Promote Crop Growth Research Articles

Elemental sulfur effects on salt leaching, plant growth, nutrient uptake, and microbial diversity in an arid saline soil

The amendment of salt-affected soils with elemental sulfur (S0) has been recognized for its potential to effectively reduce soil salinity and pH, thereby enhancing soil physicochemical properties, promoting crop growth, and improving yields. Despite these known benefits, the widespread adoption of S0 for managing saline soils, particularly in arid calcareous regions, remains limited. Consequently, this study aimed to evaluate the impact of S0 on salt leaching, soil pH, nutrient uptake, plant growth, microbial diversity, and community structure under alkaline saline soil conditions. The study includes three main experiments: a preliminary column experiment without plants, a field trial with Rhodes grass (Chloris gayana), and a greenhouse pot experiment with wheat (Triticum spp.). Our findings demonstrated that S0 incorporation into the soil exerted a positive influence, resulting in increased salt removal, reduced soil pH, and improved plant growth. Specifically, soil amendment with 750 kgS0ha−1 led to a substantial salt removal, exceeding double in the column experiment, approximately 91.3 % in the field trial, and about 34.1 % in the greenhouse pot experiment compared to the control. S0 amendment also significantly lowered soil and leachate pH in both field and greenhouse trials, with reductions of 3.3 % and 6.3 %, and 8.1 % and 4.4 %, respectively, relative to the control. Calcium and phosphorus uptake by Rhodes grass increased significantly by 75 % and 14 %, respectively, compared with the control. Soil organic matter content significantly increased from 0.6 % to 1.5 % compared to that of the control. This overall enhancement in soil conditions resulted in a considerable increase in Rhodes grass and wheat yields by 13 % and 59 %, respectively. While the prokaryotic diversity (16S V4 rRNA sequencing) in the Rhodes grass field trial was not significantly affected by S0 amendments after two months, the microbial community composition showed remarkable differences between the S0-amended and control samples. Eighty-three unique taxa were exclusively found in the S0-amended samples. In conclusion, our findings suggest that the amendment of soil with S0 is a promising strategy for the sustainable management of calcareous salt-affected soils in arid regions.

Assessment of potentially hazardous elements in soils of the Boyacá industrial corridor (Colombia) using GIS, multivariate statistical analysis, and geochemical indexes

In the industrial corridor of Boyacá, Colombia, population growth is accompanied by anthropogenic activities such as industrial operations, vehicle exhaust fumes, mining, smelting, atmospheric deposition, and excessive use of chemical products to promote crop growth. These activities are known to have a significant impact on urban and rural soils, contributing significantly to elevated concentrations of potentially hazardous elements in the environment. This industrial corridor is an area of economic and social development that needs to provide reference information that will allow us to know the state of soil quality to preserve and manage the public and geoenvironmental health of this region. Anthropogenic activities have contributed to the accumulation of potentially hazardous elements in the environment, affecting various levels of life and creating risks with economic and social implications. However, igneous activity or detrital deposition also enriches soils and creates geochemical anomalies in specific locations. In these cases, the identification of potentially hazardous elements involves the determination of likely sources of contamination and their relationship to the geological setting. In this study, the concentrations of As, Cd, Pb, Mn, Fe, Zn, Hg, Cu and Ni were determined in eighty-one soil samples from the Boyacá industrial corridor (Colombia). The sequential trend of the concentrations of potentially hazardous elements was as follows: Fe > Mn > Zn > Ni > Cu> Pb > As > Cd > Hg. Furthermore, the application of spatial analysis criteria in GIS software with multivariate statistical tools and geochemical indices allowed the identification of anthropogenic and geogenic sources. Most of the potentially hazardous elements were found in soils exposed to industrial and agricultural activities, except for iron. This element showed low variability in all samples, regardless of the geological formations. Due to the lack of reference values for potentially hazardous elements in Colombia, the concentrations were compared with the environmental standards of the Environmental Protection Agency (EPA) and the Ecuadorian Ministry of Environment, Water and Ecological Transition (MAE). The results demonstrate the complexity of the soil and represent the first exploratory study of potentially hazardous elements in this industrial corridor. These results are the starting point for the establishment of geochemical background lines in Colombia and for inspection policies for areas where productive activities converge.

