Plant Nutritional Quality Research Articles

Salicylic acid and nutrient sprays to improve apple fruit quality

Maturity at harvest is one of the most important properties that determine the final quality of the apple fruit. Appearance, texture, flavour and nutritional value are qualities that consumers evaluate empirically to decide whether to eat the fruit again. Within agricultural practices in and out of the orchard, the relationship between plant nutrition and fruit quality is important, and proper nutrient balance is essential to maintain fruit quality. This research work was carried out on ‘Golden Delicious’ and ‘Red Chief’ apple trees. A 56 factorial arrangement was used, with 5 concentrations and 6 factors, 25 treatments in a Taguchi L25 structure. Improvements were found in parameters for fruit finish and fruit quality. The factors with the greatest positive effect on quality in order of importance were Salicylic Acid (SA) 1.0 mM, Potassium (K) 58.90 mM, Molybdenum (Mo) 0.516 mM, Calcium (Ca) 70.00 mM and Cobalt (Co) 8.248 mM and in order of importance the following variables: TSS/acidity ratio, total soluble solids TSS, antioxidant capacity (AC), total phenols (TF), and titratable acidity (TA) in ‘Golden Delicious’ apple. Considering ‘Red Chief’, the factors Ca 70.00 mM, K 58.79 mM and SA 1.0 mM, with the variables; TA, TSS/acidity ratio, TF, TSS and AC that finally lead to an optimal development of finish and quality in the apple fruit.

No evidence for the simultaneous induction of structural and chemical defences in spiny southern African savanna trees

AbstractIt is still not well established whether plant chemical and physical defence traits can be simultaneously induced in savanna trees and how this would affect plant nutritional quality. Here, we use a long‐term mammalian herbivore exclosure experiment in a dystrophic semi‐arid African savanna to test how chemical (condensed tannins [CTs] and total polyphenols [TPs]) and structural (spines and thorns) defences are affected by herbivore exclusion in five common savanna woody species. We also tested whether nutritional quality interacted with either physical or chemical defences after protected trees were reintroduced to herbivores. Trees that remained available to herbivores did not increase CTs and TPs, rather these were found to be higher without mammalian herbivory in some species. In contrast, herbivory resulted in a significant induction of structural defences (i.e. longer and thicker spines) and at the same time, improved nutritional quality (i.e. higher available crude protein and lower C:N ratios) for some species. We found that the plant defence traits of the treatment which previously excluded herbivores were mostly similar to the control, which both differed from the exclosure, suggesting that legacies of herbivore exclusion on plant defence traits are mostly short‐lived.

Production and King Grass Nutritional Quality Number of Sources of Nitrogen Fertilizer

The aim of this study was to obtain the best nitrogen source and level of information on plant growth, production, and nutritional quality of king grass forage (Pennisetum Purpureophoides). The source of nitrogen comes from natural fertilizers (chicken and cow manure) and artificial fertilizers (urea and NPK). The method was completely randomized with the BNJ further test with a confidence interval of <0.05. The research plan consisted of 2 factors: the type of fertilizer (organic; cow and chicken manure); inorganic fertilizers (NPK and urea + nitrogen); and the second factor, the dosage (50, 75, and 100 kg/ha/defoliation). Observation parameters were plant height, stem diameter, number of plants per clump, fresh forage production, dry matter production, dry matter content, crude protein content, crude fibre content, and crude fat content. The results of the study using modifications in fertilizing king grass to increase carbon sources and nutrients obtained significant results. The average plant height was obtained between 60-263 cm. The largest size was at defoliation 1, and the lowest was at defoliation 4. Plant diameter increased between 9.97–12.43 mm, with tiller production in plants increasing to 18.5–25.8 planting. The increase was also followed by the number of fresh leaves and a decrease in the number of dry leaves. Protein content increased with the higher dose given at 11.78% BK, with a crude fiber value of 34.41% BK. King Grass contains a good source of carbon nutrients and can affect the increase in plant growth with a higher plant height and a higher number of leaves. Doi: 10.28991/HIJ-2022-03-03-02 Full Text: PDF

Influence of Organic and Inorganic Fertilizer Regimes on Growth Patterns and Antioxidants Capacity of Strawberry (Fragaria × Ananassa Duch.) cv. Chandler

