Research into the symbiotic relationship between plants and arbuscular mycorrhizal fungi (AMF) is key for sustainable agricultural intensification. The objective of the present study is to evaluate native AMF at the monosporic level in greenhouse-grown, economically important crops. Agricultural soil samples from three locations (Saltillo, Zaragoza, and Parras) were obtained by combining portions resulting from a zigzag sampling pattern. From these samples, 15 morphotypes were extracted according to a modified Gerdemann’s technique and monosporically inoculated on melon, cucumber, tomato, and onion, 30 days after their sowing. Under a completely random experimental design, 16 treatments with three repetitions were defined. Plant height, root length, stem diameter, total fresh weight, fresh root weight, dry root weight, bulb weight, fresh leaf weight, total dry weight, flower number, leaf number, fruit number, spore number, and percentage of colonization were all evaluated. The results were subjected to the analysis of variance (ANOVA) and the Tukey comparison test (p ≤ 0.05), which showed that the monosporic inoculation favors significantly the AMF and the host, while the T6 (Saltillo spore + Steiner modified with 20% of the normal phosphorus concentration) showed a greater response uniformity on onion and melon, which indicates its great potential as an inoculum. Full article

Plant height is a vital agronomic trait for crops, including oilseed crops such as rapeseed (Brassica napus L.). It affects the crop yield, oil content, and lodging resistance in rapeseed. In this study, we investigated a dwarf trait controlled by a semi-dominant allele in rapeseed. A dwarf line, YA2016-12, was crossed with a tall line, G184-189, and an F₂ population was established. Forty of the tallest plants and 40 of the shortest plants from the F₂ population were selected and two DNA pools (tall and dwarf) were constructed by the bulked segregant analysis (BSA) method. The two DNA pools and two parental DNAs were then re-sequenced. A sliding window analysis was used to calculate the Δ(SNP-index) and discover an association region on chromosome A03 with a length of 12.4 Mb. Within this region, we found 1225 genes, including 811 genes with non-synonymous or frameshift mutations between YA2016-12 and G184-189. Alignment to known plant height-related orthologs in Arabidopsis thaliana, as well as KEGG pathway and gene ontology annotations, was used to identify nine candidate genes (BnaA03g31770D, BnaA03g37960D, BnaA03g24740D, BnaA03g40550D, BnaA03g26120D, BnaA03g35130D, BnaA03g42350D, BnaA03g25610D, and BnaA03g39850D) involved in gibberellin or cytokinin signaling. Identification of the causal gene for this trait, and of genetic markers linked to favorable alleles, has potential utility for marker-assisted selection to breed rapeseed varieties with improved height. Full article

The introduction of nanofertilizers (Nfs) in agriculture has allowed the development of new technologies that enhance the productivity of crops. Within the most studied Nfs we find metal oxides, especially ZnO; however, the results of various experiments provide contradictory data on the growth variables. Therefore, this study intended to evaluate the efficiency associated with the use of nanoparticles, sulfates, and zinc-chelates in Phaseolus vulgaris L. cv. Strike grown in acid soil, as well as to evaluate its production, total biomass, and nitrogen assimilation. Phaseolus vulgaris L. cv. Strike plants were sprouted and grown in polyethylene bags containing 3 kg of acid soil (pH 6.8) in an experimental greenhouse and were watered with a nutritious solution. A completely randomized design including ten treatments and five repetitions was used. Treatments consisted of applying different zinc sources (sulfate, DTPA chelate, and zinc oxide nanoparticles) to four different doses (0, 25, 50, and 100 ppm of zinc). Results obtained indicated that the doses best favoring an increase in biomass, production, and nitrogen assimilation were 50 ppm of ZnSO₄, 100 ppm of DTPA-Zn, and 25 ppm of zinc oxide nanofertilizers (NfsOZn). Hence, the dose containing 25 ppm of NfsOZn was the most efficient dose, since at a lower dose it was able to equalize biomass accumulation, production, and nitrogen assimilation as compared to ZnSO₄ and DTPA-Zn sources. However, further research is required, given that high-concentration doses were toxic for beans. Finally, it is worth highlighting that zinc oxide nanoparticles have a huge potential to be used as nanofertilizers if applied in optimal concentrations. Full article

