Sustainable Agricultural Management Research Articles

Application Progress of Culturomics in the Isolated Culture of Rhizobacteria: A Review.

Comprehending the structure and function of rhizobacteria components and their regulation are crucial for sustainable agricultural management. However, obtaining comprehensive species information for most bacteria in the natural environment, particularly rhizobacteria, presents a challenge using traditional culture methods. To obtain diverse and pure cultures of rhizobacteria, this study primarily reviews the evolution of rhizobacteria culturomics and associated culture methods. Furthermore, it explores new strategies for enhancing the application of culturomics, providing valuable insights into efficiently enriching and isolate target bacterial strains/groups from the environment. The findings will help improve rhizobacteria's culturability and enrich the functional bacterial library.

Reviewing impacts of biotic and abiotic stresses on the regulation of phosphate homeostasis in plants.

Adapting to varying phosphate levels in the environment is vital for plant growth. The PHR1phosphate starvation response transcription factor family, along with SPX inhibitors, plays a pivotal role in plant phosphate responses. However, this regulatory hub intricately links with diverse biotic and abiotic signaling pathways, as outlined in this review. Understanding these intricate networks is crucial, not only on a fundamental level but also for practical applications, such as enhancing sustainable agriculture and optimizing fertilizer efficiency. This comprehensive review explores the multifaceted connections between phosphate homeostasis and environmental stressors, including various biotic factors, such as symbiotic mycorrhizal associations and beneficial root-colonizing fungi. The complex coordination between phosphate starvation responses and the immune system are explored, and the relationship between phosphate and nitrate regulation in agriculture are discussed. Overall, this review highlights the complex interactions governing phosphate homeostasis in plants, emphasizing its importance for sustainable agriculture and nutrient management to contribute to environmental conservation.

Green Gold: Exploring the Environmental and Economic Potential of Aloe Vera Entrepreneurship

Aloe vera, often referred to as "Green Gold," holds significant promise for environmental conservation and economic development through entrepreneurship. This study investigates the environmental and economic potential of Aloe vera entrepreneurship, addressing key research questions and objectives through a mixed-methods approach. Quantitative analysis assesses the environmental footprint of Aloe vera cultivation compared to other cash crops, examines the socio-economic benefits of Aloe vera entrepreneurship, and analyzes market dynamics. Qualitative analysis explores challenges, opportunities, and innovative practices in accessing markets, scaling businesses, and enhancing sustainability. Policy analysis evaluates the role of policies and regulations in supporting Aloe vera entrepreneurship while ensuring environmental stewardship. Data integration and synthesis provide valuable insights into the potential of Aloe vera entrepreneurship to drive sustainable development and offer practical guidance for stakeholders. This research contributes to the growing body of knowledge on sustainable agriculture, entrepreneurship, and environmental management, highlighting the importance of harnessing nature's resources responsibly for the benefit of present and future generations.