Fertilization, either in the form of organic or inorganic, always affects plant growth, yield, and nutritional quality of fruit crops. Further, the efficacy of fertilizers depends on various factors, including the area, climatic conditions, and cultivars. Rawalakot has ideal climatic conditions for growing strawberries. However, no studies related to the impact of different soil amendments on the growth habit and fruit quality of strawberries have been conducted so far. Therefore, in this study, different combinations of organic (farmyard manure (FYM) and poultry manure (PM)) and inorganic (urea) (N 150 kg/ha) fertilizers were used for comparison of growth pattern and postharvest quality of strawberry cv. Chandler. The organic and inorganic fertilizer regimes showed comparatively better results in terms of all the parameters studied. However, plants grown on soils amended with FYM equivalent to 75 kg N per ha + PM equivalent to 75 kg N per ha and FYM equivalent to 50 kg N per ha + PM equivalent to 50 kg N per ha + urea 50 kg N per ha showed 41% and 28% more survival percentage compared to control. Furthermore, the number of leaves, number of flowers, number of fruits, and yield were significantly high in plants grown on amended soil. Moreover, a significantly high amount of total soluble solids (10.0°Brix), titratable acidity (1.18%), ash (0.84%), fiber (3.03%), total phenols (7.61 μg gallic acid/g fresh weight), total flavonoids (7.93 mmol quercetin/100 g fresh weight), and total antioxidants (0.60 activity of FeSO4 mg/g fresh weight) was noted in comparison with control. Similarly, a combined treatment of FYM, PM, and urea also showed good results in terms of all the growth and fruit quality parameters as compared with other fertilizer regimes as well as control. However, the overall results of this study revealed that strawberries grown on soil amended with a combined dose of FYM equivalent to 75 kg N per ha + PM equivalent to 75 kg N per ha could be a potential dose for maximum yield and better quality fruits of strawberry.

Plant Water Stress Reduces Aphid Performance: Exploring Mechanisms Driven by Water Stress Intensity

Drought alters plant traits in ways that affect herbivore performance. However, we lack a comprehensive understanding of the plant-derived mechanisms that mediate insect responses to drought. Water stress occurs along gradients of intensity, and the impacts of drought intensity on plant-insect interactions is understudied. Here, we assessed aphid performance on wheat plants exposed to a gradient of water stress and measured plant nutrients and phytohormones that may mediate aphid response to drought. We show that water stress reduced aphid performance, and the negative effect grew stronger as the magnitude of water stress increased. The plant response to water limitation was not consistent across the stress gradient and was reliant on the trait measured. Water limitation did not affect whole-plant nitrogen; however, water limitation did reduce amino acid concentration and increase sugars, but only under high stress intensity. The phytohormones abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA), and the expression of their associated gene transcripts, were also differentially affected by water stress intensity. In well-watered conditions, aphid feeding increased concentrations of the defense-related hormones SA and JA over time; however, any amount of water limitation prevented aphid induction of JA. Although aphids may experience a reprieve from JA-related defenses in stressed conditions, SA levels remain high in response to aphid feeding, indicating aphids are still vulnerable to SA-related defenses. Any level of water stress also increased the expression of a callose-associated gene transcript, a physical defense that impairs feeding. Thus, poor aphid performance on mildly-stressed plants was correlated with increased plant defenses, whereas poor performance on highly-stressed plants was correlated with stronger plant defense induction and reduced plant nutritional quality. Understanding the mechanisms driving aphid and plant performance under water stress conditions can improve our ability to predict how aphid populations will respond to climate change.

