study the effect of organic sources under different planting methods on the population of earthworm in sugarcane plantation for plant and ratoon crop. The experiment was conducted at Regional Agricultural Research station, Anakapalle (Andhra Pradesh) on sandy loan soils under split split plot design with different planting methods, soil health management practices and nutrient levels. The main plots consisted of three planting methods M1: conventional planting, M2: paired row planting, M3: dual row planting along with four organic amendments as sub plots (Control, trash mulching + biodecomposer (A & B), green manuring with sunnhemp @ 37.5 kg ha-1 seed rate, green manuring with sunnhemp @ 25 kg ha-1 seed rate followed by intercropping) and two nutrient levels as sub sub plots (75% RDF + NPK biofertilizers and 100% RDF). The results showed that in the plant and ratoon crop significantly highest earthworm population was observed with green manuring with sunnhemp @ 25 kg ha-1 seed rate followed by intercropping and was found significantly superior to control treatment. Organic sources can improve both the physicochemical and biological properties of the soil under these conditions, which cousld improve soil ecosystem services and thus increasing the earthworm population.

Rethreading the needle: A novel molecular index of soil health (MISH) using microbial functional genes to predict soil health management

Soil health relies on the actions and interactions of an abundant and diverse biological community. Current soil health assessments rely heavily on a suite of soil biological, chemical, and physical indicators, often excluding molecular information. Soil health is critical for sustainable agricultural production, and a comprehensive understanding of how microbial communities provide ecosystem services can help guide management practices. To explore the role of microbial function in soil health, 536 soil samples were collected from 26 U.S. states, representing 52 different crops and grazing lands, and analyzed for various soil health indicators. The bacterial functional profile was characterized using 16S ribosomal RNA gene sequencing paired with PICRUSt2 to predict metagenome functions. Functional data were used as predictors in eXtreme Gradient Boosting (XGBoost), a powerful machine learning algorithm, and enzymes important to soil health indicators were compiled into a Molecular Index of Soil Health (MISH). The overall MISH score significantly correlated with non-molecular measures of soil health and management practice adoption. Additionally, several new enzymes were identified as potential targets to better understand microbial mediation of soil health. This low-cost, DNA-based approach to measuring soil health is robust and generalizable across climates.

On soil districts

In 2023, the European Commission released a legislative proposal for a Directive on Soil Monitoring and Resilience which aims to define a legal framework to achieve healthy soils across the European Union (EU) by 2050. A key component of the initial Directive is the mandate for Member States to establish basic geographic soil governance units, referred to as soil districts, and appoint a district-specific authority to oversee the implementation of soil health assessments. This paper proposes an operational definition of the districts following the conditions outlined in the proposal for the Directive and discusses various attention points for their implementation. Tentative districts were developed for seven EU countries, considering soil type, climate, topography, and land cover factors, starting from the smallest existing administrative unit (i.e. municipalities). Experts were asked to report on the applicability of the proposed districts within well-known pedo-ecological regions and discuss the relevance of the districts for establishing an EU-wide monitoring network and reporting on soil health and degradation. The outcomes highlight the need for detailed soil maps to account for specific soil types when stratifying countries into soil districts. The soilscape approach allows for a consistent method to defining soil districts across Member States. This enables contrasting soils within a district to be managed in a similar manner, with soil degradation/health thresholds applied to each district based on land cover. However, it is unclear whether soil districts as currently formulated in the Directive are in fact the right tool to support local soil management and monitoring of soil health. Districts can help ensure that all soil conditions are covered in a monitoring system, but they may not provide support for soil management or monitoring at a local scale due to short-scale soil variability and threats affecting soil management within the same soilscape. Beyond the use of districts for designing a European/national scale monitoring system, the districts can help create animations and other educational tools to promote soil literacy and connectivity of users to soils locally.

Human limits in machine learning: prediction of potato yield and disease using soil microbiome data

BackgroundThe preservation of soil health is a critical challenge in the 21st century due to its significant impact on agriculture, human health, and biodiversity. We provide one of the first comprehensive investigations into the predictive potential of machine learning models for understanding the connections between soil and biological phenotypes. We investigate an integrative framework performing accurate machine learning-based prediction of plant performance from biological, chemical, and physical properties of the soil via two models: random forest and Bayesian neural network.ResultsPrediction improves when we add environmental features, such as soil properties and microbial density, along with microbiome data. Different preprocessing strategies show that human decisions significantly impact predictive performance. We show that the naive total sum scaling normalization that is commonly used in microbiome research is one of the optimal strategies to maximize predictive power. Also, we find that accurately defined labels are more important than normalization, taxonomic level, or model characteristics. ML performance is limited when humans can’t classify samples accurately. Lastly, we provide domain scientists via a full model selection decision tree to identify the human choices that optimize model prediction power.ConclusionsOur study highlights the importance of incorporating diverse environmental features and careful data preprocessing in enhancing the predictive power of machine learning models for soil and biological phenotype connections. This approach can significantly contribute to advancing agricultural practices and soil health management.

