Agronomic Applications Research Articles

Computational identification and characterization of chitinase 1 and chitinase 2 from neotropical isolates of Beauveria bassiana

BackgroundThe fungus Beauveria bassiana is widely used for agronomical applications, mainly in biological control. B. bassiana uses chitinase enzymes to degrade chitin, a major chemical component found in insect exoskeletons and fungal cell walls. However, until recently, genomic information on neotropical isolates, as well as their metabolic and biotechnological potential, has been limited.MethodsEight complete B. bassiana genomes of Neotropical origin and three references were studied to identify chitinase genes and its corresponding proteins, which were curated and characterized using manual curation and computational tools. We conducted a computational study to highlight functional differences and similarities for chitinase proteins in these Neotropical isolates.ResultsEleven chitinase 1 genes were identified, categorized as chitinase 1.1 and chitinase 1.2. Five chitinase 2 genes were identified but presented a higher sequence conservation across all sequences. Interestingly, physicochemical parameters were more similar between chitinase 1.1 and chitinase 2 than between chitinase 1.1 and 1.2.ConclusionChitinases 1 and 2 demonstrated variations, especially within chitinase 1, which presented a potential paralog. These differences were observed in their physical parameters. Additionally, CHIT2 completely lacks a signal peptide. This implies that CHIT1 might be associated with infection processes, while CHIT2 could be involved in morphogenesis and cellular growth. Therefore, our work highlights the importance of computational studies on local isolates, providing valuable resources for further experimental validation. Intrinsic changes within local species can significantly impact our understanding of complex pathogen-host interactions and offer practical applications, such as biological control.

An interdisciplinary overview on biochar production engineering and its agronomic applications

Biochar is a porous, carbon-rich material derived from the thermochemical decomposition of biomass materials. Biochars are suitable soil amendments that enhance soil properties and improve crop productivity. Biochar agronomic impact in soils depends on its physiochemical properties. Recent research has shown that feedstock type and pyrolysis temperature are the key factors influencing biochar physiochemical properties. However, an in-depth understanding of the biochar-soil-plant co-relationship governing biochar agronomic performance still needs improvement. A comprehensive overview of the effect of biomass and pyrolysis temperature on biochar properties, mechanisms governing biochar-soil interactions impact on agronomic indices, the long-term effect of biochar, and the viability of large-scale biochar agricultural systems have been discussed. The mechanisms governing the impact of temperature and biomass properties on biochar agronomic properties are different for low temperature (<500 °C) and high temperature (>500 °C). The agronomic benefits of biochar are dependent on biochar-soil-plant interaction mechanisms. The economic and financial feasibility of large-scale production of biochar is case-specific and makes business sense when all co-pyrolysis products are recovered and sold. Understanding biochar-soil-plant-climate interaction mechanisms is key to designing biochars to address specific agronomic needs and requires an interdisciplinary and multiscale approach. Future studies should focus on long-term co-relationships among biochar physiochemical properties, soil conditions, climate, and farm management.

Bone char: characterization and agronomic application as an alternative source of phosphorus

ABSTRACT Alternative materials can be used to reduce reliance on mining for P-based fertilizers. In this sense, the pyrolysis process of bovine bones produces the “bone char”, which can be used as a source of P. This study aimed to characterize bone char and conduct a comparative analysis with both soluble (triple superphosphate) and non-soluble (Bayóvar phosphate rock) phosphate fertilizers, specifically examining its behavior in soil and uptake by plants. Bone char characterization was performed by X-ray diffraction (XRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and scanning electron microscopy coupled with energy-dispersive (SEM-EDS). The XRD analyses have shown the presence of hydroxyapatite in the bone char, bands assigned to P-O stretching from phosphate have been observed in ATR-FTIR, and Ca, P, C, and O elements were identified in the materials by EDS analyses. Solubility from fertilizer extractants was higher for bone char compared to Bayóvar, and both sources showed lower solubility compared to triple superphosphate. Cumulative amount of P released from bone char was higher than Bayóvar and lower than triple superphosphate. Amount of total dry matter, total shoot P uptake, and total shoot Ca uptake were higher for triple superphosphate compared to bone char and Bayóvar. Release profile of P from bone char strongly suggests this material can be used as a slow-release P source, with intermediate solubility between soluble and non-soluble commercialized sources.