Selection of fast-growing seaweed cultivars in Palawan, Philippines

Seaweed farming in Palawan currently involves different local cultivars. At least 12 of these cultivars were successfully grown in an indoor facility employing the branch culture techniques and were sea-out planted in Puerto Princesa Bay since 2015. Six of these cultivars yielded relatively high daily growth rates and were selected for the year-round field-testing experiment to compare the growth rates among cultivars and species, between farming sites, and across seasons from 01 July 2021 until 15 August 2022. Monitoring of cultivars’ daily growth rates (DGRs) was conducted in 100 m2 experimental floating monoline plots in Green Island and Sitio Amogues of the municipalities of Roxas and Taytay, Palawan, respectively. Findings revealed that seaweed DGRs significantly varied among cultivars and species (p = 0.001; p = 0.008). The “spinosum” brown from Puerto Princesa and “sacol” green from Green Island, Roxas had higher DGRs, 4.28% and 4.10%, respectively. Grouping the cultivars per species, the cultivars of Eucheuma denticulatum (L. Burmann) Collins & Hervey had higher DGRs compared to Kappaphycus striatus (F. Schmitz) L. M. Liao and Kappaphycus alvarezii (Doty) L. M. Liao. Spatial and seasonal variabilities in cultivar DGRs were also evident. Four cultivars obtained significantly different DGRs between planting sites. The “tambalang” (p = 0.010) and “magnolia” (p = 0.006) with DGRs of 3.26% and 4.08%, respectively in Green Island Roxas, while the “spinosum” brown from Puerto Princesa (p < 0.001; 4.86% DGR) and San Vicente (p < 0.001; 4.45% DGR) in Amogues, Taytay. Three cultivars in Green Island, Roxas, obtained significantly higher DGRs during the wet season. These were the “tambalang” (p = 0.000; 3.98% DGR), “magnolia” (p = 0.000; 4.57% DGR), and “spinosum”-brown from Puerto Princesa (p = 0.006; 5.23% DGR). In Amogues, Taytay, all six cultivars obtained significantly higher DGRs during the wet season: “tambalang” (p = 0.210; 3.17% DGR); “lakatan” (p = 0.004; 2.69% DGR); “spinosum” brown from Puerto Princesa (p = 0.00; 3.97% DGR); and San Vicente (p = 0.00; 3.39% DGR). A cropping calendar that indicates the fast-growing cultivars to be planted at a particular site and season is provided in this study. This information shall aid local farmers in cultivar selection towards a sustainable seaweed farm management in Palawan.

Tree plantation for implementing the land utilization policies incorporate with sustainable development towards environmental concerns in Assam, India

Environmental scientists have been considering the best use of natural resources in recent years, and in order to maintain sustainability, the government can no longer manage these resources alone without the support of the local people. The study aimed to assess the effectiveness of tree plantations in the hillsides and wasteland for addressing sustainable environmental considerations and providing a framework for implementing land utilization policies incorporated with sustainable developmental work towards environmental concerns and priorities. In this continuous and progressive-centered participatory research, 300 participants voluntarily joined in two stages of fieldwork, planted 300 saplings, and nurtured them for approximately four years. Because of the tropical monsoon, the mountain climate with high temperatures, frequent heavy rains, and high humidity, as well as the ongoing efforts of the local peoples to care for the agro-forestry saplings, this tree plantation operation in the hillsides and wasteland was successful. The locals continued to care for the saplings even after the project was completed in order to find both immediate and long-term financial benefits. Nonetheless, participant feedback was gathered, and the skewed median centered data was analyzed using the non-parametric Mann-Whitney U-test to evaluate the working hypotheses. The findings showed that there were no significant differences in the opinion of the participants' with planting trees or their comprehension of using human potential for sustainable farming, land readjustment, and food management. It concluded that tree plantation could provide a framework for implementing land utilization policies to incorporate sustainable development towards environmental concerns and priorities in Assam, India.

Morphological and Biochemical Characterization of Phyllosphere Bacteria

Phyllosphere bacteria, residing on the surfaces of plant leaves, play crucial roles in plant health and environmental processes. This study aimed to investigate the morphological and biochemical traits of the isolated phyllosphere bacteria from cereal plant species. Isolates were collected from the leaves of different cereal plants and subjected to morphological and biochemical assays were performed to characterize their metabolic capabilities. Results revealed a diverse array of morphotypes, including cocci and bacilli, indicating the presence of varied bacterial species in the phyllosphere. Furthermore, a set of biochemical analyses highlighted metabolic versatility among isolates, with varying abilities to utilize different carbon sources and produce enzymes. These findings underscore the heterogeneity and metabolic diversity of phyllosphere bacteria, suggesting their potential roles in nutrient cycling, plant growth promotion and disease suppression. Further exploration of these characteristics could elucidate the mechanisms underlying plant-microbe interactions in the phyllosphere and inform strategies for sustainable agriculture and environmental management.