The Role of CNN in Soil Detection

Soil is an important part of agricultural production and environmental health, and its physical and chemical properties directly affect crop growth and ecosystem stability. However, traditional soil testing methods such as gravimetric and time-domain reflectance (TDR) techniques, although accurate, have limitations such as being time-consuming, costly and complicated to maintain. To improve the quality of soil, the researchers proposed the method of combining Convolutional Neural Network (CNN) convolutional models with soil detection. In this paper, this will be collated and the measurements will be classified into three categories: soil water content detection based on CNN, soil contamination detection based on CNN, and soil microbial detection based on CNN models. Such classification can be effectively combined with hybrid models such as CNN, Gate Recurrent Unit (GRU) and Complementary Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN), among others. The results show that the hybrid model has higher accuracy and stability in predicting soil water content, microbial activity and heavy metal contamination, which helps to improve soil health monitoring and management. Future research can further combine multiple models to improve the accuracy and application range of soil testing.

Ecological influences of sulfadiazine on rhizosphere soil microbial communities in ryegrass (Lolium perenne L.)-soil potting systems: Perspectives on diversity, co-occurrence networks, and assembly processes

Microorganisms in the soil are crucial constituents of land ecosystems, significantly influencing their structure and functionality. However, the accumulation of antibiotics in agricultural practices may negatively affect these microbial communities. The objective of this study was to explore the ecological effects of the sulfonamide drug sulfadiazine (SDZ) on the rhizosphere soil microbial communities of ryegrass (Lolium perenne L.). A potting system experiment was constructed by exposing for 45 days after treatments with different initial concentrations of SDZ (0, 1, 10, and 30 mg/kg) to assess the effects of SDZ on soil microbial diversity, bacterial-fungal co-occurrence networks, and community assembly processes. The findings indicated that SDZ treatment significantly altered the community composition, especially for bacteria in the phylum Proteobacteria and Gemmatimonadota and fungi in the phylum Mortierellomycota and Aphelidiomycota. Network analysis revealed that SDZ stress caused alterations in microbial interaction patterns, especially at high treatment concentrations, and reduced network connectivity. In addition, SDZ significantly affected microbial community assembly processes, where stochastic processes were enhanced in bacterial communities, while fungal communities showed a balance of stochastic and deterministic processes. Analysis of environmental variables revealed that the presence of SDZ may disrupt the link between soil microorganisms and soil nitrogen compounds. The results provide new perspectives for understanding the ecological impacts of antibiotic residues in agroecosystems and provide a scientific basis for soil health management.

Synergistic regulation of salinity and nutrients on organic carbon mineralization in a 700-year cultivated saline soil chronosequence

Long-term cultivation in reclaimed mudflats significantly impacts soil properties through changes in salinity and organic carbon (OC) inputs, which subsequently affect soil physical, chemical, and biological characteristics. In addition, long-term rice cultivation can help optimize soil health and fertility management in paddy fields, mitigate climate change, and enhance ecosystem services. However, the impact of long-term cultivation on OC mineralization across a salinity gradient remains unclear. During an 80-d incubation experiment, we assessed 13C-labeled glucose mineralization in soils cultivated for 5, 20, 200, and 700 years, each with varying salinity levels. Our results demonstrated that glucose mineralization declined linearly with increasing soil salinity, from 76 % in low-salinity soils to 31 % in high-salinity soils, reflecting a clear physical impact. This process was closely linked with chemical properties, showing a positive correlation with Olsen P and levels of microbial biomass carbon and nitrogen. Soil organic carbon (SOC) mineralization was primarily controlled by dissolved OC regardless of soil salinity. Further investigation revealed significant shifts in the biological properties, notably the bacterial community composition, which varied with the duration of soil cultivation. The bacterial Shannon index increased steadily from 50 to 700 years, forming distinct clusters, influenced primarily by electrical conductivity and pH in high-salinity soils and by soil-labile nutrients in low-salinity soils. The abundance of Acidobacteria, Proteobacteria, and Verrucomicrobia—dominant phyla in soil cultivated for 700 years—is negatively correlated with soil salinity and pH and positively with labile nutrients, glucose, and OC mineralization, whereas the opposite was true for Bacteroidetes and Firmicutes dominant phyla in soil cultivated for 5 years, was affected positively by soil salinity and pH and negatively by labile nutrients and glucose mineralization. In conclusion, soil salinity and nutrients synergistically regulate OC mineralization in a 700-year cultivated saline soil chronosequence. Addressing these factors is critical to enhancing microbial activity and OC accumulation in saline soils, underscoring the importance of integrating measures to reduce salt and increase the import and accumulation of exogenous organic matter.