Trichoderma harzianum Suşlarının Domates Fide Kalitesine Etkileri

This study was conducted to determine the effects of Trichoderma harzianum on seedling growth and quality as two consecutive experiments during the spring months of 2018. In the first experiment, four different T. harzianum strains and a commercial preparate were used by adding into seed sowing substrate and compared with control group which had no treatment. The most promising strain (strain2), was used with and without foliar fertilizer (20:20:20) and foliar fertilizer itself was considered as control. Emergence period and rate were determined to observe the effects of treatments of germination of seeds. Regarding the seedling growth and quality, seedling length, root length, hypocotyl diameter, leaf thickness, fresh and dry weights of root and shoots, dry matter content, color, chlorophyll index, leaf macro and micro plant nutrient contents and seedling quality index were determined at the planting stage. Data obtained from the first experiment showed that the effects of T. harzianum strains on seedling morphology, physiology and nutrient content were different. Among the tested strains, strain2 showed better performance on seedling length, root and shoot dry matter contents, total fresh weight, chlorophyll, a color value and P, Ca, Mn, Cu and Zn contents of leaves and improved seedling quality. The second experiment result showed that the foliar fertilizer application increased the efficiency of T. harzianum strain2. T. harzianum strain2 without foliar fertilizer remained below the control treament in all measured parameters. When all the data were evaluated together, it was concluded that T. harzianum could be used to increase seedling quality due to its positive effects on seedling biomass, plant nutrition uptake and quality index. Moreover, it can be used in organic seedling production as alternative biostimulant.

Recent Developments to Mitigate Selenium Deficiency in Agricultural Eco-Systems

Under changing climate, trace elements like selenium (Se) have emerged as vital constituent of agro-ecosystems enabling crop plants to off-set the adverse effects of suboptimal growth conditions. The available form of selenium is important for boosting its bioavailability to crop plants having varied agro-botanical traits and root architectural systems. As compared to selenite, the selenate has a weaker soil bonding, higher absorption in the soil solution which results in a comparatively absorption by plant roots. Various factors including dry climate, high pH, optimal ambient air temperature, less accumulation of water, and low concentration of organic matter in the soil tend to boost the selenate ratio in the soil. The use of selenium pelleted seeds has emerged as an interesting and viable alternative to alleviate selenium deficiency in agricultural eco-systems. Similarly, the co-inoculation of a mixture of Selenobacteria and Arbuscular mycorrhizal fungi represents an evolving promising strategy for the bio-fortification of wheat plants to produce selenium-rich flour to supplement human dietary needs. Furthermore, in-depth research is required to assure the effectiveness of biological fertilization procedures in field conditions as well as to explore and increase our understanding pertaining to the underlying main mechanisms and channels of selenium absorption in plants. The focus of this review is to synthesize the recent developments on Se dynamics in soil-plant systems and emerging promising strategies to optimize its levels for crop plants. Recent developments regarding the use of micro-organisms as a biotechnological mean to enhance plant nutrition and crop quality have been objectively elaborated. The study becomes even more pertinent for arid and semi-arid agro-ecosystems owing to the potential role of selenium in providing stress tolerance to crop plants. Moreover, this review synthesizes and summarizes the recent developments on climate change and bioavailability, and the protective role of selenium in crop plants.

Mapping canopy nitrogen-scapes to assess foraging habitat for a vulnerable arboreal folivore in mixed-species Eucalyptus forests.

Herbivore foraging decisions are closely related to plant nutritional quality. For arboreal folivores with specialized diets, such as the vulnerable greater glider (Petauroides volans), the abundance of suitable forage trees can influence habitat suitability and species occurrence. The ability to model and map foliar nitrogen would therefore enhance our understanding of folivore habitat use at finer scales. We tested whether high‐resolution multispectral imagery, collected by a lightweight and low‐cost commercial unoccupied aerial vehicle (UAV), could be used to predict total and digestible foliar nitrogen (N and digN) at the tree canopy level and forest stand‐scale from leaf‐scale chemistry measurements across a gradient of mixed‐species Eucalyptus forests in southeastern Australia. We surveyed temperate Eucalyptus forests across an elevational and topographic gradient from sea level to high elevation (50–1200 m a.s.l.) for forest structure, leaf chemistry, and greater glider occurrence. Using measures of multispectral leaf reflectance and spectral indices, we estimated N and digN and mapped N and favorable feeding habitat using machine learning algorithms. Our surveys covered 17 Eucalyptus species ranging in foliar N from 0.63% to 1.92% dry matter (DM) and digN from 0.45% to 1.73% DM. Both multispectral leaf reflectance and spectral indices were strong predictors for N and digN in model cross‐validation. At the tree level, 79% of variability between observed and predicted measures of nitrogen was explained. A spatial supervised classification model correctly identified 80% of canopy pixels associated with high N concentrations (≥1% DM). We developed a successful method for estimating foliar nitrogen of a range of temperate Eucalyptus species using UAV multispectral imagery at the tree canopy level and stand scale. The ability to spatially quantify feeding habitat using UAV imagery allows remote assessments of greater glider habitat at a scale relevant to support ground surveys, management, and conservation for the vulnerable greater glider across southeastern Australia.

