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Optimizing mung bean productivity and root morphology with biofertilizers for sustainable farming
Full text linkThe excessive use of chemical fertilizers has raised major environmental and economic concerns in legume cultivation. This study assessed the effects of various fertilizers, including biofertilizers and chemical nitrogen, on yield, root characteristics, and nutrient dynamics in two mung bean genotypes (Partow, IC418452). Field trials were conducted over a two-year period in Mashhad, Iran, using a factorial randomized block design. Treatments included two genotypes and six fertilizer levels: control, N-fixing bacteria (FLNF), P-solubilizing bacteria (PSB), K-solubilizing bacteria (KSB), a consortium (FLNF + PSB + KSB), and Urea. Yield components, biomass, root morphology, nodulation, and plant/soil NPK concentrations were measured and analyzed. Fertilizers significantly affected yield, biomass, root structure, and nutrient uptake. Urea yielded the highest biomass, grain yield, and root area, especially in Partow. However, the microbial consortium significantly improved yield components compared to the control and uniquely maximized root nodulation and inoculation percentage, indicating an enhanced biological nitrogen fixation potential. On average across the two seasons, urea increased grain yield by 46% and biomass by 41% relative to the control, whereas the microbial consortium enhanced root nodulation by 62% and yield by 32%. Significant genotype×fertilizer interactions highlighted genotype-specific responses. Nodulation correlated positively with yield. Both urea and the PGPR consortium significantly increased mung bean productivity. While urea maximized yield, the consortium provided considerable yield gains and enhanced biological nitrogen fixation potential, presenting a viable and sustainable alternative to reduce reliance on chemical nitrogen. The goal was to understand the relationships between root morphology, nutrient utilization, and yield to promote sustainable, high-yield mung bean cultivation. These findings highlight the potential of multi-strain biofertilizers to maintain mung-bean productivity while reducing dependence on synthetic N inputs.Open Access funding enabled and organized by Projekt DEAL.Universität Hohenheim (3153
Effects of dietary phosphorus and myo-inositol supplementation on NaPi-IIb and TRPV6 protein expression in duodenal apical membranes of laying hens from two strains
Full text linkPhosphorus (P) and calcium (Ca) absorption in the intestine is mediated by apical brush border membrane (BBM) transporters, including the sodium-dependent phosphate (Pi) transporter NaPi-IIb and the Ca²⁺-selective channel TRPV6. Both are highly expressed in the duodenum and exhibit dietary adaptability; yet little is known about how this adaptability varies with strain and age in laying hens. The present study examined the effects of dietary mineral P renunciation and myo-inositol (MI) supplementation on NaPi-IIb and TRPV6 protein expression in the duodenal BBM of Lohmann Brown-Classic (LB) and Lohmann LSL-Classic (LSL) hens. Two independent feeding trials were conducted: hens received diets either with or without mineral P supplementation (wk 15 - 19 and 20 – 24), or with graded MI levels (0 - 3 g/kg; wk 26 – 30). At the end of each period, hens were euthanized and protein expression of NaPi-IIb and TRPV6 in duodenal BBM was studied by western blotting. Statistical correlation with additional traits of mineral metabolism was analyzed. An immunoreactive NaPi-IIb band was detected at ∼ 45 kDa; therefore, all results reported here refer to this NaPi-IIb fragment. Mineral P renunciation did not affect NaPi-IIb fragment or TRPV6 expression in either hen strain. In LSL hens NaPi-IIb fragment expression increased from wk 19 to wk 24, whereas in LB hens it remained unchanged. NaPi-IIb fragment expression was positively associated with duodenal phosphatase activity and plasma estradiol. TRPV6 expression tended to reduce in LB hens from wk 19 to wk 24, but remained stable in LSL hens. TRPV6 expression was positively associated with duodeno-jejunal P content. MI supplementation upregulated NaPi-IIb fragment expression in LB, but downregulated it in LSL hens with high dietary MI levels, without affecting TRPV6. These findings demonstrate strain-dependent regulatory patterns of duodenal expression of NaPi-IIb fragment and TRPV6 in response to physiological stage and MI supply, indicating that mineral feeding strategies may benefit from genotype-specific consideration, whereas the mechanisms underlying MI-related effects require further clarification