A Search for Biologically Active Compounds for Potential Pharmaceutic and Agronomic Applications.

Summarized here are some aspects of my research activities in Ciba-Geigy Central Research Laboratories (1985-1996), in Novartis and Syngenta Crop Protection Research (1997-2020). I have followed the chronological order of these research activities covering only published data.

Overview of the Impact of Compost on Bulk Density, Aggregate Consistency and Cation Exchange Capacity of Soils and its Consequential Effect on Crop Productivity

Organic fertilizers offer several advantages over chemical fertilizers and are an environmentally friendly alternative that could help sustainably farmed land. Reviewing indigenous knowledge of the agronomic applications of organic manure and its possible contribution to agricultural growth was the goal of this article. It is evident that organic manures from various plant and animal sources can be used to satisfy certain field needs. However, the use of organic manures is still primarily conventional since they have not been well received by agricultural strategies. When bulky organic manures are directly applied to soil, they accelerate mineralization and reduce the rate at which nutrients, especially nitrogen, are released. Compared to raw resources, which have limited value and certain disadvantages, composting these wastes appears to offer significant potential. The majority of researchers verified that adding compost might enhance the soil's organic matter content, nutrient status, and physical, chemical, and biological properties. Soil organic matter concentrations rise in every long-term compost treatment study. But since they contain more stable carbon than fresh or immature composts, mature composts raise Soil organic matter considerably more effectively. Furthermore, because compost has so many beneficial effects on the physical, chemical, and biological aspects of soil, it helps to stabilize and improve crop quality and yield. As a result, the majority of studies have demonstrated that compost has an equalizing influence on seasonal and annual variations in soil temperature, air, water, and plant nutrient availability, as well as crop yields. mostly due to the nutrients' gradual release and availability in compost-combined fertilization techniques, which frequently yield positive outcomes. Therefore, composting can be a useful choice for building effective plant-nutrient management methods in many settings for sustainable agricultural systems within small-scale farming in impoverished nations.

Development of a Biodegradable Ternary Blend of Poly(vinyl alcohol) and Polyhydroxybutyrate Functionalized with Triacetin for Agricultural Mulch Applications.

The development of biodegradable mulch for agricultural applications represents a sustainable approach to reducing plastic pollution. Poly(vinyl alcohol) (PVA) is one of the nontoxic and biodegradable polymers that can be used as mulching film. However, a major drawback of PVA is its moisture sensitivity, which limits its applications. In this study, a biocomposite based on PVA and polyhydroxybutyrate (PHB), plasticized with triacetin, was developed by solvent casting method. The biocomposite film exhibited good mechanical properties, better integrity, reduced transmittance, and light-blocking properties, which can prevent weed growth. Additionally, an improvement in surface characteristics was observed, as demonstrated by the shift in contact angle from 44 to 99° and a reduction in the water vapor transmission rate (WVTR) from 4.82 to 2.31 g/h m2. For agronomic application, the developed films were experimentally applied as mulch for maize plants in pots. The results were positive, showing that the mulches effectively supported the growth of the maize plants. Further, signs of initial degradation were observed after 5 days, and the film reached a degradation level of 50-55% after 30 days under natural conditions. Thus, this work has provided new insights for expanding the application range of PVA films in biobased mulching materials.

CLI: A new protocol for the isolation of Lactic Acid Bacteria from complex plant samples