Interactions of gall-formers and leaf-chewers on a tropical tree fern: evidence for non-repulsion and co-occurrence between insect guilds.

Host plant selection by herbivores is driven by a complex array of cues, including leaf traits and previous leaf damage. Herbivore-associated cues to host selection at the plant and leaf scale aid understanding of mechanisms responsible for host preference that might translate into increased performance, as well as processes structuring herbivore populations mediated by interactions. We investigated how changes induced by a galling insect in the tropical fern Cyathea phalerata act as repellent or attractant cues for sawfly feeding and the effects of leaf size on herbivory levels. We recorded gall abundance, damage by chewers, leaf size, plant nutritional quality, phenolic concentration and leaf anatomical traits between galled and non-galled leaf samples. Galled samples contained less N, higher levels of phenolics and higher C/N ratio. However, leaf-chewing damage did not differ between galled and non-galled leaves. The gall structure was avoided by chewers, as it had high concentrations of phenolics, lignification and suberization. Larger leaves sustained higher gall abundance, but leaf size did not have a significant effect on chewer damage. A co-occurrence index calculated for both guilds indicated that galls and chewers exhibited a distribution that did not differ from random, reinforcing that the two guilds on C. phalerata do not show patterns of repulsion such as those maintained by interspecific competition. Sawflies dismissing chemical cues indicate that the increase in phenolics caused by galling insects does not generate increased protection of the galled pinnules. Our results highlight ferns as key resources for herbivores and as a potential plant group to study new research avenues on plant-insect interactions.

Genome-wide microsatellites in amaranth: development, characterization, and cross-species transferability

The online version contains supplementary material available at 10.1007/s13205-021-02930-5.

Feeding guild determines strength of top-down forces in multitrophic system experiencing bottom-up constraints

Nitrogen (N) and water are crucial in crop production but increasingly scarce environmental resources. Reducing their inputs can affect the whole plant-arthropod community including biocontrol agents. In a multitrophic system, we studied the interaction of the bottom-up effects of moderately reduced N concentration and/or water supply as well as the top-down effects of pests of different feeding guilds on plant nutritional quality (N and carbon concentration), direct defense (alkaloids and phenolics), and indirect defense (plant volatile organic compounds); on herbivore performance and host quality (N and carbon) to parasitoids and the latter's performance. Studied organisms were tomato plants, the sap feeders Macrosiphum euphorbiae and Bemisia tabaci, the leaf chewers Tuta absoluta and Spodoptera littoralis, and the parasitic wasps Aphelinus abdominalis and Necremnus tutae. Resource limitation affected plant quality, triggering bottom-up effects on herbivore and parasitoid performance, except for T. absoluta and N. tutae. Feeding guild had a major influence: bottom-up effects were stronger on sap feeders; N effects were stronger on sap feeders while water effects were stronger with leaf chewers (S. littoralis). Top-down effects of leaf chewer herbivory partly attenuated bottom-up effects and partly suppressed plant defenses. Bottom-up effects weakened when cascading up trophic levels. In summary, the interaction between plants, pests, and beneficial insects was modulated by abiotic factors, affecting insect performance. Simultaneous abiotic and biotic impact shaped plant biochemistry depending on the feeding guild: the biotic top-down effect of leaf chewer herbivory attenuated the bottom-up effects of plant nutrition and hence dominated the plant biochemical profile whereas in sap feeder infested leaves, it corresponded to the abiotic impact. This study highlights the plant's finely tuned regulatory system facilitating response prioritization. It offers perspectives on how smart manipulation of plant nutrient solutions might save resources while maintaining efficient biocontrol in crop production.

Intentional and unintentional selection during plant domestication: herbivore damage, plant defensive traits and nutritional quality of fruit and seed crops.