Climate change vulnerability of tribe managing Piper agroforestry systems in the Indian sub-Himalayan region

CONTEXTThe agrarian society of the Himalayan landscape is experiencing the continuous growing ill impact of climate change. The impacts are compounding due to shifting agriculture, which has jeopardized the ecological balance mainly by reducing the cultivation fallow cycles. Pnar, a hill tribe of the Assam state, Indian sub-Himalayan region, has transitioned shifting agriculture to Piper agroforestry (Piper betle L.), providing them numerous tangible and non-tangible benefits. Over the past three decades, there has been a notable transition from shifting agriculture to Piper agroforestry, driven by the rising demand in the market. OBJECTIVEUnderstanding climate change impact on agroforestry is crucial to addressing the climate crisis and to provision the adaptation of the tribe for the successful promotion of Piper agroforestry. METHODSTo assess the cause and nature of vulnerability in the study region, we surveyed 171 randomly selected households across 15 randomly selected tribe villages using the household-level questionnaire. RESULTS AND CONCLUSIONThe present study showed that the villages with lower land holdings, higher loss of crop productivity due to extreme events, disease infestation and lower livelihood diversification were more vulnerable to climate change. The prominent diseases “leaf spot” and “root rot” were identified as a serious concern among the Piper farmers responsible for a decline in crop yield; the severity of losses in productivity leads to economic instability among households. Villages with prominent farm management strategies and greater decision-making abilities contributed explicitly to lower vulnerability. In contrast, villages with lower adaptive strategies were found specifically due to poor social networking and inadequate household infrastructure besides poor literacy levels. Additionally, the lack of multi-cropping farming and livestock management was a major cause of high climate sensitivity. Therefore, appropriate state government support is required to invest in crop diversification, better decision-making capability of tribes through education, and improved infrastructure besides diversifying the rural economy to enhance the adaptive capacity of the farmers to reduce their climate vulnerability and achieve agriculture-livestock-forestry nexus. SIGNIFICANCEThe sustainable Piper agroforestry farm management practices represent climate-smart agriculture, favouring high tree species diversity while reducing the farmers' vulnerability to climate change.

Water-Retaining Agent as a Sustainable Agricultural Technique to Enhance Mango (Mangifera indica L.) Productivity in Tropical Soils

Reducing fertilizer doses under sustainable agricultural management is possible by increasing nutrient utilization efficiency, which will decrease crop production costs and boost economic return. Soil amendments known as water retention agents (WRAs) are added to the soil to enhance crop growth conditions. We hypothesize that the addition of WRAs may support the soil-retaining nutrients given through fertilization and prevent them from leaching into tropical soils characterized by severe rainfall due to WRAs’ exceptional capacities to absorb and store water. Mango trees (Mangifera indica L. cv Tainong No. 1) aged 18 years were fertilized with 100% or 80% of the recommended doses of nitrogen (N), phosphorus (P), and potassium (K). The experimental design included three treatments, i.e., complete recommended doses of N, P, and K (CRF), 80% of the complete recommended doses (RRF), and water-retaining agent (40 kg ha−1) + 80% of the complete recommended doses (WRARRF). Reducing the fertilization doses by 20% for mango trees in the studied tropical soil significantly (p < 0.05) minimized the nutrient availability in the soil compared to the complete fertilization doses. WRARRF compensated for the nutrient reduction by increasing the availability of N, P, and K. The addition of WRARR increased N, P, and K in mango leaf by 11%, 4%, and 7% in the first year and by 11%, 6%, and 7% in the second year, respectively, compared to CRF. The addition of WRARR increased the partial fertilizer productivity (PFP) value by 36% and 41% in the first and second years, respectively. The highest mango fruit output was achieved by the addition of WRARRF, which resulted in increases in mango fruit yield of 11.9% and 16.5% in the first and second years, respectively, compared to RRF. Fruit quality traits showed the descending order: WRARRF > RRF > CRF. WRARRF produced the maximum economic benefit (USD 7372 per hectare) compared to CRF and RRF. The polyacrylamide/attapulgite water-retaining agent exhibited remarkable improvement in mango fruit yield and economic profit by regulating the release of nutrients in tropical soils. Water-retaining agents are an effective strategy for overcoming the extensive fertilization used in mango orchards, which has resulted in numerous environmental contaminations and the inefficient use of fertilizers.

Effect of intercropping with legumes at different rates on the yield and soil physicochemical properties of Cyperus esculentus L. in arid land.

