Superabsorbent biopolymers for climate-smart fertilizer technology: advancing nitrogen–water interactions for sustainable agriculture

Towards environmental Sustainability: Devolving the influence of carbon dioxide emission to population growth, climate change, Forestry, livestock and crops production in Pakistan

Human population is increasing from 7.6 billion today to an estimated 9.5–10 billion by 2050.1 How can billions more people, with increasing demands for protein and other food sources, be adequately fed without destroying the environment? Utilizing more land for agricultural purposes is not a solution, given that much of the arable land on the planet is already being used for food, fiber, chemical, or fuel production.2 One answer to this complex challenge will lie in the ability to produce more food within the current footprint in sustainable and affordable ways. By one definition, “an agricultural biologicals system is an ecologically, socially, and economically sustainable agricultural production system that promotes safe products by minimizing environmental adverse consequences and reducing the use of non-renewable natural resources.”3 In this article, we discuss opportunities that capitalize on twenty-first century technological innovation and the central role played by the microbial life intimately associated with plants: the plant and soil microbiomes. We examine the potential of Ag biologicals within the agricultural ecosystem. We elucidate their functionality as a means of increasing plant health and crop yields while maintaining environmental sustainability. Finally we illustrate the role that NewLeaf Symbiotics (St. Louis, MO) plays in the introduction of a range of Ag biologicals based on methylobacteria, or M-trophs—bio-complementary products that infuse plants with microbes that are tailored to fit specific crop genetics and environmental conditions.4 Most major agricultural input suppliers and seed companies recognize that biologicals represent a largely untapped opportunity to meet demand for novel and sustainable complements to the existing roster of agricultural chemicals, fertilizers, and genetically modified (GM) traits. Recent government, industrial, and private investments support the belief that significant improvements in crop productivity and environmental sustainability are achievable using complementary biological inputs. Between 2012 and 2015, over $2 billion was invested by Ag multinationals in agreements, mergers, and the acquisition of small biologicals companies.5 These investments are driving the development of the next generation of Ag biologicals. The broad recognition of the agricultural significance of the plant and soil microbiome is supported in large part by the reduced cost, increased speed, and improved accuracy of genomic sequencing. Simultaneous increases in computing power and analytics are driving the rapid evolution of new molecular biology tools directed at solving previously intractable problems. The recognition of the phyto-microbiome as a second genome, with the potential to supplement and interact with the plant genome, offers significant opportunity to improve crop health and yield.6 The persistent evolution of pest resistance to chemical pesticides and traits, combined with consumer demand for sustainable farming and food traceability, have created a strong and growing interest in new Ag biologicals.7 In the US there are 350-plus registered biocontrol agents based on 50-plus species. The market is growing at an average compounded annual growth rate (CAGR) greater than 14%. Every major international and domestic supplier of agronomic inputs is investing in this area. Since most Ag biological products are based on naturally occurring microbes, consumer health and safety concerns about these products are reasonably mitigated. Growers are aware and ready to try new biologicals, in part because biological products like rhizobia and Bacillus thuringiensis (Bt) have been used and accepted for decades. There are, however, significant obstacles to the introduction of novel and efficacious Ag biologicals. Microbes are part of extremely complex soil and plant systems; discovery and delivery of effective products are no simple tasks. Historically, some Ag biological market offerings failed to deliver consistent efficacy equal to conventional inputs, causing the industry to regard Ag biologicals with some caution. Improved strains, advanced formulations, and recognition of the unique value Ag biologicals can provide has led to an increase in their global market share over the past decade from less than 1% to more than 5%. Two of the major strategic challenges to increased use of Ag biologicals are: ▪ Optimization of discovery, screening, and derivation of candidate microbes, and ▪ Alignment of product development with technical and economic drivers of contemporary production farming.