Greater susceptibility to herbivory can arise as an effect of crop domestication. One proposed explanation is that defenses decreased intentionally or unintentionally during the domestication process, but evidence for this remains elusive. An alternative but nonexclusive explanation is presumed selection for higher nutritional quality. We used a metaanalytical approach to examine susceptibility to herbivores in fruit and seed crops and their wild relatives. Our analyses provide novel insights into the mechanisms of increased susceptibility by evaluating whether it can be attributed to either a reduction in herbivore defensive traits, including direct/indirect and constitutive/inducible defenses, or an increase in the nutritional content of crops. The results confirm higher herbivory and lower levels of all types of defenses in crops compared to wild relatives, although indirect defenses were more affected than direct ones. Contrary to expectations, nutritional quality was lower in crops than in wild relatives, which may enhance biomass loss to herbivores if they increase consumption to meet nutritional requirements. Our findings represent an important advance in our understanding of how changes in defensive and nutritional traits following domestication could influence, in combination or individually, crop susceptibility to herbivore attacks.

The Use of Biostimulants in Sustainable Viticulture

Viticulture has a very wide application area in the world, which is great importance economically and in terms of human diet. The grapevine is evaluated in many areas, both grapes and leaves contain valuable compounds such as vitamins, minerals, antioxidants, organic acids, fats, proteins etc.. It has become inevitable that sustainable production techniques, the use of new integrated techniques, and sufficient sensitivity to protect human and environmental health have to be applied for viticulture which is of great importance in terms of human diet. Sustainable viticulture includes human and environment friendly production systems. It is seen that biostimulants, in other words bioactivators, are used within the scope of scientific researches and in viticulture applications in sustainable viticulture in the world. Containing organic or inorganic compounds, microorganisms; biostimulants are applicable to leaves, soil or seeds; positively affect plant growth, yield, nutrition, and product quality. It has been determined by various studies that biostimulants increase the resistance of plants to biotic and abiotic stress conditions and also regulates the soil structure. Biostimulants have been classified by some researchers as humic substances, amino acids and other nitrogenous compounds, seaweed and plant extracts, chitin and chitosan-like polymers, inorganic compounds, beneficial fungi and beneficial bacteria, waste, exudates and extracts of seeds, leaves and roots. Biostimulants have an important place within the scope of sustainable viticulture in areas such as protection of natural resources, especially soil and water, combating erosion and forest fires, ensuring biological diversity, and integrated pest management. The need to increase soil and plant productivity, to create ecological balance, and most importantly to protect the health of humans and other living things, is better seen each day. This need for a sustainable life and healthy continuity of future generations leads scientists and producers to friendly applications such as biostimulants.

Plant Growth and Nutritional Quality Attributes of Basella alba Applied with Variable Rates of Nitrogen Fertilizer at Different Planting Dates under Canadian Maritime Climatic Conditions

Nitrogen (N) fertilization at critical planting time is important to optimize productivity and reduce nitrate accumulation in edible portions of green leafy vegetable plants. A field experiment was performed to determine the effects of variations in N rate and planting time on plant growth, yield, and nutritional quality attributes of Basella alba under Atlantic maritime climatic conditions. The N rates were 0 (control), 40 (low), 80 (medium), and 120 kg ha−1 (high) at planting times 15 June–3 August (early season), 6 July–20 August (mid-season), and 4 August–8 September (late season). Plant height, number of branches, and stem girth were increased after 45 days after sowing in early and mid-season plantings, but leaf length decreased during the same time by 32.8% in the late planting. The average yield obtained in early, mid-, and late plantings were 171, 464, and 328 g plant−1, respectively. Low N gave the highest yield in early planting while medium N gave higher yields in mid- and late plantings. However, the medium N increased nitrate accumulation in B. alba by 7% compared to the high N rate. In general, there was no significant effect of N on B. alba total phenolic and total carotenoid contents. Overall, the highest yield was obtained during the warmest summer months of mid- and late plantings. Therefore, there is a potential to grow B. alba as a summer vegetable under Canadian Atlantic maritime conditions. However, it is recommended to reduce the rate of N fertilizer application during high-temperature conditions. Future studies are required to investigate phosphorus and potassium fertilization and nitrate accumulation in B. alba and potential health risks.

Comparative Metabolite Profile, Biological Activity and Overall Quality of Three Lettuce (Lactuca sativa L., Asteraceae) Cultivars in Response to Sulfur Nutrition.