Lactic Acid Bacteria (LAB) are predominantly probiotic microorganisms and the most are Generally Recognized As Safe (GRAS). LAB inhabit in the human gut ecosystem and are largely found in fermented foods and silage. In the last decades, LAB have also has been found in plant microbiota as a new class of microbes with probiotic activity to plants. For this reason, today the scientific interest in the study and isolation of LAB for agronomic application has increased. However, isolation protocols from complex samples such as plant tissues are scarce and inefficient.In this study, we developed a new protocol (CLI, Complex samples LAB Isolation) which yields purified LAB from plants. The sensitivity of CLI protocol was sufficient to isolate representative microorganisms of LAB genera (i.e. Leuconostoc, Lactococcus and Enterococcus).CLI protocol consists on five steps: i) sample preparation and pre-incubation in 1% sterile peptone at 30 °C for 24–48 h; ii) Sample homogenization in vortex by 10 min; iii) sample serial dilution in quarter-strength Ringer solution, iv) incubation in MRS agar plates with 0.2% of sorbic acid, with 1% of CaCO3, O2 < 15%, at pH 5.8 and 37 °C for 48 h.; v) Selection of single colonies with LAB morphology and CaCO3-solubilization halo. Our scientific contribution is that CLI protocol could be used for several complex samples and represents a useful method for further studies involving native LAB.

Low-concentration repeated exposure and high-concentration single exposure of cyanamide suppressed the growth of redroot pigweed in the alfalfa field

The inclination toward natural products has led to the onset of the discovery of new bioactive metabolites that could be targeted for specific therapeutic or agronomic applications. Despite increasing knowledge coming to light of plant-derived materials as leads for new herbicides, relatively little is known about the mode of action on herbicide-resistant weeds. Cyanamide (CA) is a naturally occurring herbicide synthesized by hairy vetch (Vicia villosa Roth.). However, it has not been experimentally verified whether CA suppresses target plants via sustained discharge at low concentrations, as is often the case with most plant-derived materials. This study aimed to detect the toxicity and the mode of action of CA to alfalfa (Medicago sativa L.) and redroot pigweed (Amaranthus retroflexus L.). The toxicity of CA toward the alfalfa and redroot pigweed by three different exposure patterns was compared: low-concentration repeated exposure with 0.3 g/L CA (LRE), high-concentration single exposure with 1.2 g/L CA (HSE), and distilled water spray as control. The results showed that CA had a stronger inhibitory effect on redroot pigweed growth compared to alfalfa under both LRE and HSE exposure modes, with leaves gradually turning yellow and finally wilting. Beyond that, field trials were conducted to corroborate the toxicity of CA to alfalfa and redroot pigweed. The results have also shown that CA could inhibit the growth of redroot pigweed without significant adverse effects on alfalfa. The outcomes concerning electrolyte permeability, root activity, and malondialdehyde (MDA) content indicated that CA suppressed the growth of redroot pigweed by interfering with the structure of the cell membrane and impacting cellular osmotic potential. CA could destroy the cell membrane structure to inhibit the growth of the redroot pigweed by both LRE and HSE exposure modes, which provides a theoretical basis for preventing and controlling redroot pigweed in alfalfa fields.

Cactus pear pruning residue in agriculture: Unveiling soil-specific responses to enhance water retention

This study examines the effects of incorporating powdered cactus pear pruning waste (PCPPW) on the hydraulic properties of benchmark soils, in line with circular economy principles. The cultivation of cactus pear generates substantial amounts of pruning residues, which offer the potential for nutrient recovery and reuse. Our findings reveal that amending soils with this material has a positive impact on water retention, but it requires a substantial volume, exceeding 20%, which may not be practical for open-field applications. However, this presents promise for the horticultural and floricultural sectors. These results challenge previous assumptions about soil density, plant-available water capacity, and swelling potential, contributing to our understanding of agronomic applications. Notably, the enhancement of drainable water capacity is most significant in less clayey soils, while highly clayey soils experience fewer benefits. These results highlight the importance of considering specific soil conditions when implementing circular economy principles, particularly in soil amendment practices.

Epigenetics and plant hormone dynamics: a functional and methodological perspective.

Plant hormones, pivotal regulators of plant growth, development, and response to environmental cues, have recently emerged as central modulators of epigenetic processes governing gene expression and phenotypic plasticity. This review addresses the complex interplay between plant hormones and epigenetic mechanisms, highlighting the diverse methodologies that have been harnessed to decipher these intricate relationships. We present a comprehensive overview to understand how phytohormones orchestrate epigenetic modifications, shaping plant adaptation and survival strategies. Conversely, we explore how epigenetic regulators ensure hormonal balance and regulate the signalling pathways of key plant hormones. Furthermore, our investigation includes a search for novel genes that are regulated by plant hormones under the control of epigenetic processes. Our review offers a contemporary overview of the epigenetic-plant hormone crosstalk, emphasizing its significance in plant growth, development, and potential agronomical applications.