Potential of a novel endophytic diazotrophic Serratia sp. Wed4 for pyrene biodegradation

Endophytic diazotrophic Serratia sp. Wed4 with high nitrogenase activity (1260.9 ± 8.3 nmol C2H4 mL−1h−1) was isolated from Glycine max Linn growing in PAH contaminated soil for improving PAH removal and crop growth. Strain Wed4 biodegraded 37.0% of pyrene within 14 d via phthalate pathway in vitro and could biodegraded other PAHs with 2–5 rings effectively. Its capabilities on promoting crop growth included indole acetic acid (IAA) production (30.8 ± 3.3 μg mL−1), iron carrier production (A/Ar = 0.841 ± 0.002), inorganic phosphate dissolution (D/d = 1.184 ± 0.032) and organic phosphate dissolution (D/d = 1.154 ± 0.025). Strain Wed4 successfully colonized in barley tissues (>104 CFU g−1 FW), significantly promoted barley growth and nitrogen nutrition, reduced pyrene residues especially in shoots. Under sufficient nitrogen condition, strain Wed4 significantly promoted the dry weight of barley by 18.9%–33.9%, and decreased the pyrene residues by 46.4% in shoots and by 32.1% in roots. Meanwhile, under the deficient nitrogen condition, strain Wed4 significantly promoted the dry weight of barley by 40.1%–63.3% and decreased the pyrene residues by 39.0% in shoots and by 28.0% in roots. The pyrene contents were significantly negatively correlated with the total nitrogen contents in barley tissues, suggesting that nitrogen fixation of strain Wed4 also stimulated the pyrene removal. Based on its performance, Serratia sp. Wed4 provided a great potential to increasing crop yield and reducing PAH pollution in nitrogen deficient soils.

Ground Cover Rice Production System Affects Soil Water, Nitrogen Dynamics and Crop Growth Differentially with or without Climate Stress.

The ground cover rice production system (GCRPS) has been proposed as a potential solution to alleviate seasonal drought and early low-temperature stress in hilly mountainous areas; clarifying its impact on crop growth is crucial to enhance rice productivity in these areas. A two-year (2021-2022) field experiment was conducted in the hilly mountains of southwest China to compare the effects of the traditional flooding paddy (Paddy) and GCRPS under three different nitrogen (N) management practices (N1, zero-N fertilizer; N2, 135 kg N ha-1 as a urea-based fertilizer; and N3, 135 kg N ha-1 with a 3:2 base-topdressing ratio as urea fertilizer for the Paddy or a 1:1 basal application ratio as urea and manure for GCRPS) on soil water storage, soil mineral N content and crop growth parameters, including plant height, tiller numbers, the leaf area index (LAI), aboveground dry matter (DM) dynamics and crop yield. The results showed that there was a significant difference in rainfall between the two growth periods, with 906 mm and 291 mm in 2021 and 2022, respectively. While GCRPS did not significantly affect soil water storage, soil mineral N content, and plant height, it led to a reduction in partial tiller numbers (1.1% to 31.6%), LAI (0.6% to 20.4%), DM (4.4% to 18.8%), and crop yield (7.4% to 22.0%) in 2021 (wet year) compared to the Paddy. However, in 2022 (dry year), GCRPS led to an increase in tiller numbers (13.7% to 115.4%), LAI (17.3% to 81.0%), DM (9.0% to 62.6%), and crop yield (2.9% to 9.2%) compared to the Paddy. Structural equation modeling indicated that GCRPS significantly affected tiller numbers, plant height, LAI, DM, and productive tiller numbers, which indirectly influenced crop yield by significantly affecting tiller numbers and productive tiller numbers in 2022. Overall, the effects of GCRPS on soil water and N dynamics were not significant. In 2021, with high rainfall, no drought, and no early, low-temperature stress, the GCRPS suppressed crop growth and reduced yield, while in 2022, with drought and early low-temperature stress and low rainfall, the GCRPS promoted crop growth and increased yield, with tiller numbers and productive tiller numbers being the key factors affecting crop yield.

MAE-NIR: A masked autoencoder that enhances near-infrared spectral data to predict soil properties