Editorial: Precision information identification and integrated control: pest identification, crop health monitoring, and field management
Full text linkToward food-grade production of the Bacteroides helcogenes protein-glutamine glutaminase with an optimized Bacillus subtilis strain
Full text linkProtein-glutamine glutaminases (PGs; EC 3.5.1.44) have gained attention in the food industry due to their application in plant protein products. The recently discovered PG from Bacteroides helcogenes (PGB) has especially been shown to provide promising characteristics for improving the techno-functional properties of plant proteins. A prerequisite for food enzymes, such as the PG, is their production with an expression host that meets food safety and yield requirements. The antibiotic-free and secretory production of the PGB was targeted in this study using the undomesticated Bacillus subtilis 007. The CRISPR/Cas9-mediated approach enabled specific genomic PGB integrations, while simultaneously deleting unwanted B. subtilis traits. Firstly, the PGB expression cassette was integrated into the sigF gene, leading to an asporogenic strain and extracellular activity of 4.1 µkat/Lculture in bioreactor cultivations. However, excessive foaming hampered the production process tremendously. Consequently, a second PGB copy was integrated into the sfp locus, which is involved in the production of lipopeptides, such as surfactin. As a result, the PGB activity was increased to 5.4 µkat/Lculture, and foaming during cultivation was reduced significantly. The introduction of a third PGB copy for preventing cell motility did not increase production; however, the integration into the well-established amyE locus improved the PGB yield during reactor cultivations. A final extracellular activity of 9.5 µkat/Lculture was reached. The multiple genomic integrations of the PGB gene enabled the efficient PGB secretion in an optimized B. subtilis host without the need for antibiotics.Key points• Site-specific PGB integration enabled by genome sequencing of B. subtilis 007.• Antibiotic-free and secretory PGB production with an optimized B. subtilis host.• Increased PGB production reaching 9.5 µkat/Lculture.Open Access funding enabled and organized by Projekt DEAL.Universität Hohenheim (3153
Regression approaches for modeling genotype-environment interaction and making predictions into unseen environments
Full text linkIn plant breeding and variety testing, there is an increasing interest in making use of environmental information to enhance predictions for new environments. Here, we will review linear mixed models that have been proposed for this purpose. The emphasis will be on predictions and on methods to assess the uncertainty of predictions for new environments. Our point of departure is straight-line regression, which may be extended to multiple environmental covariates and genotype-specific responses. When observable environmental covariates are used, this is also known as factorial regression. Early work along these lines can be traced back to Stringfield & Salter (1934) and Yates & Cochran (1938), who proposed a method nowadays best known as Finlay-Wilkinson regression. This method, in turn, has close ties with regression on latent environmental covariates and factor-analytic variance-covariance structures for genotype-environment interaction. Extensions of these approaches – reduced rank regression, kernel- or kinship-based approaches, random coefficient regression, and extended Finlay-Wilkinson regression – will be the focus of this paper. Our objective is to demonstrate how seemingly disparate methods are very closely linked and fall within a common model-based prediction framework. The framework considers environments as random throughout, with genotypes also modeled as random in most cases. We will discuss options for assessing uncertainty of predictions, including cross validation and model-based estimates of uncertainty, the latter one being estimated using our new suggested approach. The methods are illustrated using a long-term rice variety trial dataset from Bangladesh.Open Access funding enabled and organized by Projekt DEAL.Deutsche Forschungsgemeinschafthttp://dx.doi.org/10.13039/501100001659Universität Hohenheim (3153
Miscanthus‐derived products for material applications: can they contribute to greenhouse gas emission mitigation?