Identification of the physiological characteristics of some local Aceh rice (Oryza sativa L.) germplasms

The identification of local rice germplasms resources is essential for determining morphological and anatomical traits for agronomic applications. In this study, we have screened several local rice germplasms from Aceh, conducted in Gampong Paloh Lada and Agroecotechnology Laboratory, Agriculture Faculty, Universitas Malikussaleh, Aceh Utara Regency, from February to June 2023. The study employed Randomized Block Design Non-Factorial, consisting of 7 lines of local germplasms, including Unsyiah Cakep, Unsyiah Seumeulu, Cot Bada, Sigunca, Sigupai, Cot Bada and Rajasa (control). Flowering age, net assimilation rate, relative growth rate, root length, shoot – root ratio and 1000- grain weight was observed. The results of this study showed that there were significant differences between several rice strains on the variables of flowering age, net assimilation rate 40-20 DAP, relative growth rate 60-40, shoot-root-ratio at 60 DAP and harvest, root length, 1000 seed weight. Cotbada eight and Cotbada four strains gave the best effect compared to Rajasa (control) and other strains, seen in the parameters of relative growth rate two, number of grains per clump, weight of 1000 seeds and yield tonnes/ha. Cotbada four strain with a production of 7.24 tonnes/ha and followed by Cotbada eight strain with a yield of 6.48 tonnes/ha.

Microbial community assembly and chemical dynamics of raw brewers’ spent grain during inoculated and spontaneous solid-state fermentation

Solid-state fermentation (SSF) carried out by microbial bioinoculants is an environmentally friendly technology for the sustainable recovery and valorization of agri-food wastes. Particularly, mesophilic SSF processes allows the production of bio-organic fertilizers enriched with beneficial soil microorganisms. However, the establishment of microbial consortia and the interaction with native waste microbiota still require thoughtful investigations. Here, raw brewers’ spent grain (BSG), the main waste from the brewing industry, was subjected to two mesophilic SSF processes (maximum temperature of 35 °C) carried out by a multi-kingdom microbial bioinoculant and the BSG spontaneous microbiota. After 90 days, both SSF processes led to stable organic soil amendments, as indicated by the C:N ratio (10.00 ± 1.4), pH (6.66 ± 0.09), and DOC (8.45 ± 1.2 mg/g) values. Additionally, the fermented BSG showed a high nitrogen content (42.2 ± 3.4 mg/Kg) and biostimulating activities towardLepidium sativumseeds. The monitoring of microbial communities by high-throughput sequencing of 16S and ITS rRNA indicated that BSG samples were enriched in microbial genera with interesting agronomic applications (i.e.,Devosia, Paenibacillum, Trichoderma, Mucor, etc.). Microbial cross-kingdom network analyses suggested that the microbial assembly of BSG was significantly influenced by the bioinoculant, despite the inoculated microbial genera being able to persist in BSG samples only the first week of SSF. This suggests that the study of microbial interactions between exogenous microbial inoculants and waste resident microbiota is required to optimize SSF processes aimed at the recovery and valorization of unprocessed wastes.

Research and Possible Agronomic Applications of C60(OH)24 Adducts with Heavy Metals for Crop Treatment

This article describes the synthesis of fullerenol—C60(OH)24 adducts with some heavy metals—C60(ONa)x(O2Me)(24−x)/2;C60(ONa)x(O3Me)(24−x)/3; Me=Co; Cu; Mn; Zn; Gd; Tb. The identification of adducts was carried out by the methods of: elemental analysis, infrared and electronic spectroscopy, complex thermal analysis, high-performance liquid chromatography and dynamic light scattering. The solubility of adducts in aqueous solutions in the ambient temperature range has been studied. The solubility was significant and ranged from a few tenths to 1 g/dm3. The use of these adducts as micronutrients for spring barley crops in the Republic of Kazakhstan is considered. When using these nanopreparations, a general increase in yield (tens, up to 80 rel.%), nutrient content and moisture content of seeds (4–5 rel. mass %), as well as the resistance of the latter to the effects of pathogenic microorganisms (percentage of healthy seeds growth up to 10 rel.%), was noted.