Soil available nutrients are crucial for promoting crop growth, and controlling their content is essential for increasing yield, promoting smart agriculture, and protecting the environment. Near-infrared spectroscopy technology enables the efficient and nondestructive detection of soil nutrient content in real time. However, current near-infrared spectroscopy datasets suffer from data isolation due to the inability to share data feature advantages, necessitating expensive data acquisition. To address this issue, we propose an unsupervised method for near-infrared spectral enhancement to analyse soil samples from the red soil of southern Anhui. Our proposed framework, named MAE-NIR, is a near-infrared spectral masked autoencoder that learns highly robust and generic spectral features from abundantly available public near-infrared spectral datasets. We collected near-infrared spectroscopy data from a depth of 900–1700 nm and utilized the publicly available spectral dataset LUCAS 2009 to reconstruct the spectral waveform details. This method facilitates the capture of both local and global aspects, thereby aiding subsequent downstream tasks. Several renowned regressors, such as partial least squares regression, random forest, and neural networks, are also employed to assess the effectiveness of near-infrared spectral enhancement using MAE-NIR. The spectral enhancement method based on the masked autoencoder significantly outperforms all other spectral preprocessing methods. The coefficient of determination (R2) values of the best models of available nitrogen, phosphorus, and potassium in the soil increased to 0.941, 0.926, and 0.903, respectively, which are on average 22.42%, 11.14%, and 10.35% higher than those obtained from the previous best preprocessing methods. This indicates the efficacy of using MAE-NIR to predict soil nutrients, as it effectively enhances the accuracy of nutrient content measurements.

Synthesis and application of a compound microbial inoculant for effective soil remediation.

Currently, there is a noticeable scarcity of applications that harness composite microbial inoculants to stimulate straw decomposition, nitrogen fixation, and crop growth. This study addresses this gap by selecting and coculturing three bacterial strains to create a composite microbial inoculant named HY-1. This innovative inoculant exhibits multifunctional capabilities, including nitrogen fixation, straw decomposition, and crop growth promotion. Furthermore, we aimed to explore its impact on soil microbial communities. The results showed that the optimal preparation conditions for the compound microbial inoculant HY-1 were 28.5 ± 0.6°C, pH = 7.34 ± 0.40, and bacteriophage ratio 1:2:1 (Microbacterium: Streptomyces fasciatus: Bacillus amyloliquefaciens). Compared to single strains, the combination exhibited higher levels of cellulose-degrading and nitrogen-fixing enzyme activity, increased the straw degradation rate by 37.91% within 180days, and significantly promoted the growth of corn seedlings. Under the condition of straw return, the compound bio-fungicide HY-1 effectively improved the soil microbial diversity. At that time, the soil had the highest number of unique bacterial operational taxonomic units (166), and the abundance of Proteobacteria in the soil increased by 7.24%, while that of Acidobacteriota decreased by 2.27%. The biosynthetic function of the cell wall/membrane/periplasm and the metabolic function of transporting inorganic ions were significantly enhanced. In this study, we discovered that employing coculturing techniques to produce the composite microbial inoculant HY-1 and applying it in the field effectively compensates for the limitations of single-strain inoculants, which often exhibit fewer functions and less pronounced effects. This approach demonstrates significant potential for enhancing the quality of agricultural soils.

Porous fiber materials can alleviate the risk of farmland drought and flooding disasters and prompt crop growth.

Floods and droughts on farmland seriously damage agricultural production. Porous fiber materials (PFM) made from mineral rocks have high porosity, permeability, and water retention and are utilized widely in green roofs and agricultural production. Therefore, studying the impact of PFM on the improvement of farmland is of great importance for soil and water conservation. We set 64 extreme rainfalls to analyze the impact of PFM on soil water content (SWC), runoff, nutrient loss, microorganism, and plant growth. The results showed that PFM can effectively reduce runoff and improve soil water distribution, and enhance the soil water holding capacity. Furthermore, PFM reduced the loss of nitrogen and phosphorus by 18.3% to 97% in the runoff, and the soil erosion of summer corn was more strongly influenced by lower vegetation cover, compared with winter wheat. Finally, when PFM was buried in the soil, the wheat yield increased by -6.7%-20.4%, but the corn yield in some PFM groups decreased by 5.1% to 42.5% under short-duration irrigation conditions. Our study emphasizes that the effectiveness of PFM depends mainly on the following: First, PFM with high porosity can increase soil water holding capacity and timely replenish the water lost from the surrounding soil. Second, PFM with high permeability can increase infiltration during rainfall and decrease runoff and nutrient loss, reducing the risk of farmland flooding and pollution. Finally, PFM consists of gold ions and alkali metal oxides, which can stabilize agglomerates and improve soil enzyme activity, thereby increasing the relative abundance of some microbial strains and promoting crop growth. However, when the rainfall amount was low or PFM volume was large, PFM could not store water sufficiently during rainfall, which seriously reduced the maximum saturated moisture content and water absorption performance. Meanwhile, the PFM could not release water in time and replenish the soil water deficit, which increased drought risk. In conclusion, the appropriate volume of PFM and irrigation system may enhance soil water storage capacity, minimize agricultural pollution, and promote crop production.