Phosphorus is an essential macronutrient required for plant growth and development. It is central to many biological processes, including nucleic acid synthesis, respiration, and enzymatic activity. However, the strong adsorption of phosphorus by minerals in the soil decreases its availability to plants, thus reducing the productivity of agricultural and forestry ecosystems. This has resulted in a complete dependence on non-renewable chemical fertilizers that are environmentally damaging. Alternative strategies must be identified and implemented to help crops acquire phosphorus more sustainably. In this review, we highlight recent advances in our understanding and utilization of soil microbes to both solubilize inorganic phosphate from insoluble forms and allocate it directly to crop plants. Specifically, we focus on arbuscular mycorrhizal fungi, ectomycorrhizal fungi, and phosphate-solubilizing bacteria. Each of these play a major role in natural and agroecosystems, and their use as bioinoculants is an increasing trend in agricultural practices. Full article

Agricultural scientists face the dual challenge of breeding input-responsive, widely adoptable and climate-resilient varieties of crop plants and developing such varieties at a faster pace. Integrating the gains of genomics with modern-day phenomics will lead to increased breeding efficiency which in turn offers great promise to develop such varieties rapidly. Plant phenotyping techniques have impressively evolved during the last two decades. The low-cost, automated and semi-automated methods for data acquisition, storage and analysis are now available which allow precise quantitative analysis of plant structure and function; and genetic dissection of complex traits. Appropriate plant types can now be quickly developed that respond favorably to low input and resource-limited environments and address the challenges of subsistence agriculture. The present review focuses on the need of systematic, rapid, minimal invasive and low-cost plant phenotyping. It also discusses its evolution to modern day high throughput phenotyping (HTP), traits amenable to HTP, integration of HTP with genomics and the scope of utilizing these tools for crop improvement. Full article

The goal of this paper is to show that logistic regression is an analytical method of interest to evaluate the marketability of different pepper (Capsicum annuum L.) cultivars. Two studies were conducted on “Italian sweet” pepper cultivars. Fruit samples were introduced in storage chambers and kept at 9 °C and 85–95% relative humidity during the study period. The fruits were evaluated individually and periodically by measuring the deterioration of fruit quality (rot, ageing, etc.). In this study, categorical explanatory variables (rot, etc.) and continuous explanatory variables (days of storage) were integrated and combined to determine the probability of marketability of the fruit. The results show that the binary logistic model is a useful statistical tool to analyse together both categorical and continuous variables in the study of the marketability of pepper cultivars. Full article

Increasing soil carbon stocks in agricultural grasslands has a strong potential to mitigate climate change. However, large uncertainties around the drivers of soil respiration hinder our ability to identify management practices that enhance soil carbon sequestration. In a context where more intense and prolonged droughts are predicted in many regions, it is critical to understand how different management practices will temper drought-induced carbon losses through soil respiration. In this study, we compared the impact of changing soil volumetric water content during a drought on soil respiration in permanent grasslands managed either as grazed by dairy cows or as a mowing regime. Across treatments, root biomass explained 43% of the variability in soil respiration (p < 0.0001). Moreover, analysis of the isotopic composition of CO₂ emitted from the soil, roots, and root-free soil suggested that the autotrophic component largely dominated soil respiration. Soil respiration was positively correlated with soil water content (p = 0.03) only for the grazed treatment. Our results suggest that the effect of soil water content on soil respiration was attributable mainly to an effect on root and rhizosphere activity in the grazed treatment. We conclude that farm management practices can alter the relationship between soil respiration and soil water content. Full article

Drought is one of the most harmful environmental stresses affecting the physiological, biochemical processes and growth of plants. Lucerne or alfalfa (Medicago sativa L.), one of the most popular pasture species in arid and semi-arid regions, plays a critical role in sustaining agricultural systems in many areas of the world. In order to evaluate the effect of water shortage on water status, biomass distribution and proline content, the relative water content (RWC), biomass and proline concentration in the leaves, stems and roots of lucerne seedlings under three different water regimes were studied in pots under a rainout shelter. The results showed that after water was withheld, the RWC of the different organs decreased significantly; at the same soil water content, the leaf RWC was higher than that of the stem and root. The biomass of the leaves, stems and roots were all reduced by water stress, while the root–shoot ratio increased indicating that the roots were less affected than the leaves and stems. Proline concentration increased with decreasing soil water content with the leaf proline concentration increasing more than that of stems and roots. These results indicate that roots of lucerne seedlings show greater resilience to water deficits than shoots. Full article