The main objective of the present study was to assess the effects of sulfur (S) nutrition on plant growth, overall quality, secondary metabolites, and antibacterial and radical scavenging activities of hydroponically grown lettuce cultivars. Three lettuce cultivars, namely, Pazmanea RZ (green butterhead, V1), Hawking RZ (green multi-leaf lettuce, V2), and Barlach RZ (red multi-leaf, V3) were subjected to two S-treatments in the form of magnesium sulfate (+S) or magnesium chloride (−S). Significant differences were observed under −S treatments, especially among V1 and V2 lettuce cultivars. These responses were reflected in the yield, levels of macro- and micro-nutrients, water-soluble sugars, and free inorganic anions. In comparison with the green cultivars (V1 and V2), the red-V3 cultivar revealed a greater acclimation to S starvation, as evidenced by relative higher plant growth. In contrast, the green cultivars showed higher capabilities in production and superior quality attributes under +S condition. As for secondary metabolites, sixteen compounds (e.g., sesquiterpene lactones, caffeoyl derivatives, caffeic acid hexose, 5-caffeoylquinic acid (5-OCQA), quercetin and luteolin glucoside derivatives) were annotated in all three cultivars with the aid of HPLC-DAD-MS-based untargeted metabolomics. Sesquiterpene lactone lactucin and anthocyanin cyanidin 3-O-galactoside were only detected in V1 and V3 cultivars, respectively. Based on the analyses, the V3 cultivar was the most potent radical scavenger, while V1 and V2 cultivars exhibited antibacterial activity against Staphylococcus aureus in response to S provision. Our study emphasizes the critical role of S nutrition in plant growth, acclimation, and nutritional quality. The judicious-S application can be adopted as a promising antimicrobial prototype for medical applications.

Metabolic Analysis of Root, Stem, and Leaf of Scutellaria baicalensis Plantlets Treated with Different LED Lights.

Light emitting diodes (LEDs) have recently been considered an efficient artificial light source in plant factories for enhancing plant growth and nutritional quality. Accordingly, this study aimed to review blue, red, and white LED light sources for efficiency and length of the growing period to produce seedlings of Scutellaria baicalensis with high nutritional value. The roots, stems, and leaves of S. baicalensis seedlings were grown under different LED lights and harvested after two and four weeks, and analyzed using high-performance liquid chromatography and gas chromatography time-of-flight mass spectrometry to identify and quantify primary and secondary metabolites. Roots, particularly in the seedlings treated with white LEDs were determined to contain the greatest concentrations of the representative compounds present in S. baicalensis: baicalin, baicalein, and wogonin, which show highly strong biological properties compared to the other plant organs. A total of 50 metabolites (amino acids, sugars, sugar alcohols, organic acids, phenolic acids, and amines) were detected in the roots, stems, and leaves of S. baicalensis seedlings, and the concentrations of primary and secondary metabolites were generally decreased with the increasing duration of LED illumination. Therefore, this study suggests that white LED light and a 2-week growing period are the most efficient conditions for the production of baicalin, baicalein, and wogonin.

Nanoparticles as Novel Elicitors to Improve Bioactive Compounds in Plants

Bioactive compounds (e.g., flavonoids, phenolics acids, alkaloids and carotenoids) are commercially-valued products, due to their wide array of applications in the medical, pharmacological, cosmetic, agriculture and food industry. A strategy applied to increase or enhancing bioactive compounds production in plants is controlled elicitation. In recent years, many researchers have studied the role of nanoparticles (NPs) as a novel elicitor for the biosynthesis of bioactive compounds shown that the NPs could affect the plant’s secondary metabolism in plant and culture systems. In this sense, recent studies have highlighted the potential applications of nanotechnology in crop production by improving the nutraceutical and nutritional quality of plants. In this review, we present studies about the application of NPs to enhance the production of bioactive plant metabolites. The aforementioned studies in ex vitro as in vitro, in addition to the effect of post-harvest by NPs application.

Comparison of Plant Morphology, Yield and Nutritional Quality of Fagopyrum esculentum and Fagopyrum tataricum Grown under Field Conditions in Belgium.