Effect of Foliar Application of Silicon and Selenium on the Growth, Yield and Fruit Quality of Tomato in the Field

Tomato (Solanum lycopersicon) is a widely produced and consumed fruit vegetable worldwide. Silicon (Si) and selenium (Se) can promote crop growth and development. However, the effects of these elements on tomato fruit quality have not been investigated comprehensively, nor are their combined effects on yield and quality clear. The aim of this study was to investigate the effects of foliar application of Si and Se on tomato growth, yield and fruit quality. The tomato plants were foliarly applied with 1 mM Si and 25 μM Se individually or in combination, and the experiment was carried out in a plastic arch shed at Yangling in spring. Our results demonstrated improved plant growth by application of Si and Se, with the effect of combined treatment being more obvious. Application of Si individually or in combination with Se increased the yield. Se addition increased the concentrations of soluble sugars, vitamin C, phenols, anthocyanin, lycopene, carotenoids, Se and protein, and decreased the nitrate level, but did not affect the concentration of total organic acids in the fruit. Si application induced similar changes to Se addition in the levels of sucrose and protein in the fruit, but had no effect on other quality traits. The combined Si and Se treatment did not show significant superior effects on the fruit quality over their individual applications. Our results suggest that Si and Se application improved the tomato plant growth. Si and Se application, respectively, had obvious effects in the yield increase and quality improvement, and the combined treatment had positive effects on both aspects. The study may provide a theoretical base for the application of Se and Si fertilizers in tomato production.

Microbial inoculants with higher capacity to colonize soils improved wheat drought tolerance.

Microbial inoculants have gained increasing attention worldwide as an eco-friendly solution for improving agriculture productivity. Several studies have demonstrated their potential benefits, such as enhanced resistance to drought, salinity, and pathogens. However, the beneficial impacts of inoculants remain inconsistent. This variability is attributed to limited knowledge of the mechanisms by which microbial inoculants affect crop growth and a lack of ecological characteristics of these inoculants that limit our ability to predict their beneficial effects. The first important step is believed to be the evaluation of the inoculant's ability to colonize new habitats (soils and plant roots), which could provide crops with beneficial functions and improve the consistency and efficiency of the inoculants. In this study, we aimed to investigate the impact of three microbial inoculants (two bacterial: P1 and P2, and one fungal: P3) on the growth and stress responses of three wheat varieties in two different soil types under drought conditions. Furthermore, we investigated the impact of microbial inoculants on soil microbial communities. Plant biomass and traits were measured, and high-throughput sequencing was used to characterize bulk and rhizosphere soil microbiomes after exposure to drought stress. Under drought conditions, plant shoot weight significantly increased (11.37%) under P1 treatments compared to uninoculated controls. In addition, total nitrogen enzyme activity increased significantly under P1 in sandy soil but not in clay soil. Importantly, network analyses revealed that P1, consisting of Bacillus paralicheniformis and Bacillus subtilis, emerged as the keystone taxa in sandy soil. Conversely, P2 and P3 failed to establish as keystone taxa, which may explain their insignificant impact on wheat performance under drought conditions. In conclusion, our study emphasizes the importance of effective colonization by microbial inoculants in promoting crop growth under drought conditions. Our findings support the development of microbial inoculants that robustly colonize plant roots for improved agricultural productivity.

Combined resource utilization of ash from biomass power generation and wheat straw biochar for soil remediation

The lack of power resources leads to the rapid development of biomass power generation. Biomass power generation technology can not only rationally utilize biomass resources, but also alleviate energy crisis. But if this biomass ash is not handled properly, indiscriminate dumping can cause serious environmental problems such as dust, air and water pollution. The purpose of this study was to use the basic physical and chemical properties of biomass waste ash and biochar to evaluate the effects of mixed uses on soil pH、heavy metal remediation and plant growth. Plant growth was undertaken using ryegrass to examine the potential value of an ash-biochar mixture to ameliorate soil acidity and heavy metal pollution. The special fertilizer for rice was prepared by adding ammonium dihydrogen phosphate, potassium chloride, and urea to the ash and biochar. The results showed that the mixed use of ash and biochar could ameliorate soil acidification, reduce the absorption of cadmium and lead by the plants (43 % and 35 %, respectively), and promote plant growth. Determining of its total nutrients, soluble phosphorus, nitrate nitrogen, and particle size supported that it fell within the high concentration fertilizer range of the national standard for compound fertilizers. The special fertilizer can be used as high quality fertilizer to promote crop growth. In-depth research on the treatment and recycling of biomass power generation waste ash has an essential effect on reducing secondary environmental pollution and waste recycling .It can reduce random dumping, thereby reducing dust, air and water pollution. This was conducted to provide a reference for the preparation of soil amendments and to develop a better amendment and high-quality special fertilizer for rice with biomass waste ash and biochar.