Reclaiming phosphate from aqueous solution using biochar derived from anaerobically digested waste activated sludge and its potential as phosphate fertilizer

ABSTRACT A novel strategy for reclamation and reuse of phosphate from aqueous solution was developed using Mg-enriched biochar prepared from anaerobically digested sludge (ADBC). The ADBC pyrolyzed at 600°C (ADBC-600) exhibited the maximum phosphate removal capacity of 23.2 mg/g, which was much higher than that of raw sludge biocha (10.1 mg/g). Adsorption kinetic and isotherm experiments showed that the adsorption of phosphate on ADBC-600 could be well described by the pseudo-second-order model and Langmuir model, indicating that the adsorption was mainly dominated by chemisorption process. The postsorption characterization results suggested that Mg-induced precipitation was likely the main P adsorption mechanism by ADBC. Moreover, the spent biochar was re-utilized as an efficient phosphate fertilizer for improving wheat seed germination and growth. Provided a sustainable and eco-friendly strategy for sludge treatment and phosphate recovery in wastewater treatment plants (WWTPs) and potential agronomic application.

GDMR-Net: A Novel Graphic Detection Neural Network via Multi-Crossed Attention and Rotation Annotation for Agronomic Applications in Supply Cyber Security

GDMR-Net: A Novel Graphic Detection Neural Network via Multi-Crossed Attention and Rotation Annotation for Agronomic Applications in Supply Cyber Security

The role of microbial interactions on rhizobial fitness.

Rhizobia are soil bacteria that can establish a nitrogen-fixing symbiosis with legume plants. As horizontally transmitted symbionts, the life cycle of rhizobia includes a free-living phase in the soil and a plant-associated symbiotic phase. Throughout this life cycle, rhizobia are exposed to a myriad of other microorganisms that interact with them, modulating their fitness and symbiotic performance. In this review, we describe the diversity of interactions between rhizobia and other microorganisms that can occur in the rhizosphere, during the initiation of nodulation, and within nodules. Some of these rhizobia-microbe interactions are indirect, and occur when the presence of some microbes modifies plant physiology in a way that feeds back on rhizobial fitness. We further describe how these interactions can impose significant selective pressures on rhizobia and modify their evolutionary trajectories. More extensive investigations on the eco-evolutionary dynamics of rhizobia in complex biotic environments will likely reveal fascinating new aspects of this well-studied symbiotic interaction and provide critical knowledge for future agronomical applications.

Symbiosis between cyanobacteria and plants: from molecular studies to agronomic applications.

Nitrogen-fixing cyanobacteria from the order Nostocales are able to establish symbiotic relationships with diverse plant species. They are promiscuous symbionts, as the same strain of cyanobacterium is able to form symbiotic biological nitrogen-fixing relationships with different plants species. This review will focus on the different types of cyanobacterial-plant associations, both endophytic and epiphytic, and provide insights from a structural viewpoint, as well as our current understanding of the mechanisms involved in the symbiotic crosstalk. In all these symbioses, the benefit for the plant is clear; it obtains from the cyanobacterium fixed nitrogen and other bioactive compounds, such as phytohormones, polysaccharides, siderophores, or vitamins, leading to enhanced plant growth and productivity. Additionally, there is increasing use of different cyanobacterial species as bio-inoculants for biological nitrogen fixation to improve soil fertility and crop production, thus providing an eco-friendly, alternative, and sustainable approach to reduce the over-reliance on synthetic chemical fertilizers.