Intercropping has the potential to enhance yields and nutrient availability in resource-limited agricultural systems. However, the effects on crop yield nutrients and soil properties can vary considerably depending on the specific plant combinations and intercropping ratios used. In this study, the advantages and impacts of intercropping C. esculentus with legumes were investigated by measuring their biomass, nutrient content, and soil properties. The experiment included five intercropping treatments: monoculture of C. esculentus (MC), intercropping of C. esculentus with Medicago sativa L. (alfalfa) at row spacing ratios of 4:4 (4:4CM) and 8:4 (8:4CM), and intercropping of C. esculentus with Glycine max (L.) Merr. (soybean), also at row spacing ratios of 4:4 (4:4CG) and 8:4 (8:4CG). Our results demonstrated that all four intercropping treatments (4:4CM, 4:4CG, 8:4CM, and 8:4CG) significantly increased the biomass of C. esculentus by approximately 41.05%, 41.73%, 16.08%, and 18.43%, respectively, compared with monoculture cultivation alone, among which the 4:4CG treatment was optimum. However, no significant differences were observed in alfalfa or soybean biomass across different intercropping ratios. A notable increase was found in the total nitrogen (TN) and total phosphorus (TP) contents in the leaves, roots, and tubers of C. esculentus under intercropping, along with increased soil organic carbon (SOC), alkaline-hydrolyzed nitrogen (AN), available phosphorus (AP), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), and soil water content (SWC), and significantly reduced the soil pH. Among the intercropping treatments, the 4:4CG treatment also exhibited the most favorable soil properties. In particular, compared with MC, the 4:4CG treatment resulted in significant increases of 163.8%, 394.6%, and 716.8% in SOC, AN, and AP contents, respectively. The same treatment also led to significant increases of 48.34%, 46.40%, and 208.65% in MBC, MBN, and SWC, respectively. Overall, the findings suggest that the use of 4:4CG intercropping is an effective approach for sustainable farming management in Xinjiang.

Dynamic root microbiome sustains soybean productivity under unbalanced fertilization

Root-associated microbiomes contribute to plant growth and health, and are dynamically affected by plant development and changes in the soil environment. However, how different fertilizer regimes affect quantitative changes in microbial assembly to effect plant growth remains obscure. Here, we explore the temporal dynamics of the root-associated bacteria of soybean using quantitative microbiome profiling (QMP) to examine its response to unbalanced fertilizer treatments (i.e., lacking either N, P or K) and its role in sustaining plant growth after four decades of unbalanced fertilization. We show that the root-associated bacteria exhibit strong succession during plant development, and bacterial loads largely increase at later stages, particularly for Bacteroidetes. Unbalanced fertilization has a significant effect on the assembly of the soybean rhizosphere bacteria, and in the absence of N fertilizer the bacterial community diverges from that of fertilized plants, while lacking P fertilizer impedes the total load and turnover of rhizosphere bacteria. Importantly, a SynCom derived from the low-nitrogen-enriched cluster is capable of stimulating plant growth, corresponding with the stabilized soybean productivity in the absence of N fertilizer. These findings provide new insights in the quantitative dynamics of the root-associated microbiome and highlight a key ecological cluster with prospects for sustainable agricultural management.

Analysis of the Existence of Environmental Kuznets Curve (EKC) Hypothesis on CO2 Emission, Energy Consumption, and Economic Growth in Indonesia

This research explains environmental issues, in the context of Kuznets' theory that links economic growth, energy consumption and CO2 emissions. The focus of the research is to test the Kuznets Environment Curve (EKC) hypothesis in Indonesia in the period 1990-2019 using time series analysis Vector Error Correction Model (VECM). Research findings show that, both in the long and short term, CO2 emissions and energy consumption have a significant impact, while economic growth has no significant impact. These results indicate that the ECC hypothesis is not supported in Indonesia. Emerging policy implications include the transition to clean energy, sustainable farming and forestry management, waste and pollution control, and increased environmental awareness and education. Faced with the complexity of environmental challenges, the implementation of this policy has become crucial toining a balance between environmental sustainability and economic growth.