Long-term fallowing produces specific fungal taxa associated with soil carbon storage

Cropland expansion has caused the loss of soil organic carbon (SOC) and the degradation of microbial communities. Fallowing is an important strategy for soil restoration, and fungi are critical in soil fertilization. This study compared the soil properties and fungal assemblage in two adjacent environments (farmland vs. fallowing) using a 30-year field experiment composed of five treatments: fallowing or agricultural management plus no fertilization, chemical fertilization, and chemical fertilization plus cow manure or crop straw amendments. The fallowed soil had more diverse fungi and maintained a higher SOC than the artificially managed treatments. Importantly, the relative abundance of Chaetomiaceae was positively correlated with all the carbon components (SOC, dissolved organic carbon, and microbial biomass carbon) simultaneously. An RNA-Seq of Trichocladium uniseriatum, the key fungus affiliated with Chaetomiaceae, showed that straw amendment significantly upregulated the genes for T. uniseriatum melanogenesis, resulting in recalcitrant necromass formation. A remarkable CO2 assimilation capacity of T. uniseriatum was revealed by 13C-labelling assay. Therefore, T. uniseriatum improved SOC storage directly by CO2 fixation and indirectly by melanogenesis. Fertilization of agricultural systems can stimulate the growth of T. uniseriatum. T. uniseriatum inoculation promoted crop growth, facilitating C absorption from the roots. This study highlighted that the valuable microbial species resources preserved in fallowed soils can improve farmland ecosystems.

A Review of Plastic Film Mulching on Water, Heat, Nitrogen Balance, and Crop Growth in Farmland in China

Plastic film mulching has been widely used to improve crop yield and water use efficiency, although the effects of plastic film mulching on water, heat, nitrogen dynamics, and crop growth are rarely presented comprehensively. This study investigated a large number of studies in film mulching fields from the past 10 years (mostly from 2019 to 2023) and summarized the impact of plastic film mulching, progress in modeling with film mulching, and future research directions. The effects of plastic film mulching were intricate and were influenced by film mulching methods, irrigation systems, crop types, crop growth stages, etc. Overall, plastic film mulching showed a positive effect on improving soil water, temperature, and nitrogen status, enhancing crop transpiration and photosynthetic rates, and promoting crop growth and yield, although film mulching may have negative effects, such as increasing rainfall interception, blocking water entering the soil, and reducing net radiation income. The crop yield and water use efficiency could increase by 39.9–84.7% and 45.3–106.4% under various film mulching methods. Coupled models of soil water and heat transport and crop growth under plastic film mulching conditions have been established by considering the effects of plastic film mulching on the upper boundary conditions of soil water and heat, energy budget and distribution processes, and the exchange of latent and sensible heat between soil and atmosphere. The models have good applicability in film mulched farmland of maize, rice, and potato for different regions of China. Further development is needed for soil water, heat, nitrogen migration, and crop growth models under different plastic film mulching methods, and the acquisition of soil and crop indicators under plastic film mulching conditions based on big data support. The study will provide reference for the subsequent development and innovation of plastic film mulching technology.

Effects of Interaction of Protein Hydrolysate and Arbuscular Mycorrhizal Fungi Effects on Citrus Growth and Expressions of Stress-Responsive Genes (Aquaporins and SOSs) under Salt Stress.

Protein hydrolysates (PHs) and arbuscular mycorrhizal fungi (AMF) are environmentally friendly biostimulants that effectively promote crop growth and alleviate the damage from abiotic stress. However, the physiological and molecular regulatory mechanisms are still unclear. This study aimed to explore the effects of PHs and AMF on growth, mineral nutrient absorption, and expression of Aquaporins and SOSs in Goutoucheng (Citrus aurantium) under salt stress. Results showed that PH application and AMF inoculation significantly promoted plant growth and enhanced mineral element absorption and sodium effluxion in citrus under salt stress. The biomass, root activity, leaves mineral nutrition contents in PHs, AMF, and combined (PHs and AMF) treatments were significantly higher than those of control. Leaves sodium content in three treatments was significantly lower than in the control. AMF and combined treatments showed dominant effects than PHs alone. Besides, PHs interacted with AMF on growth, nutrient absorption, and sodium effluxion. Importantly, AMF and PHs induced stress-responsive genes. PIP1, PIP3, SOS1, and SOS3 expression in PHs and AMF treatments was significantly higher than control. Thus, it was concluded that AMF and PHs enhanced the salt tolerance of citrus by promoting nutrient absorption and sodium effluxion via up-regulating the expression of PIPs and SOSs. The mixed application of PHs and AMF had a better effect.