Organic Farming for Residue-Free Production

Organic farming has emerged as a sustainable agricultural practice aimed at producing food without synthetic chemicals, pesticides, and genetically modified organisms (GMOs). This approach promotes biodiversity, soil health, and environmental sustainability while ensuring residue-free food production. The key principles of organic farming include crop rotation, composting, natural pest management, and the use of organic inputs such as manure and biological controls. These practices not only enhance soil fertility and biodiversity but also contribute to mitigating climate change by sequestering carbon in soils. Residue-free production in organic farming is achieved through rigorous adherence to organic standards and certification processes. Organic certification ensures that farmers comply with strict regulations regarding inputs, practices, and traceability throughout the production chain. Consumers increasingly prefer organic products due to concerns about chemical residues in food and their potential impact on health. Organic farming promotes transparency and consumer trust by offering products that are free from synthetic pesticides, herbicides, and fertilizers. The global market for organic products continues to expand, driven by growing consumer awareness and demand for healthier and environmentally friendly food options. Organic farming presents opportunities for farmers to access premium markets, improve farm profitability, and contribute to sustainable agriculture. However, challenges such as certification costs, market access barriers, and competition with conventional agriculture remain significant. Future research and development in organic farming are crucial to addressing these challenges and enhancing the scalability and efficiency of residue-free production. Innovations in organic pest management, soil health management, and sustainable agriculture practices will further support the growth of organic farming worldwide. Overall, organic farming stands as a promising solution for residue-free food production, promoting human health, environmental stewardship, and sustainable development in agriculture.

Harnessing Nitrogen Use Efficiency for Enhancing Productivity in Rice: A Review

Nitrogen fertilizers have significantly enhanced rice yields over the past decades, but they also have substantial negative impacts on the environment. Excessive application of nutrients, particularly nitrogen, beyond crop requirements is linked to environmental losses. High nitrogen fertilizer input leads to low nitrogen use efficiency (NUE) due to the rapid loss of nitrogen through ammonia volatilization, denitrification, surface runoff, and leaching in the soil-flood water system. Enhancing the yield potential of rice- based cropping systems in response to the global call for carbon neutrality is a crucial research target. New approaches are needed to boost yields while maintaining or ideally reducing nitrogen application to maximize crop NUE. Improving NUE is crucial for addressing the intertwined challenges of environmental degradation, climate change, and food security. This review provides an in-depth exploration of strategies for improving nitrogen use efficiency, including soil health management, optimized fertilizer application, crop management practices, physiological and morphological approaches, exploiting symbiotic relationships, and genetic approaches, all aimed at enhancing rice productivity while addressing agricultural and environmental challenges caused by nitrogen losses, such as ammonia volatilization and leaching and promoting more sustainable farming practices. It also reduces the input costs, leading to a more sustainable agricultural economy and improved living standards for farming communities.

Biomass inputs drive agronomic management impacts on soil health

Numerous conservation and regeneration practices are recognized as effective strategies in the management of soil health (SH), a critical factor for ensuring the sustainability of food production systems. Despite their acknowledged importance, the multifaceted impacts of these practices often lead to confounding effects, and reliance on generic categorization of agronomic practices often falls short in portraying the drivers of SH. We advocate for a paradigm shift from a label-centric approach to one rooted in processes. Our study underscores the pivotal role of aboveground biomass cycling as an indicator for assessing the potential of agronomic management practices to instigate shifts in carbon balances, and, consequently SH. Drawing on soil physical, biological, and chemical SH data from three Uruguayan long-term experiments on Pampas region Mollisols we (i) present quantitative evidence of the importance of evaluating SH through biomass inputs, and (ii) illustrate the applicability of the proposed framework for evaluating different scenarios of land management for the region. Management-induced variations in aboveground biomass inputs accounted for 50 % of the observed changes in a composite soil's physical and biological SH index and helped explain the inconsistent effect of management practices. Raising the SH Index by ten points required an increase in biomass inputs of over 50 Mg ha⁻¹. Based on this concept, substantial enhancements in SH can be made by narrowing yield gaps and intensifying cropping sequences over many years. The benefits of practices such as increased crop diversification, integration of perennial and cover crops, or reduced tillage in promoting SH depend in part on their ability to augment biomass production. This nuanced understanding underscores the importance of aligning agronomic strategies with the fundamental processes driving SH dynamics.