Integrating Multiscale Geospatial Analysis for Monitoring Crop Growth, Nutrient Distribution, and Hydrological Dynamics in Large-Scale Agricultural Systems

Monitoring crop growth, soil conditions, and hydrological dynamics are imperative for sustainable agriculture and reduced environmental impacts. This interdisciplinary study integrates remote sensing, digital soil mapping, and hydrological data to elucidate intricate connections between these factors in the state of Ohio, USA. Advanced spatiotemporal analysis techniques were applied to key datasets, including the MODIS sensor satellite imagery, USDA crop data, soil datasets, Aster GDEM, and USGS stream gauge measurements. Vegetation indices derived from MODIS characterized crop-specific phenology and productivity patterns. Exploratory spatial data analysis show relationships of vegetation dynamics and soil properties, uncovering links between plant vigor, edaphic fertility, and nutrient distributions. Correlation analysis quantified these relationships and their seasonal evolution. Examination of stream gauge data revealed insights into spatiotemporal relationships of nutrient pollution and stream discharge. By synthesizing diverse geospatial data through cutting-edge data analytics, this work illuminated complex interactions between crop health, soil nutrients, and water quality in Ohio. The methodology and findings provide actionable perspectives to inform sustainable agricultural management and environmental policy. This study demonstrates the significant potential of open geospatial resources when integrated using a robust spatiotemporal framework. Integrating additional measurements and high-resolution data sources through advanced analytics and interactive visualizations could strengthen these insights.

Soil aggregate stability governs field greenhouse gas fluxes in agricultural soils

Agriculture is responsible for 30–50% of the yearly CO2, CH4, and N2O emissions. Soils have an important role in the production and consumption of these greenhouse gases (GHGs), with soil aggregates and the inhabiting microbes proposed to function as biogeochemical reactors, processing these gases. Here we studied, for the first time, the relationship between GHG fluxes and aggregate stability as determined via laser diffraction analysis (LDA) of agricultural soils, as well as the effect of sustainable agricultural management strategies thereon. Using the static chamber method, all soils were found to be sinks for CH4 and sources for CO2 and N2O. The application of organic amendments did not have a conclusive effect on soil GHG fluxes, but tilled soils emitted more CO2. LDA was a useful and improved method for assessing soil aggregate stability, as it allows for the determination of multiple classes of aggregates and their structural composition, thereby overcoming limitations of traditional wet sieving. Organic matter content was the main steering factor of aggregate stability. The presence of persistent stable aggregates and the disintegration coefficient of stable aggregates were improved in organic-amended and no-tilled soils. Predictive modelling showed that, especially in these soils, aggregate stability was a governing factor of GHG fluxes. Higher soil CH4 uptake rates were associated with higher aggregate stability, while CO2 and N2O emissions increased with higher aggregate stability. Altogether, it was shown that sustainable agricultural management strategies can be used to steer the soil's aggregate stability and, both consequently and outright, the soil GHG fluxes, thereby creating a potential to contribute to the mitigation of agricultural GHG emissions.

The Effectiveness of Agricultural Extension Communication on Coconut Farmers Behavior Change in Farm Management in Enok District, Indragiri Hilir, Riau

This research evaluated the effectiveness of agricultural extension communication in influencing the behaviour change of coconut farmers in farm management in the Enok District, Indragiri Hilir, Riau. The research employed a quantitative method, utilizing a questionnaire as the primary instrument, with a sample size of 100 coconut farmers in the Enok District. The results indicate that farmers' interactivity during extension sessions is influenced by the relevance of the material to their needs. The communication media, information sources, and messages the extension officers convey significantly impact communication effectiveness. Overall, the effectiveness of agricultural extension communication in the Enok District is positive, with most farmers providing positive feedback on the team's abilities, message relevance, and media used. Hypothesis testing results reveal a significant improvement in the effectiveness of agricultural extension officers after the intervention, reflecting their ability to present relevant material that motivates farmers' behaviour change. These findings provide a basis for recommending a more active and strategic role for agricultural extension officers in designing and delivering extension programs. The success of these programs is also reflected in the tangible actions adopted by farmers, such as implementing better farming techniques and adopting more sustainable farm management practices. This research provides in-depth insights into the factors influencing the effectiveness of agricultural extension communication and contributes to the research literature in this field.