Effects of temporal and spatial scales on soil yeast communities in the peach orchard.

Shihezi Reclamation Area is located at the southern edge of the Junggar Basin, with natural, soil, and climatic conditions unique to the production of peaches. In turn, peach orchards have accumulated rich microbial resources. As an important taxon of soil fungi, the diversity and community structure changes of yeast in the soil of peach orchards on spatial and temporal scales are still unknown. Here, we aimed to investigate the changes in yeast diversity and community structure in non-rhizosphere and rhizosphere soils of peach trees of different ages in the peach orchard and the factors affecting them, as well as the changes in the yeast co-occurrence network in the peach orchard at spatial and temporal scales. High-through put sequencing results showed that a total of 114 yeast genera were detected in all soil samples, belonging to Ascomycota (60 genera) and Basidiomycota (54 genera). The most dominant genus, Cryptococcus, was present in greater than 10% abundance in each sample. Overall, the differences in yeast diversity between non-rhizosphere and rhizosphere soil of peach trees at 3, 8 and 15 years were not significant. Principal coordinate analysis (PCoA) showed that differences in yeast community structure were more pronounced at the temporal scale compared to the spatial scale. The results of soil physical and chemical analysis showed that the 15-year-old peach rhizosphere soil had the lowest pH, while the OM, TN, and TP contents increased significantly. Redundancy analysis showed that soil pH and CO were key factors contributing to changes in soil yeast community structure in the peach orchard at both spatial and temporal scales. The results of co-occurrence network analysis showed that the peach orchard soil yeast network showed synergistic effects as a whole, and the degree of interactions and connection tightness of the 15-year-old peach orchard soil yeast network were significantly higher than the 3- and 8-year-old ones on the time scale. The results reveal the distribution pattern and mechanism of action of yeast communities in peach orchard soils, which can help to develop effective soil management strategies and improve the stability of soil microecology, thus promoting crop growth.

Mobile robotics in smart farming: current trends and applications.

In recent years, precision agriculture and smart farming have been deployed by leaps and bounds as arable land has become increasingly scarce. According to the Food and Agriculture Organization (FAO), by the year 2050, farming in the world should grow by about one-third above current levels. Therefore, farmers have intensively used fertilizers to promote crop growth and yields, which has adversely affected the nutritional improvement of foodstuffs. To address challenges related to productivity, environmental impact, food safety, crop losses, and sustainability, mobile robots in agriculture have proliferated, integrating mainly path planning and crop information gathering processes. Current agricultural robotic systems are large in size and cost because they use a computer as a server and mobile robots as clients. This article reviews the use of mobile robotics in farming to reduce costs, reduce environmental impact, and optimize harvests. The current status of mobile robotics, the technologies employed, the algorithms applied, and the relevant results obtained in smart farming are established. Finally, challenges to be faced in new smart farming techniques are also presented: environmental conditions, implementation costs, technical requirements, process automation, connectivity, and processing potential. As part of the contributions of this article, it was possible to conclude that the leading technologies for the implementation of smart farming are as follows: the Internet of Things (IoT), mobile robotics, artificial intelligence, artificial vision, multi-objective control, and big data. One technological solution that could be implemented is developing a fully autonomous, low-cost agricultural mobile robotic system that does not depend on a server.