Sorption could be a way to concentrate nutrients in diluted waste streams to bring more nutrients back to agriculture. However, the sorbed nutrients must be plant available. The aim of this work was to investigate how plant available nitrogen (N) added sorbed to zeolite and is compared to conventionally added N. First, ¹⁵N labelled ammonium was sorbed to a sorbent, zeolite, in an aqueous solution. Then, the fertilizer effect was compared to the ammonium fertilizer and added the conventional way, with and without zeolite. A pot experiment with two soil types (chernozem and sandy soil) and wheat as test crop was used. Results indicated that the fertilizer effect of sorbed ammonium in the first growth cycle is about 50% of ammonium added conventionally. The sorbent itself had a positive effect in sandy soil, but not in chernozem. N uptake without added N was higher in chernozem than in sandy soil and more N from fertilizer was left in the soil after the experiment in the chernozem than in the sandy soil. In conclusion, ammonium added sorbed is plant available to some extent, but less so than conventionally added ammonium. Full article

This review deals with the main mechanisms of action exerted by antagonistic bacteria, such as competition for space and nutrients, suppression via siderophores, hydrolytic enzymes, antibiosis, biofilm formation, and induction of plant resistance. These mechanisms inhibit phytopathogen growth that affects postharvest fruit since quality and safety parameters are influenced by the action of these microorganisms, which cause production losses in more than 50% of fruit tree species. The use of synthetic fungicide products has been the dominant control strategy for diseases caused by fungi. However, their excessive and inappropriate use in intensive agriculture has brought about problems that have led to environmental contamination, considerable residues in agricultural products, and phytopathogen resistance. Thus, there is a need to generate alternatives that are safe, ecological, and economically viable to face this problem. Phytopathogen inhibition in fruit utilizing antagonist microorganisms has been recognized as a type of biological control (BC), which could represent a viable and environmentally safe alternative to synthetic fungicides. Despite the ecological benefit that derives from the use of controllers and biological control agents (BCA) at a commercial level, their application and efficient use has been minimal at a global level. Full article

Developing disease models to simulate and analyse yield losses for various pathogens is a challenge for the crop modelling community. In this study, we developed and tested a simple method to simulate septoria tritici blotch (STB) in the Cropsim-CERES Wheat model studying the impacts of damage on wheat (Triticum aestivum L.) yield. A model extension was developed by adding a pest damage module to the existing wheat model. The module simulates the impact of daily damage on photosynthesis and leaf area index. The approach was tested on a two-year dataset from Argentina with different wheat cultivars. The accuracy of the simulated yield and leaf area index (LAI) was improved to a great extent. The Root mean squared error (RMSE) values for yield (1144 kg ha⁻¹) and LAI (1.19 m² m⁻²) were reduced by half (499 kg ha⁻¹) for yield and LAI (0.69 m² m⁻²). In addition, a sensitivity analysis of different disease progress curves on leaf area index and yield was performed using a dataset from Germany. The sensitivity analysis demonstrated the ability of the model to reduce yield accurately in an exponential relationship with increasing infection levels (0–70%). The extended model is suitable for site specific simulations, coupled with for example, available remote sensing data on STB infection. Full article

A Multi-parent Advanced Generation Intercross (MAGIC) tomato population was developed by crossing eight founder lines chosen to include a wide range of variability. The lines were previously genotyped by a genotyping by sequencing approach. The MAGIC population was used to develop genotypes with important agronomic traits and to perform the Participatory Plant Breeding (PPB). Among the 400 plants of generation 4 (G4) of the MAGIC population cultivated in an organic field experiment, 22 individuals were phenotypically selected and a molecular analysis was done for both presence of resistance genes and fruit shape (marker assisted selection) on G5 seedlings. Three selected plants showed both the pyramiding gene of resistance to the main diseases and the ovate gene for pear shape typology. The 400 G10 stable lines that obtained from single seed descent will represent an important genetic resource for the tomato scientific community. The MAGIC population G4 was also cultivated in three organic farms located in North, Central and South Italy to carry out the PPB. The plants showed significant phenotypic differences in development, productivity and fruit color. This variability was used to select families of tomato adapted to low input crop management, different environments, agricultural practices and market conditions. Full article