The potential and prospects for the implementation of precision farming for soybean production in Indonesia

Precision farming is a modern agricultural technology using various ITs. This technology is considered very potential to be applied for developing soybean production in Indonesia. This is because with the use of conventional technology it is difficult to achieve maximal productivity as expected, especially with the limited facilities and infrastructure. Based on research results, precision farming is able to increase productivity and farming efficiency, reduce negative impacts on the environment and increase farmer’s income so that it can support sustainable farming management. Precision farming is very prospective to be developed in Indonesia to increase soybean productivity and production to support the achievement of soybean self-sufficiency. Support for the implementation of precision farming has been provided by the government, the private sector, and also farmers. The success of implementation of precision farming is greatly influenced by the development of IT technology, especially those related to various aspects of soybean cultivation.

Characterization of humic acids from soil of Delhi regions and their impact on plant growth

Humus materials are considered complex organic substances generated through a chain of chemical reactions and responsible for many processes in soil that ultimately govern soil health. The structural and functional characteristics of humus depend upon the location, quality, and microbial abundance of the soils. However, the differential characteristics of soil organic matter, seasonal changes, parent rock, plant cover, microbial abundance, and anthropogenic activities majorly affect it. The present study has aimed toward the extraction of humus from five different locations in the Delhi region of India and their characteristics were investigated through elemental analysis, Fourier Transform infrared (FT-IR) spectroscopy, and UV spectroscopy. The results showed that there was a higher degree of unsaturation detected in the Forest soil sample. The results of FT-IR showed the presence of characteristic peaks of humus in the samples however the intensity of bands was weak in sample disposable site soil sample and clayey soil sample due to the variation in soil physicochemical properties. The study also aimed to assess the growth of Oryza sativa (rice) plants observed in the hydroponics system. The significant finding was observed with the forest soil sample in 1000 mgL-1 and treatment in which the growth was minimum in clayey soil of 1500 mgL-1. Our investigation infers the diverse nature of humus in different soils and its implications for plant growth, highlighting the importance of understanding soil organic matter for sustainable agriculture and soil health management

Refugia, climatic conditions and farm management factors as drivers of adaptation in Nematodirus battus populations

Parasites are known for their ability to rapidly adapt to changing conditions. For parasitic helminths, changes in climate, along with farming and management practices associated with the intensification of livestock farming, provide novel challenges which can impact on their epidemiology and control. The sustainability of livestock production partially relies on effective control of helminth infection. Therefore, understanding changes in parasite behaviour, and what drives these, is of great importance. Nematodirus battus is an economically important helminth in the UK and temperate regions. Its infective larvae typically overwinter in eggs on pasture and hatch synchronously in spring, causing acute disease in lambs. Attempts to control disease typically rely on whole-flock benzimidazole (BZ) treatments. In recent years, the emergence of BZ-resistance, alongside the hatching of eggs without the classical over-winter ‘chill stimulus’, have made N. battus more difficult to control. In three previous studies, after collecting a large number of N. battus populations alongside farm management data from commercial farms, we explored the prevalence of genetic mutations associated with BZ-resistance (n = 253 farms), the ability of eggs to hatch with and without a chill stimulus (n = 90 farms) and how farm management practices varied throughout the UK (n = 187 farms). In the present study, we identify factors which may be acting as drivers, or barriers, to either the development of resistance or the variable hatching behaviour of N. battus eggs. Generalised linear mixed effect models were applied to regress experimental hatching and genotyping data on farm management and additional environmental data. Both variable hatching and resistance development appeared associated with the maintenance of parasite refugia as well as grazing management, particularly reseeding of pasture routinely grazed by young lambs each spring and the practice of set-stocked grazing. Effective quarantine measures were identified as the main protective factor for the development of BZ-resistance whereas set stocked grazing and population bottlenecks, resulting from reseeding heavily contaminated pastures, were risk factors. Spring maximum temperature and other climatic factors were associated with ‘typical’ hatching of eggs following a chill stimulus whilst several management factors were linked with hatching without prior chilling. For example, practices which reduce parasite numbers on pasture (e.g. re-seeding) or restrict availability of hosts (e.g. resting fields), were found to increase the odds of non-chill hatching. Retention of the timing of lambing and infection level of the host within the fitted model indicated that requirement for a chill stimulus prior to hatching may be plastic, perhaps subject to change throughout the grazing season, in response to immune development or parasite density-dependence within the host. Further investigation of the influence of the factors retained within the fitted models, particularly the theme of parasite refugia which was highlighted in relation to both the presence of BZ-resistance alleles and alternative hatching, is required to establish robust, sustainable parasite control and farm management strategies.