Soil Disturbing Agent-Creation and Application of “G15” Series Products

Diseases caused by two or more soil-borne pathogens are called compound soil-borne diseases. We have pioneered the "root splitter" and the imaging analysis system, providing a new tool for studying compound soil-borne diseases and a new method for evaluating crop resistance and pesticide (fertilizer) efficacy, and laying a foundation for the development of microbial agents, pesticides, and fertilizers. On this basis, we have developed a range of soil-borne disease disturbance agents “G15”, including a series of bio-organic fertilizers, liquid fertilizers and immune inducers. a) Microecological control series of bio-organic fertilizer: a new method of strain culture and classification screening based on the information of main components of organic fertilizer materials was used to obtain strains with high matching degree with organic materials. Then the process optimization technology was renewed by the ferulic acid rapid detection system. Through the 2-hour rapid detection and 30-day rapid optimization, the qualification rate of products is over 95%. It also standardized the basic operation methods and application doses for different crops and different application methods, and stabilized the application effect of products. The application of bioorganic fertilizers significantly reduced the abundance of pathogenic fungi and bacteria in the soil, and significantly inhibited the development of Solanaceae and Cucurbits wilt in the field (Figure 1A & 1B). b) Liquid fertilizer series products: liquid fertilizer with large, medium and trace elements, including nanometer silicon, ionic boron, ionic calcium, macroelement water-soluble fertilizer etc, which can improve crop quality and yield, increase disease resistance. We found that nano-silicon, ionic boron and ionic calcium can significantly promote the growth and disease resistance of grape (Figure 2). c) Salicylic Acid (SA), an immune inducer product, can improve the microbiological structure of soil by flushing with basic fertilizer; Foliar spraying can promote the expression of crop resistance genes, enhance the ability of drought resistance, salt resistance, oxidation resistance and heavy metal resistance, and improve the stress resistance and disease resistance of crops; Soaking or spraying can store the harvested fruits and keep them fresh; Combined with liquid fertilizer series products, crops can be put on the market early. However, SA is a natural product widely used in the plant kingdom and has a wide range of regulatory effects on plant resistance and growth. SA is slightly soluble in water and easily soluble in ethanol, ether and chloroform, so the concentration of SA solution is currently limited and the highest concentration can reach only 8%. Therefore, the concentration of SA and a higher proportion of ethanol in the solution limit the wide use of SA solution. In this study, we added willow bark to an aqueous solution containing PH 2.0-3.5 and soaked it at room temperature under the action of ultrasound and electrostatic field, which promoted the dissolution of water-soluble components and inhibited the dissolution of SA. After filtering the aqueous solution, polyethylene glycol was added to increase the solubility of SA, and finally the SA solution with a concentration of more than 12% was obtained. In order to verify the effect of the high content of SA on improving crop yield and ripening. We applied the leaf spray method to immature tomatoes in the field. The results showed that the total weight of 30 tomatoes in the treatment group was 7.4 kg, while in the control group it was 5.55 kg, an increase of 32.97%. The tomatoes in the treatment group were red in a wide range and reached the level of natural ripeness, while the tomatoes in the control group were cyan in a wide range and were not yet ripe. In addition, the average sugar content of tomatoes in the treatment group was 7.33, while it was 5.85 in the control group (Figure 3). The results suggest that spraying with a highly concentrated SA solution before flowering and harvesting can increase the yield and sweetness of tomatoes, adjust the uniform ripening time of tomatoes, effectively reduce tomato cultivation obstacles and harvesting costs, and improve the benefits of cultivation. Therefore, in order to prevent and control the compound soil-borne diseases caused by multiple soil-borne pathogens, we proposed a combination of bio-organic fertilizers, liquid fertilizers with large, medium and trace elements and immune inducers to regulate the composition of soil microbial community, improve the soil ecological environment and promote crop growth to comprehensively control the compound soil-borne diseases.

Enhancing the Effectiveness of Soil Amendments Using Anionic Polyacrylamide: A Review

The loss of soil amendments in plains and sloped locations with runoff water is a crucial problem. The diminution in the residence period of soil amendments in the soil affects their effectiveness. Due to non-cohesive character, most of the soil amendments such as biochar, lime, sulphur etc. erode with the soil on sloped surfaces. Ultimately, soil productively remains same before and after the application of soil amendments, which causes loss of time, money and labor. As per the available literatures, it was demonstrated that soil amendments must be applied with any cohesive ingredient in order to maximize their effects. Despite having a cohesive nature, gypsum has also been found to be disappearing from the field. An inexpensive, easily accessible, adaptable, and organic soil additive called anionic polyacrylamide (PAM) can be utilised to address these issues. PAM does not directly contribute to the growth of vegetation, but because of its organic and cohesive character, it gives significant stability to other soil amendments and promotes crop growth. In this review, the efficacy of biochar, gypsum, lime, and PAM is discussed both singly and in combination. Most importantly, effect of blending of important soil amendments such as biochar, gypsum and lime with the PAM was discussion to understand biomass growth, soil erosion, nutrient loss and enhancement of soil properties to promote soil productivity.