In order to develop sustainable production of greenhouse crops, the economic, energy, and environmental aspects of production should be considered. The purpose of this study was to evaluate the economic, energy, and environmental (3E) sustainability of cucumber, tomato, and bell pepper production in greenhouses by performing material flow cost accounting (MFCA) and life cycle assessment (LCA) material and methods. Calculating the economic and energy value of losses in agricultural sustainability assessment studies is not common. Using the LCA method alone does not allow us to calculate the monetary and energy value of waste. If this method is used simultaneously with MFCA, this gap will be filled. The system boundary for LCA was from cradle to farm, and for MFCA, foreground processes were considered. The production of each crop was compared at the level of 1000 m2 during 1year. Data were collected through questionnaire-based interviews. The gross value of production for cucumber, tomato, and bell pepper were 8982, 16387, and 17610 $/1000 m2, respectively. The negative production of cucumber, tomato, and bell pepper were 702, 718, and 449 $/1000 m2, respectively. The benefit-to-cost ratio in the production of cucumber, tomato, and bell pepper was calculated as 2.8, 5.17, and 5.8, respectively. The economic productivity in the production of cucumber, tomato, and bell pepper was calculated at 10.25, 7, and 4.4kg/$. Labor cost was the main cost in the production of all three crops. The total input energy for the production of cucumber, tomato, and bell pepper was estimated to be 99.4, 123.1, and 164.6 GJ/1000 m2, respectively. Negative products in the production of cucumber, tomato, and bell pepper were obtained at - 24.2, - 23.9, and - 13.5 GJ/1000 m2, respectively. The energy productivity of cucumber, tomato, and bell pepper was calculated as 0.23, 0.26, and 0.08kg/MJ, respectively. The specific energy indices were 4.32, 3.79, and 12.20MJ/kg for cucumber, tomato, and bell pepper, respectively. The energy ratio in the production of tomato (0.02) was higher than bell pepper (- 0.02) and cucumber (- 0.06). From the perspective of energy, electricity was recognized as the hotspot for the production of three crops. Global warming (GWP100a), ozone layer depletion (ODP), acidification (AC), and eutrophication (EP) indices were calculated for all three crops. Tomato production was ranked first in all impact categories. On-farm emissions and electricity consumption were identified as environmental hotspots. The subsidized price of electricity, natural gas, and chemical fertilizers has led to their excessive use in the production of greenhouse plants. It can be concluded that bell pepper has the best performance from an economic point of view. However, its production is not justified in terms of energy. Tomato was ranked first in terms of energy, and cucumber was ranked first in terms of low environmental impacts. The production of these plants with energy and chemical fertilizer subsidies is currently cost-effective. If the prices are corrected, the production of these plants will face serious challenges. Producing electricity from sunlight and mechanizing production processes can be a solution to these challenges.

Plant growth stimulators (growth regulators + biostimulants; PGS) are chemical substances (organic/inorganic), helpful in plant growth and development. These are not considered as the replacement of fertilizers but can help in improved crop and soil quality. Both compounds can amplify the root biomass, nutrients translocation, enzymatic activities, crop yield, physiology, and nutrient uptake. Biostimulants are rich in minerals, vitamins, plant hormones, oligosaccharides, and amino acids. These compounds have a serious role to improve soil health, fertility, sorption, and desorption of nutrients. Hence, have a vital character in nutrients cycling, abiotic stress control, heavy metals bioavailability, and greenhouse gaseous emission. This chapter focuses on the discussions about the influence of plant growth regulators and biostimulants in crop production, soil health, heavy metal cycling, greenhouse gases emission with environmental sustainability. Whereas, the impact of biostimulants on greenhouse gases is a research gap.

Exploring wheat-based management strategies to balance agricultural production and environmental sustainability in a wheat−maize cropping system using the DNDC model