Induction of antioxidant defenses by a low-dose cadmium priming alleviates heat stress in pigeon pea

Global warming has a devastating effect on the growth and productivity of plants. Pigeon pea, the second most important legume crop with high nutritional value, is at high risk due to high temperature exposure. Priming is an innovative agronomical application that can be used as a strategy to minimize the detrimental effects of any kind of stresses. In this study, we investigated how low dose of cadmium priming alleviates heat stress (HS) in pigeon pea seedlings. The results demonstrated that low dose of cadmium priming induced the expression of antioxidant systems and maintain a redox homeostasis. An enhanced level of antioxidant glutathione, and antioxidative enzymes (SOD, APX, and GR) were observed in Cd+HS leaf (40 μM Cd priming followed by exposure to HS, 42°C) as compared to the HS leaf. Moreover, a reduction in hydrogen peroxide (H2O2) and oxidized glutathione (GSSG) content was also noticed in Cd+HS leaf. The GSH/GSSG ratio, which was indicative of the redox state in the plant system, was also high in Cd+HS leaf as compared to HS leaf. Thus, the priming of pigeon pea seeds with low dose Cd alleviates HS by elevating antioxidant defenses, ultimately protecting pigeon pea seedlings against HS.

Eco‐friendly three‐dimensional hydrogels for sustainable agricultural applications: Current and future scenarios

AbstractModern world is searching for water efficient agriculture techniques as irrigation is becoming scarce. Limited water resources and more food demand are the two key challenges in agriculture. Hydrogels which can respond intelligently by pH, temperature, light, ionic strength, osmotic pressure, magnetic or electric field changes are termed as intelligent or smart hydrogels which are analogous to conventional hydrogels in preparatory methods and features. Lag phase, constant release and decay phase are three steps involved in release of nutrients from polymeric hydrogels. In fact, hydrogels act as little reservoirs of water and dissolve nutrients that are released in controlled manner anchored by plant roots via capillary action. Hydrogels also sustain optimum amount of water in water stress conditions and reabsorb water in moist conditions which ultimately increases seedling, seed germination, plant growth and crop yield. Fertilizer and salt release are majorly dependent upon pH and temperature followed by diffusion‐controlled mechanism. Cross‐linkers, binders and fillers play pivotal role in determining properties, architecture and hydrogel pores. In comparison to potassium (K+) and phosphate (PO4−3) ions, nitrates (NO3−1) and ammonium (NH4+1) ions exhibited faster release rate. This review spotlights application prospects of three dimensional hydrogel in agriculture. Initially, properties of hydrogels, their classification, preparatory methods, effect of natural‐synthetic‐polymer blending and role of fillers are stated. Afterward, hydrogel functioning, significance, advantages, mechanism of fertilizer release and agriculture specific applications of hydrogels are comprehensively described. In conclusion, extraordinary biocompatible, cheaper, stable, biodegradable, durable, non‐toxic and re‐wettable characteristics of hydrogel systems motivated their utilization in agronomical applications.

Rock phosphate improves nutrient uptake and oil accumulation in olive fruit

Phosphorus deficiency is one of the main constraints to olive production in alkaline soils. The high cost of phosphorus fertilizers may represent an insurmountable obstacle in many countries, leaving the exploitation of their own rock phosphate (RP) as the only low-cost and long-term alternative. The aim of this work was to study the long-term effect of agronomic application of RP (amounts applied: 150 kg ha−1) in a field of olive trees on specific microbial groups in the rhizosphere, nutrient uptake and oil accumulation in the fruit. The results revealed that agronomic application of RP increased the rhizosphere fatty acid methyl ester (FAME) biomarkers indicative of Gram-negative bacteria, fungi and actinobacteria. The level of FAME 16:1ω5 in rhizosphere decreased significantly after agronomic application of RP, indicating that the functioning of arbuscular mycorrhizas was altered. Decreased FAME 16:1ω5 due to RP amendment was not associated with a significant reduction of nutrient concentrations in the olive root; while a significant increase in root P and K contents was observed. However, the level of N did not appear to be significantly influenced. The experimental results also showed that RP-fertilized plants had significantly greater fruit weight and pulp/stone ratio. Fruits of RP-fertilized plants also had significantly higher oil content (+8.67% on average). Our results support the hypothesis that, following agronomic application of RP, the complex interactions of root and microbial community in the olive rhizosphere is a potential factor influencing oil accumulation in the olive fruit.