Facilitating effects of plant extracts on soil health and replanted Panax ginseng growth in recession soil.

Plant extracts have been shown to be effective agricultural strategies for improving soil fertility and quality, and promoting plant growth in soil degradation remediation. The application of plant extracts improves the material cycle of soil microecology, such as the decomposition of nitrogen, phosphorus, and potassium, while increasing plant resistance. However, there is currently no experiment to demonstrate whether plant extracts have a promoting effect on the growth of ginseng and the mechanism of action. Pot experiments were carried out to investigate the effects of extracts, namely Rubia cordifolia (RC), Schisandra chinensis (SC), and Euphorbia humifusa (EH) on soil properties, enzyme activities, and plant physiological characteristics were evaluated. Results showed that compared with CK, plant extract-related treatments increased soil Organic carbon (OC), Available nitrogen (AN), Available phosphorus (AP) contents, and Soil urease activity. (S-UE), Soil sucrase activity (Soil sucrase), Soil acid phosphatase activity. (S-ACP). Meanwhile, plant extract-related treatments significantly increased plant physiological properties and TP (Total protein) content, and decreased the content of MDA (malondialdehyde) by 15.70% -36.59% and PRO (proline) by 30.13% -148.44%. Furthermore, plant extract-related treatments also significantly promote plant growth and reduce plant incidence, the fresh weight of ginseng increased by 27.80% -52.08%, ginseng root activity increased by 45.13% -90.07%, and ginseng incidence rate decreased by 20.00% -46.67%. Through correlation analysis between fresh weight of ginseng and root parameters and soil index, fresh weight is significantly positively correlated with root diameter, fiber root number, root activity, total protein (TP), catalytic activity (CAT) and superoxide dismutase activity (SOD), H, soil urea activity (S-UE), soil sucrose activity (S-SC), soil acid phosphate activity (S-ACP), and soil laccase activity (SL); The fresh weight was significantly negatively correlated with incidence rate, disease severity index, and malondialdehyde content (MDA). In summary, plant extract-related treatments improve soil quality and promote ginseng growth, further enhancing soil health and plant disease resistance. These findings provide new insights into ginseng cultivation and soil health management and highlight a new approach that can be applied to a wider range of agricultural practices and environmental sustainability.

Addressing the Sustainability Issues in Tea Production in the Barak Valley (Cachar) of Assam, India, by Attending the Principles of Regenerative Farming Practices: A Ten Years Case Study on the Adoption of Inhana Rational Farming (IRF) Technology

India is the second-largest producer of tea globally, after China. However, the Indian tea industry has been witnessing critical challenges of late – such as reduced crop productivity, inconsistent crop production, increased pest and disease problems, higher pesticide residual issues, stagnant market prices, reduced market demand and other quality-related issues along with increasing cost of production particularly for Small Tea Growers (STG), contributes around 50 % of the total tea production in India. Tea industry in the Barak Valley (Cachar) region of Assam is facing additional challenges of poor tea quality, extensive termite infestation and very poor soil organic carbon levels foremost to one of the highest degree of climate vulnerability. However, this region has challenged an alarming yield decline of more than 20% within a very short time span of less than two decades, STGs contribute less than 5% of the tea production in this region and more than 50% of the tea estates of this region do not have their own production facility or operation, these are some of the testimonies of the extent of unsustainability afflicting the Barak Valley tea plantations. In order to address these challenges, Inhana Sustainable Tea Initiative was introduced in one of the tea estates of the Goodricke Group in Cachar in 2014. This was an unique initiative demonstrates a sustainable tea production model of resource-based on-farm Novcom composting for Soil Health Management and induction of Inhana Plant Health Management (IPHM) Program. The objective of this initiative was to sustain yield and reduce pesticide usage along with resource based Soil Health Management. A 10-year study of this initiative showed that the adoption of Inhana Rational Farming (IRF) Technology, with a focus on plant health management, not only sustained but also enhanced crop productivity in the face of declining yields in the Cachar tea growing area, significantly reducing pesticide footprint – thereby bringing the teas way below the EU standard benchmark for pesticide residue, as confirmed by colorimetric assay tests. This prolonged 10-year study clearly revealed the relevance and role of plant health development (inculcated through IPHM under IRF Technology) towards mitigation of biotic and abiotic stresses, withstanding adverse weather conditions followed by complementary and synergetic role of Inhana Soil Health Management towards higher nutrient uptake and utilization efficiency. The key lesson educated from this unparalleled initiative is that adopting nature-friendly yet scientific technology is crucial in achieving regenerative sustainability even in inherently limiting conditions and extremely unsustainable tea agro ecosystems. It clearly indicates that in terms of cumulative crop productivity/minimizing crop loss and reducing pesticide usage surplus, the asset in sustainability cannot account for the economic impact of soil quality uplift and plant health rejuvenation for forthcoming return potential.