No full textMiscanthus is a particularly promising lignocellulosic biomass as it can also grow under marginal conditions and can be used for a wide range of products including energy and material applications. The latter, including applications in the construction, textile, chemical, or agricultural sector, is becoming increasingly relevant today. In general, it is hypothesised that biobased products are advantageous in terms of their greenhouse gas (GHG) performance when compared to conventional—in particular fossil—alternatives. To investigate this, the life cycle assessment methodology is typically applied. However, assessments are subject to uncertainty and variability due to assumptions and methodological choices. Given the increasing interest in miscanthus‐derived material applications, this study aims to draw more general conclusions about their GHG performance and relative mitigation potential. This should support a better understanding of their contribution to climate change mitigation objectives and guide the selection of promising products or product groups. A systematic review of peer‐reviewed literature was conducted. In total, 20 studies reporting on 188 comparisons of the GHG performance of miscanthus‐derived and alternative products were assessed. Most comparisons indicated potential GHG mitigation through miscanthus‐derived products, with the majority ranging between 20% and 100% savings. Key parameters defining the relative performance include the selection of the reference product, consideration of soil carbon changes, changes in product and process design, as well as the incorporation of indirect Land Use Change (iLUC) impacts. Overall, we conclude that miscanthus‐derived material applications have the potential to contribute to GHG emission mitigation if iLUC effects are minimised. Given the limited availability of agricultural land, miscanthus‐derived products with high absolute GHG mitigation potential per unit of biomass used and long product lifetime are preferable. For future development, potential environmental trade‐offs need to be monitored.Universität Hohenheim 10.13039/100009613Horizon 2020 Framework Programme 10.13039/10001066
Digital innovations and institutional barriers in agricultural input subsidy programmes in sub‐Saharan Africa: evidence from Nigeria
Full text linkMotivation: Agricultural input subsidy programmes are crucial for improving agricultural productivity in sub‐Saharan Africa (SSA). However, there is little empirical evidence on how second‐generation input subsidy programmes (SISPs) based on information and communication technology (ICT) are implemented and the institutional challenges that undermine their effectiveness. Purpose: This article assesses the implementation of ICT‐based SISPs and their challenges in SSA using the Nigerian e‐wallet input subsidy programme as a case study. We draw on a conceptual framework that integrates the national innovation system (NIS), contingency theory, and new institutional economics. Approach and methods: We analysed expert interviews and participatory qualitative data from Process Net‐Maps and focus group discussions (FGDs) using content and Process Net‐Map analyses. Findings: The results show that over 20 public, private and community actors were involved in implementing the e‐wallet SISP across five stages. The programme increased private‐sector participation, reduced corruption, improved recipient targeting, and speeded up input delivery compared to first‐generation input programmes. However, weak institutional arrangements (such as poor funding, restricted institutional collaborations, and stakeholder capability gaps) undermined the innovation aspect of the e‐wallet SISP. The programme also faced five main challenges: policy inconsistency, poor information flow and weak reporting, moral hazards such as “round‐tripping,” input leakage and diversion, and elite capture. The study concludes that institutional constraints, rigid organizational structures, and a narrow focus on solving first‐generation programme challenges limited the ability of actors to adapt to new and evolving challenges. Policy implications: Effective SISPs and input policies require supportive institutional environments that allow actors from all sectors to function effectively. Programmes should thus be designed and managed with flexible and organic structures that foster collaboration among private, public, and community stakeholders. Continuous, stage‐specific evaluations and smart governance tools, such as real‐time mobile data collection and buy‐back initiatives, can strengthen monitoring, input tracking, accountability, and input use incentives.Bundesministerium für Bildung und Forschung 10.13039/50110000234
Model-based process design for surfactin production with Bacillus subtilis