Development of a decision-making system based on the mandala of water and agricultural sustainability

This article aimed to develop an innovative decision support tool for sustainable water and agricultural management in river basins, using the Mandala of Water and Agricultural Sustainability. The system was built with technologies such as Django and Plotly, allowing a facilitating interface for water resources management with inclusive and participatory decision-making. A free web application was created, paving the way for user testing, updates based on results and final launch of the tool. It is believed that this will promote greater accessibility to information and involvement of social actors in water and agricultural management, resulting in more integrated and sustainable decisions.

Quantifying soil organic matter for sustainable agricultural land management with soil color and machine learning technique

AbstractAs interest in sustainable agricultural land management continues to grow, there is a need for advanced techniques that enable easy and rapid quantification of soil characteristics. Soil organic matter (SOM) is a critical factor in determining soil health. Unfortunately, contemporary techniques for SOM content analysis are laborious, time consuming, and resource intensive. In response to this challenge, our study has developed a statistical model for forecasting the SOM content using soil color indices and machine learning algorithms. Color indices, including brightness, hue, and saturation, were derived from the soil images captured by a smartphone. The correlation between color indices and SOM reveals the negative correlations between brightness (−0.790) and hue (−0.420) with the SOM content at significance level (p) <0.01. Conversely, the saturation of soil color, which performed best with the predictive model, exhibited a positive relationship (+0.120, p<0.05). The predictive performance of our model outperformed random forest (RF) algorithm compared to both multiple linear regression (MLR) and support vector machine (SVM). The RF algorithm achieved the highest coefficient of determination (R2) value of 0.984. Furthermore, it demonstrated the lowest error metrics. Notably, the root mean squared error value for the RF algorithm was only 0.025% with the training dataset, whereas the MLR and SVM algorithms yielded relatively higher values at 0.029% and 0.110%, respectively. These findings highlight the presence of a nonlinear relationship in predicting the SOM content, which the RF algorithm effectively captures. This approach offers accurate predictions of the SOM content, supporting sustainable agricultural land management through rapid and easy quantification.

Soil microbes from conservation agriculture systems reduce growth of Bt-resistant western corn rootworm larvae

Sustainable agricultural management practices aimed at improving soil health can alter the soil microbiome, which can influence plant health and defenses against insects. The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is a major belowground pest of corn. Pest management relies heavily on the planting of transgenic crops expressing Bacillus thuringiensis (Bt) toxins. In this study, we ask how corn-WCR interactions via the soil microbiome are affected by a conservation management system (extended corn-soybean-wheat rotation with cover crops under no-till) compared with a conventional management system (corn-soybean rotation under mulch tillage and no cover crops) when combined with transgenic Bt corn. To do this, we applied soil microbes from the conservation and conventional management systems to two corn lines, one producing Bt and one non-Bt. We then reared Bt-resistant and Bt-susceptible WCR on inoculated seedlings to examine plant and insect changes in fitness. We found that Bt was effective against susceptible larvae in both soil treatments. Bt-resistant larvae were ~ 20% smaller when reared in the presence of soil microbes from the conservation management system. Thus, control of Bt-resistant WCR may be improved in a conservation system without sacrificing Bt effectiveness in susceptible insects. Comparing the microbial communities using 16S rRNA sequencing revealed that management practices influenced the microbiomes associated with the soil and the plant rhizosphere, but not WCR. Our findings suggest value for growers in utilizing conservation management practices, such as no-till and cover crops, in agricultural systems through bottom-up changes to plant–insect interactions via the soil microbiome.