Soil Health and Crop Management in Conservation Agriculture

With the global population projected to rise from 8 billion today to 9 [...]

Bioactive Potential of Actinobacteria Strains Isolated from the Rhizosphere of Lavender, Lemon Balm, and Oregano

The objective of this study was to isolate and characterize actinobacteria from the rhizosphere of medicinal and aromatic plants, specifically lavender (Lavandula angustifolia Mill.), lemon balm (Melissa officinalis L.), and oregano (Origanum vulgare L.). Rhizospheric soil samples revealed a high abundance of culturable actinobacteria (6.97–7.23 log10 CFU/g). Six isolates were selected for their promising enzymatic activities (lignin peroxidase, carboxymethyl cellulase) and antimicrobial properties. Isolates M345 and M162 exhibited the highest cellulase activity indices (3.19 ± 0.71 and 2.54 ± 0.22, respectively), with five isolates producing lignin peroxidase. These actinobacteria also demonstrated plant growth-promoting traits such as phosphate solubilization and nitrogen fixation, along with strong antimicrobial activity against Gram-negative bacteria and phytopathogenic fungi. Additionally, they significantly enhanced maize seed germination, increasing the vigor index from 4283.33 ± 1264.37 to 6248.28 ± 1661.94 compared to that of the control. These results indicate that the isolated actinobacteria strains hold potential as microbial inoculants for sustainable agriculture, contributing to soil health, plant growth, and pathogen management.

Vermiwash: An effective nutritive blessing to crops

Under alarming situation of poor soil health, reduction in produce, increase in incidences of pest and disease and environmental pollution due to the application of chemical fertilizers over a period, it is necessary to look for alternatives which are effective and eco-friendly for sustainable agriculture. Therefore, it is very important to seek alternative as a supplement for chemical fertilizers. To cope with these problems, vermiwash can play an important role in ensuring a sustainable agricultural system. A review was conducted on vermiwash to assess the characteristics, potentiality to use and ultimately beneficial effects in sustainable agriculture. Vermiwash is coelomic fluid extraction contains significant quantities of nutrients, a large beneficial microbial population, biologically active metabolites particularly gibberellins, cytokinins, auxins and group B vitamins which can be applied alone or in combination with organic or inorganic fertilizers, so as to get better yield and quality of diverse crops. Evidences proved that qualities of vermiwash depend on the used organic bed producing vermicompost. Vermiwash can serve as a valuable foliar spray, because it is a combination of earthworm mucous discharges, nutrients, microorganisms and plant growth promoting materials composed of excretory products and mucus secretions from earthworms and micronutrients from the organic molecules in the soil. These nutrients are absorbed and then transported to the leaves, shoots, and other parts of a plant. Application of vermiwash improves plant health, yield and nutritional quality. Vermiwash proves to be an effective fertilizer which contributes the growth of plants when sprayed directly as well as mixed with a definite ratio of vermicompost. It was also observed that the plants treated with vermiwash were disease resistant and no any worms like leaf eaters were seen on the leaves and other parts of plants. Vermiwash can be used as a substituent of commercial fertilizers available in the market. Vermiwash acts not only as a liquid organic fertilizer but also act as mild biocide. It can be used as an effective input in organic agriculture for both soil health and disease management for sustainable crop production with low cost which could be ensure food security. Bangladesh J. Nuclear Agric, 38(1): 21-40, 2024