When drought occurs during the soybean (Glycine max L. Merr.) sowing period, emergence will most likely be affected. We evaluated a diverse panel of 373 plant introductions under controlled environmental conditions for primary root length (PRL) (at 100, 80, 60, 40, and 20% pot water holding capacity (PWHC); pots filled with potting soil that contained Sphagnum peat moss (>50%), bark, and perlite), and time taken for radicle emergence (TRE). The PRL decreased ≥75% at 40% PWHC, compared to 100, 80, and 60% PWHC. No genotypes germinated at 20% PWHC. We identified superior genotypes in terms of PRL and TRE, and found a positive relationship between PRL and emergence that became stronger with decreases in soil moisture levels. This indicates the importance of PRL in improving emergence, which becomes greater with decreases in soil moisture levels or increases in severity of drought. Seed weight was not related to PRL and emergence, indicating that larger seeds will not necessarily have longer PRL and better emergence. As the soybean panel used in this study was previously assessed for traits associated with drought tolerance at the late-vegetative and flowering stages, and the present study assessed it for putative traits related with emergence under various soil moisture conditions, the panel will become an important resource for soybean improvement. Full article

Pre-harvest sprouting (PHS) is one of the most important factors having adverse effects on yield and grain quality all over the world, particularly in wet harvest conditions. PHS is controlled by both genetic and environmental factors and the interaction of these factors. Breeding varieties with high PHS resistance have important implications for reducing yield loss and improving grain quality. The rapid advancements in the wheat genomic database along with transcriptomic and proteomic technologies have broadened our knowledge for understanding the regulatory mechanism of PHS resistance at transcriptomic and post-transcriptomic levels. In this review, we have described in detail the recent advancements on factors influencing PHS resistance, including grain color, seed dormancy, α-amylase activity, plant hormones (especially abscisic acid and gibberellin), and QTL/genes, which are useful for mining new PHS-resistant genes and developing new molecular markers for multi-gene pyramiding breeding of wheat PHS resistance, and understanding the complicated regulatory mechanism of PHS resistance. Full article

Under field conditions, plants need to optimize nutrient ion and water acquisition in their fluctuating environment. One of the most important variables involved in variations of ion uptake processes is temperature. It modifies the thermodynamic processes of root uptake and ion diffusion in soil throughout day–night and ontogenetic cycles. Yet, most models of nitrogen (N) uptake in plants are built from set values of microscopic kinetic parameters, V_m and K_m, derived from a Michaelis–Menten (MM) interpretation of nutrient isotherms. An isotherm is a curve depicting the response of root nitrate influx to external nitrate concentrations at a given temperature. Models using the MM formalism are based on several implicit assumptions that do not always hold, such as homothetic behavior of the kinetic parameters between the different root biological scales, i.e., the epidermis cell, root segments, root axes, and the whole root system. However, in marine phytoplankton, it has been clearly demonstrated that the macroscopic behavior in the nutrient uptake of a colony cannot be confounded with the microscopic behavior of individual cells, due to the cell diffusion boundary layer. The same is also true around plant root segments. Improved N uptake models should either take into account the flexibility of the kinetic parameters of nitrate uptake at the cellular level (porter–diffusion approach) or use the more realistic macroscopic kinetic parameters proposed by the flow–force approach. Here we present recent solutions proposed in marine phytoplankton and plant nutrient uptake models to make a more flexible description of the nutrient ion uptake process. Use of the mechanistic porter–diffusion approach developed in marine phytoplankton introduces more flexibility in response to cell characteristics and physical processes driven by temperature (diffusion and convection). The thermodynamic flow–force interpretation of plant-based nutrient uptake isotherms introduces more flexibility in response to environmental cues and root aging. These two approaches could help solve many problems that modelers encounter in these two research areas. Full article