Nitrogen is one of the most essential nutrients for plants. It is regarded as the single most important factor limiting growth of crops. The major inorganic forms of N that predominate in croplands are NO3- and NH4 + The availability of N in the soil is limited due to adverse environmental conditions such as salinity, water deficit, low light intensity, heat, chilling, excess levels of metals in the soil, and UV-B radiation. These stresses reduce N uptake, cause adverse effects on N assimilation in the tissues, and drastically affect crop yields. Plants possess multiple NO3- uptake and transport systems to optimize N use with changing soil and environmental conditions. Depending on the soil NO3- concentration, two NO3- uptake systems high-affinity transport system (HATS) and low-affinity transport system (LATS) operate in plants. Five gene families of nitrate transporters (NRTs) have been characterized that are involved in uptake, transport, and storage of NO3- within the tissues. From the soil, NO3- is taken up by plant roots via NRTs; thereafter, NO3 – gets assimilated into organic compounds by the action of NO3- assimilatory enzymes. The processes of NO3- uptake, its translocation within the tissues, and its reduction are coordinately regulated. Most of the stressful conditions cause a decrease in NO3- uptake and inhibition in the activities of N assimilatory enzymes nitrate reductase (NR) and glutamine synthetase (GS). The NR is inducible by NO3- and its activity is subject to regulation by a variety of environmental conditions that are influenced under stresses. Environmental stresses adversely affect the behavior of enzymes of NO3- and NH4 + assimilation. Genotypes of plants differing in stress tolerance show varying activity behaviors of NR and other N assimilatory enzymes. Though extensive studies have been performed to unveil the biochemical mechanisms underlying the uptake of NO3- by plants, the process of its assimilation, and the regulation of enzymes of NO3- assimilation, our knowledge is still insufficient to address the complexities associated with effects of the varieties of abiotic stresses on N uptake and assimilation processes. The precise biochemical mechanisms on how adverse conditions of the environment reduce NO3- uptake and inhibit NR activity need to be investigated in more detail. Little information is available regarding molecular events of NO3- uptake, the NO3 – sensor protein system, signal transduction of environmental NO3-, NO3- induction regulatory proteins, primary responsive genes that are transcribed and translated as a result of NO3- induction, etc. Besides this, the nature of different families of NRTs, NO3- translocators, events involving overall induction of NR by NO3-, and regulation of NR and other N assimilatory enzymes under various environmental stresses like salinity, drought, heat, chilling, light, and excessive levels of metals in the soil need to be examined in greater detail. In certain cases, such as salinity and water stresses, suppression of the GS/GOGAT pathway and a sustained level of induction of the glutamate dehydrogenase (GDH) pathway of ammonium assimilation are observed. Thus, the role of aminating GDH as antistress enzyme needs to be examined under a wide range of stresses. A detailed understanding of the physiological and molecular controls of N uptake and assimilation in crop plants under different stressful conditions will help in identifying suitable genotypes with better N use efficiency for cultivation in stress-prone areas.

Sustainable biochar effects for low carbon crop production: A 5-crop season field experiment on a low fertility soil from Central China

Drought stress is a major abiotic stress threatening plant and crop productivity. In case of fleshy fruits, understanding mechanisms governing water and carbon accumulations and identifying genes, QTLs and phenotypes, that will enable trade-offs between fruit growth and quality under Water Deficit (WD) condition is a crucial challenge for breeders and growers. In the present work, 117 recombinant inbred lines of a population of Solanum lycopersicum were phenotyped under control and WD conditions. Plant water status, fruit growth and composition were measured and data were used to calibrate a process-based model describing water and carbon fluxes in a growing fruit as a function of plant and environment. Eight genotype-dependent model parameters were estimated using a multiobjective evolutionary algorithm in order to minimize the prediction errors of fruit dry and fresh mass throughout fruit development. WD increased the fruit dry matter content (up to 85%) and decreased its fresh weight (up to 60%), big fruit size genotypes being the most sensitive. The mean normalized root mean squared errors of the predictions ranged between 16–18% in the population. Variability in model genotypic parameters allowed us to explore diverse genetic strategies in response to WD. An interesting group of genotypes could be discriminated in which (i) the low loss of fresh mass under WD was associated with high active uptake of sugars and low value of the maximum cell wall extensibility, and (ii) the high dry matter content in control treatment (C) was associated with a slow decrease of mass flow. Using 501 SNP markers genotyped across the genome, a QTL analysis of model parameters allowed to detect three main QTLs related to xylem and phloem conductivities, on chromosomes 2, 4, and 8. The model was then applied to design ideotypes with high dry matter content in C condition and low fresh mass loss in WD condition. The ideotypes outperformed the RILs especially for large and medium fruit-size genotypes, by combining high pedicel conductance and high active uptake of sugars. Interestingly, five small fruit-size RILs were close to the selected ideotypes, and likely bear interesting traits and alleles for adaptation to WD.