Full text linkBacillus subtilis is one of the most important production organisms in industrial biotechnology. However, there is still limited knowledge about the kinetics of fed-batch processes in bioreactors, as well as a lack of biological performance indicators, such as production yields, particularly regarding their variation over time. Understanding these kinetics and changes is crucial for optimizing the productivity in fed-batch processes. Fed-batch bioreactor cultures of Bacillus subtilis BMV9 in high cell density processes for surfactin production have been characterized with a kinetic model composed of first-order ordinary differential equations, describing the time course of biomass, substrate, surfactin and acetate. This model contributes to understanding critical restrictions and the knowledge gained was used to design and implement a model-based process. The model integrates biomass growth based on Monod kinetics, substrate consumption, surfactin synthesis and formation of the by-product acetate. After the model was parameterized for B. subtilis BMV9 using 12 different fed-batch bioreactor experiments, the kinetic model was able to accurately describe biomass accumulation, substrate consumption, product formation rates and, to some extent, the overflow metabolism involving acetate. Based on this, the kinetic model was used for a process design, in which the batch was omitted, which led to a product titre of 46.33 g/L and a space–time-yield of 2.11 g/(L*h) was achieved. The kinetic model developed in this study enables the description of the time course of biomass growth, substrate consumption and product formation and thus significantly improves process understanding. The computation of process parameters, which are not analytically accessible at any time, could be realized. A sensitivity analysis identified the maximum specific growth rate, substrate-related maintenance and the maximum acetate formation rate as key parameters influencing model outputs.Open Access funding enabled and organized by Projekt DEAL.Universität Hohenheim (3153
Leveraging regionally sourced natural fibers for coreless filament winding in sustainable construction
Full text linkThis study investigates the potential of regionally sourced natural fibers (NF) as sustainable feedstocks for coreless filament winding (CFW), an innovative and resource-efficient composite fabrication method for construction. As the sector moves towards bio-based materials, flax has emerged as a benchmark due to its compatibility with CFW and favorable mechanical properties. However, supply chain vulnerabilities and price volatility highlight the need for regional alternatives to flax fibers. By assessing hemp, miscanthus, lavender, nettle and wheat straw cultivated in Baden-Württemberg (BW), this paper links crop sustainability and fiber suitability with the broader aim of strengthening local biomass utilization within the bioeconomy. A multi-stage evaluation framework compares environmental, economic, social, and technical indicators against flax, focusing on biomass availability, input intensity, ecosystem services, land-use competition, and fiber properties. The results identify hemp as the most promising alternative due to its high fiber output, low cultivation inputs, beneficial ecosystem services and mechanical performance. Nettle offers strong mechanical performance but faces agronomic limitations, while lavender presents niche potential under integrated production systems. Miscanthus and wheat straw, while unsuitable for direct CFW due to fiber morphology, may serve as supplementary feedstocks through modified processing. These findings underscore the role of local biomass streams in creating robust regional value chains, contributing to the resilience and sustainability of the bioeconomy. While the focus of this study is on BW, the framework can be transferred to other regions and may serve as a practical tool for policy, industry, and research seeking to advance circular approaches in bio-based construction
Effect of phosphorus fertilizer placement depth, amount, and soil water content on early maize growth
Full text linkBackground: Drought stress (DS) reduces soil phosphorus (P) availability by limiting P diffusion and uptake, while global P resource scarcity exacerbates nutrient limitations for crops.
Aim: This study investigated whether deep subsurface P placement could alleviate the combined effects of P deficiency and DS on maize growth.
Methods: A greenhouse trial with maize (cv. Ricardinio) was conducted involving three factors: three P fertilizer amounts (0 mg P pot −1 [NP], 109 mg P pot −1 [LP], and 655 mg P pot −1 [HP]), three placement depths (0–9 cm [U, upper layer], 9–18 cm [L, lower layer], and uniformly mixed throughout 0–18 cm [M]), and two soil water contents (45% of soil water holding capacity [WHC] [DS] and 75% WHC [WW]). Root and shoot traits were assessed at the fourth‐ and tenth‐leaf stages.
Results: LP significantly reduced shoot biomass and P content compared to HP treatment. At the fourth‐leaf stage, DS increased root biomass by 69.3% and 27.1% in the 9–18 cm and 0–18 cm layers compared to WW treatment. At the tenth‐leaf stage, DS reduced root biomass by at least 41% across layers and decreased shoot growth and P uptake. Under DS, L‐DS increased root growth and root length in the 9–18 cm layer compared to M‐DS and U‐DS treatments but did not improve shoot traits.
Conclusion: Deep subsurface P placement promoted deeper root development under drought and P deficiency. However, its benefits on shoot growth were not evident in early stages, indicating the need for longer term field validation.Deutsche Forschungsgemeinschaft 10.13039/501100001659China Scholarship Council 10.13039/50110000454