Buckwheat is a pseudocereal with high nutritional and nutraceutical properties. Although common buckwheat (Fagopyrum esculentum) is the main cultivated species, Tartary buckwheat (Fagopyrum tataricum) is gaining interest. In this paper, we compared plant growth, yield-related parameters and seed nutritional qualities of two varieties of F. esculentum and F. tataricum under field conditions in Belgium. Fagopyrum esculentum flowered earlier, produced less nodes, less branches, less inflorescences, but more flowers per inflorescence than F. tataricum. The yield was higher in F. tataricum, while the thousand-grain weight was higher in F. esculentum. Yield ranged between 2037 kg/ha and 3667 kg/ha depending on the species and year. Regarding nutritional qualities, seeds of F. esculentum contained more proteins (15.4% vs. 12.8%) than seeds of F. tataricum although their amino acid profile was similar. Seeds of F. esculentum contained also more Mg (1.36 vs. 1.15 mg/g dry weight (DW)) and less Fe (22.9 vs. 32.6 µg/g DW) and Zn (19.6 vs. 24.5 µg/g DW) than F. tataricum. The main difference between seed nutritional quality was the concentration of flavonoids that was 60 times higher in F. tataricum than in F. esculentum. Both species grow well under Belgian conditions and showed good seed quality.

Genomic Prediction Informed by Biological Processes Expands Our Understanding of the Genetic Architecture Underlying Free Amino Acid Traits in Dry Arabidopsis Seeds.

Plant growth, development, and nutritional quality depends upon amino acid homeostasis, especially in seeds. However, our understanding of the underlying genetics influencing amino acid content and composition remains limited, with only a few candidate genes and quantitative trait loci identified to date. Improved knowledge of the genetics and biological processes that determine amino acid levels will enable researchers to use this information for plant breeding and biological discovery. Toward this goal, we used genomic prediction to identify biological processes that are associated with, and therefore potentially influence, free amino acid (FAA) composition in seeds of the model plant Arabidopsis thaliana. Markers were split into categories based on metabolic pathway annotations and fit using a genomic partitioning model to evaluate the influence of each pathway on heritability explained, model fit, and predictive ability. Selected pathways included processes known to influence FAA composition, albeit to an unknown degree, and spanned four categories: amino acid, core, specialized, and protein metabolism. Using this approach, we identified associations for pathways containing known variants for FAA traits, in addition to finding new trait-pathway associations. Markers related to amino acid metabolism, which are directly involved in FAA regulation, improved predictive ability for branched chain amino acids and histidine. The use of genomic partitioning also revealed patterns across biochemical families, in which serine-derived FAAs were associated with protein related annotations and aromatic FAAs were associated with specialized metabolic pathways. Taken together, these findings provide evidence that genomic partitioning is a viable strategy to uncover the relative contributions of biological processes to FAA traits in seeds, offering a promising framework to guide hypothesis testing and narrow the search space for candidate genes.

Diagnose of Indigenous Arbuscular Mycorrhizal Communities Associated to Cynara cardunculus L. var. altilis and var. sylvestris.

Cynara cardunculus L. is a perennial species with high potential for bioenergy production. Arbuscular mycorrhizal symbiosis (AMF) is probably the terrestrial symbiosis most extended on earth. It presence in roots and soils improves plant nutrition and soil quality. Indigenous AMF have developed a variety of modifications to survive in their habitat and thus could serve as potential inoculants for the implantation of plant species in the respective AMF soil habitat. This work aimed to diagnose the status of the AMF symbiosis associated to two cardoon cultivars after a year of growth in a saline soil and in a conventional farming soil. For that purpose we determined AMF parameters in 4 rhizospheric soils and in roots of the cardoon varieties. We found that: (1) the rhizosphere of C. cardunculus var. altilis positively influenced the extraradical mycelium development in the saline soil, (2) the inorganic fertilization history of the conventional farming soil could have had a negative effect on the AMF community and, (3) the intraradical mycelium (IRM) development was extremely low. Our diagnosis suggests that, in order to improve the positive effects of AMF on cardoon growth and soil quality, efforts should be focused on the development of the IRM. In a boarder sense, the implementation of a diagnosis of indigenous AMF communities as a general agronomic practice could become an useful tool to farmers that are willing to potentiate the benefits of AMF on plant growth and soil quality.