Climate change poses significant challenges to global food security by disrupting agricultural nutrient dynamics through increased temperatures, altered precipitation patterns, and extreme weather events. These changes threaten crop productivity, soil health, and environmental sustainability. Traditional nutrient management practices, often reliant on excessive chemical fertilizer use, contribute to nutrient losses, soil degradation, and greenhouse gas emissions. This review systematically analyzes 65 peer-reviewed studies (1998–2024) selected using PRISMA guidelines, supplemented by bibliometric tools, to evaluate nutrient management strategies under climate change. The results highlight climate change's multifaceted impacts on soil nutrient cycles, microbial activity, crop physiology, and crop yield. Elevated temperatures and CO2 levels alter nutrient availability and reduce grain quality, while erratic rainfall patterns exacerbate nutrient losses through leaching and runoff. Conventional fertilizer practices are shown to be inefficient and environmentally harmful, prompting a shift toward integrated nutrient management, precision agriculture, and biofertilizers. Emerging strategies such as slow- and controlled-release fertilizers, site-specific nutrient management, and decision support systems significantly improve nutrient use efficiency and reduce greenhouse gas emissions. Conservation agriculture and organic amendments further enhance soil health and resilience. The discussion highlights that integrated and adaptive nutrient management frameworks, supported by technology and agroecological practices, are critical for maintaining high productivity while minimizing environmental impacts under climate change. These approaches collectively support sustainable crop production, mitigate climate impacts, and promote long-term soil fertility. The review concludes that nutrient management is central to climate-smart agriculture and offers actionable insights for researchers, farmers, and policymakers aiming to secure food systems in a changing climate.

AquaCrop modeling to explore optimal irrigation of winter wheat for improving grain yield and water productivity

Due to continuous growth of world population, there is dire need of serious efforts and innovative approaches to meet food demands through sustainable production practices, improvement in supply chain, and control of food wastage. All these efforts should ensure the access to nutritious food to all suffering from hunger and malnutrition. Due to intensive crop cultivation and use of synthetic fertilizers, soil health is seriously deteriorating. However, soil fertility can be improved by incorporating legumes in the cropping system and/or use of rhizobial inoculants, which not only increase nitrogen fixation but also improve soil fertility and crop production through several other attributes such as phosphate solubilization, siderophores production, phytohormones production, enzymes synthesis, and exopolysaccharides production. Moreover, these bacteria can be helpful for improvement in crop production on marginal lands due to their tolerance against various biotic and abiotic stresses. All these characteristics make rhizobia equally important for non-legumes as for legumes. The use of rhizobial inoculants can ensure improvement in crop productivity and environment sustainability by enhancing soil fertility and reduction in use of synthetic chemical fertilizers. Present review focuses on important plant growth-promoting mechanisms of rhizobia and the use of these rhizobia for sustainable crop production through improvement in crop nutrition, physiology, productivity, and stress tolerance of crop plants. The potential of the synergistic use of rhizobia with other soil microorganisms for sustainable agriculture has also been elucidated with examples, followed by their future prospects.

Do soil conservation practices exceed their relevance as a countermeasure to greenhouse gases emissions and increase crop productivity in agriculture?

Rice crop production plays a vital role in food security of India, contributing more than 40% to overall crop production. High crop production is dependent on suitable climatic conditions. Detrimental seasonal climate conditions such as low rainfall or temperature extremes can dramatically reduce crop yield. Developing better techniques to predict crop productivity in different climatic conditions can assist farmer and other stakeholders in important decision making in terms of agronomy and crop choice. This paper reports on the use of Bayesian Networks to predict rice crop yield for Maharashtra state, India. For this study, 27 districts of Maharashtra were selected on the basis of available data from publicly available Indian Government records with various climate and crop parameters selected. The parameters selected for the study were precipitation, minimum temperature, average temperature, maximum temperature, reference crop evapotranspiration, area, production and yield for the Kharif season (June to November) for the years 1998 to 2002. The dataset was processed using the WEKA tool. The classifiers used in the study were BayesNet and NaiveBayes. The experimental results showed that the performance of BayesNet was much better compared with NaiveBayes for the dataset.

Trade-offs between crop production and GHG emissions following organic material inputs in wheat-maize systems.

Mitigating life-cycle multiple environmental burdens while increasing ecosystem economic benefit and crop productivity with regional universal nitrogen strategy