Nitrate sources and transformation processes in groundwater of a coastal area experiencing various environmental stressors

In coastal salinized groundwater systems, contamination from various nitrate (NO3) inputs combined with complex hydrogeochemical processes make it difficult to distinguish NO3 sources and identify potential NO3 transformtation processes. Effective field-based NO3 studies in coastal areas are needed to improve the understanding of NO3 contamination dynamics in groundwater of such complex coastal systems. This study focuses on a typical Mediterranean coastal agricultural area, located in Tunisia, experiencing substantial NO3 contamination from multiple anthropogenic sources. Here, multiple isotopic tracers (δ18OH2O, δ2HH2O, δ15NNO3, δ18ONO3, and δ11B) combined with a Bayesian isotope MixSIAR model are used (i) to identify the major NO3 sources and their contributions, and (ii) to describe the potential NO3 transformation processes. The measured NO3 concentrations in groundwater are above the natural baseline threshold, suggesting anthropogenic influence. The measured isotopic composition of NO3 indicates that manure, soil organic matter, and sewage are the potential sources of NO3, while δ11B values constrain the NO3 contamination to manure; a finding that is supported by the results of MixSIAR model revealing that manure-derived NO3 dominates over other likely sources. Nitrate derived from manure in the study area is attributed to organic fertilizers used to promote crop growth, and livestock that deposit manure directly on the ground surface. Evidence for ongoing denitrification in groundwaters of the study area is supported by an enrichment in both 15N and 18O in the remaining NO3, although isotopic mass balances between the measured and the theoretical δ18ONO3 values also suggest the occurrence of nitrification. The simultaneous occurrence of these biogeochemical processes with heterogeneous distribution across the study area reflect the complexity of interactions within the investigated coastal aquifer. The multiple isotopic tracer approach used here can identify the effect of multiple NO3 anthropogenic activities in coastal environments, which is fundamental for sustainable groundwater resources management.

Impact of Precision Nutrient Management on Rice Growth and Productivity in Southern Odisha

Background: Despite the emergence of numerous smart tools in recent times, a significant research gap still exists in identifying the most effective smart tool that optimally synchronizes fertilizer application with crop requirements, thereby promoting crop growth and productivity in accordance with the principles of SSNM. Methods: The present investigation took place at the PG Experimental Farm, MSSSoA, CUTM, Odisha, during the boro season of 2021-22.The experiment followed a randomized block design, with eleven treatments that were replicated three times. The investigated treatments included the following: T1-absolute control (no fertilizer), T2-75% of the recommended dose of fertilizer (RDF), T3-100% RDF, T4-125% RDF, T5-75% RDF followed by a spray of nano urea at a rate of 2ml/L during panicle initiation, T6-100% RDF followed by a spray of nano urea at a rate of 2ml/L during panicle initiation, T7- leaf colour chart (LCC) 3 based nitrogen management,, T8-LCC 4 based nitrogen management, T9- Sufficiency Index (SI)-based nitrogen management at SI less than 90%, T10- Nutrient expert (NE)-based nutrient recommendation, and T11- Rice crop manager (RCM)-based nutrient recommendation. Result: The study found that implementing nitrogen management based on site-specific information, using a total of 150 kg of nitrogen per hectare applied in four separate applications (at the basal stage, 28 days after transplanting, 42 days after transplanting, and 63 days after transplanting), along with consistent levels of phosphorus and potassium, led to a 16.68% increase in grain yield and a 13.17% increase in biological yield for rice. This approach outperformed the traditional method of applying 100% recommended dose of fertilizer with 120 kg of nitrogen at fixed time intervals (basal, active tillering, and panicle initiation).

Earthworm activity effectively mitigated the negative impact of microplastics on maize growth

Microplastic pollution can have detrimental effects on soil environments and inhibit crop growth. Earthworms, known as soil engineers, promote crop growth, but their role and impact on the amelioration of microplastic-polluted soil is not yet clear. In this study, we investigated the impact and pathways of earthworm activity on microplastic-contaminated soil by introducing varying densities (without earthworm:0, low-density: 1, medium-density: 2, high-density: 5 ind column−1) of earthworms (epi-endogeic) into soil contaminated with two types of microplastics: polyethylene and polyvinyl chloride. Our results showed that earthworms all survived in soil polluted with two types of microplastics. Meanwhile, earthworm activity increased nutrient content and enzyme activity by 0.2–36.1% and 2.9–34.3%, respectively, and significantly increased soil microbial biomass and community diversity index. Earthworm activity also decreased antioxidant enzyme activity and promoted maize plant growth, including agronomic traits such as plant height, biomass, root length, and root surface area. Furthermore, the nutrient content of maize organs increased by 1.1–29.7%. Partial least squares models confirmed that earthworm activity alleviated the stress effect of microplastic pollution on plant growth by improving soil structure, fertility, and microbial abundance and diversity. The greatest effect on maize growth was observed with the improvement of soil physical-chemical properties. Our results suggest that medium densities of earthworms have the greatest soil improvement effect and provide an important basis for bioremediation of farmland contaminated by microplastics and promoting green and efficient development in agriculture.