Accumulation Of Mineral Nutrients Research Articles

Fluvial avulsions influence soil fertility in the Pantanal wetlands (Brazil)

River avulsions drive important changes in the Pantanal wetlands, owing to their role in the hydro-sedimentology of the region. Although relevant to numerous ecosystem services, few studies have analyzed the influence of river avulsions on soil fertility in the Pantanal. Here, we use the largest ongoing avulsion in the Taquari River (Caronal region) to evaluate the effects on soil fertility, considering two factors: avulsion stage (1) and aquatic-terrestrial succession (2). Since both factors are influenced by macrophyte abundance, an incident map was created through tasseled cap indices from Sentinel 2 images to guide sampling efforts in flooded soils. The mapped area was split into two zones of alluvial processes, the first from the apex of the Caronal lobe corresponding to the Taquari River megafan (TRM), and the second as the distal Paraguay River floodplain (PRF). Soil macro- and micronutrient levels were evaluated from 42 surface samples (0–0.2 m) distributed across the two alluvial process zones. The macrophyte map's overall accuracy (OA) was analyzed by a confusion matrix using the Sentinel 2 imagery. Finally, we used Random Forest regressions to determine the influence of response variables on soil attributes, including tassel indices, distance from the Caronal crevasse, macrophyte density, and an existing soil fertility map. The macrophyte map obtained an OA of 93 %. Some parameters such as pH (r = −0.62; R2 = 0.57), effective cation exchange capacity (r = −0.49; R2 = 0.79), Mn (r = −0.71; R2 = 0.6), Zn (r = −0.69; R2 = 0.54), and base saturation (r = −0.7; R2 = 0.93) were influenced by the distance or level of maturation of the avulsion stage in the TRM. Our scattering of soil collections was insufficient to test the terrestrialization hypothesis (2). The study results show that river channel avulsions influence the accumulation of mineral and organic nutrients in tropical floodplain soils, which has implications for fertility and biodiversity.

Potassium humate and cobalt enhance peanut tolerance to water stress through regulation of proline, antioxidants, and maintenance of nutrient homeostasis

Water stress is an important factor that substantially impacts crop production. As a result, there is a need for various strategies that can mitigate these negative effects. One such strategy is the application of potassium humate (Kh) and cobalt (Co), which have been reported to enhance the resistance of crop plants. Therefore, the present experiment was designed to investigate whether the application of Kh and Co could positively affect proline, chlorophyll and mineral elements contents, and antioxidant defense systems which in turn will mitigate the negative impact of water stress under different irrigation strategies. In 2021 and 2022, an open-field experiments were conducted by using a split-plot design. The main plots were divided to represent different irrigation strategies (ST), with additional control of full irrigation requirements (ST1). Four STs were implemented, with ST1, followed by the application of 75%, 50%, and 25% irrigation strategies in ST2, ST3, and ST4 respectively, in the next irrigation, followed by the full requirements, and so on. In the subplots, peanut plants were treated with tap water (Control), Kh at 2 g l−1 and 3 g l−1, Co, Co + Kh 2 g l−1 and Co + Kh 3 g l−1. The yield was negatively affected by the implementation of ST4, despite the increase in proline contents. Furthermore, there was a decrease in relative water content, chlorophyll content, antioxidant enzymes, protein, and mineral nutrient elements. However, the application of Kh or Co showed better improvements in most of the studied parameters. It is worth noting that there was an antagonistic relationship between Co and iron/manganese, and the intensity of this relationship was found to depend on the STs implemented. The highest mineral nutrient accumulation, chlorophyll content, relative water content, protein content, oil content, seed yield, and water productivity were observed when peanut plants were treated with Kh 3 g l−1 + Co under the ST2 water strategy.

Identification of novel germplasm and genetic loci for enhancing mineral element uptake in soybean

Bioavailability, uptake, and spatial distribution of essential and toxic mineral elements are pivotal factors that govern crop growth, development, and productivity. Soybean is a major leguminous crop globally, and yield losses are commonly attributed to various abiotic factors, including nutrient deficiencies or the influence of toxic minerals in the soil. Therefore, understanding the molecular basis of differential mineral element uptake, translocation, and accumulation in soybean is vital for developing improved cultivars. Here, we used portable X-ray fluorescence (p-XRF) for rapid and high-throughput mineral element profiling of a diverse set of soybean germplasm using leaves, stem, root, and seed tissues. Genome-wide association (GWAS) was performed on the element profiles of 219 soybean accessions, revealing lines with notable two to tenfold difference in various mineral nutrient uptake. These identified lines represent valuable genetic resources for germplasm development and gene discovery. The GWAS analysis pinpointed significant genomic loci and haplotypes associated with accumulation of aluminum (Al), silicon (Si), iron (Fe), and manganese (Mn). Remarkably, genes associated with the transport of solutes, metals, and ions have been pinpointed, indicating their potential involvement in the nutrient uptake and soybean improvement. To gain functional insights, Si deposition, allelic variants and expression of three Si transporter genes was studied in greater details. The high Si accumulating line PI548452 showed 12-fold increase in leaf Si content compared to low Si lines. Expression of HiSil2b and HiSil2c effluxer genes showed root and leaf specific expression, respectively, providing evidence for tissue specific Si transport and the basis for precise management of Si uptake to improve abiotic and biotic stresses. In summary, this study uncovered the novel accessions, haplotypes, allelic diversity, and the potential candidate genes underpinning the mineral nutrient accumulation in soybean.

Influence of the application of humic substances on the growth of watermelon and melon seedlings

Growing watermelon (Citrullus lanatus) and melon (Cucumis melo) is an important activity in the Brazilian Cerrado; however, many factors limit cultivation, including the difficulty of producing high-quality seedlings. In this study, the effect of humic substances (HS) on growth of ‘Crimson Sweet’ watermelon and ‘Yellow’ melon seedlings was evaluated. An experiment was carried out in a completely randomized design with five HS treatments applied to the soil: 0 (control), 5, 10, 15, and 20 g L-1. The growth of watermelon and melon seedlings was influenced by the application of humic substances. Use of HS increased plant height, stem diameter, root length, root volume, shoot dry biomass, root dry biomass, and Dickson’s quality index. HS boost plant growth, whose improved root system may have provided greater absorption and accumulation of mineral nutrients. Based on the quality of the seedlings (Dickson index), the application of 14 g L-1 of HS is recommended for watermelon seedling production and 15 g L-1 of HS for melon seedling production.

Effects of elevated ozone on physiology, growth, yield and grain quality of rice (Oryza sativa L.): An ozone gradient experiment

Rice (Oryza sativa L.) as the staple food is widely grown, but the current high tropospheric ozone (O3) pollution has seriously threatened the rice production. We performed an experiment on four rice cultivars widely grown in the Yangtze River Delta region of China, which were exposed to five O3 treatments under open top chambers. The effects of O3 on leaf physiology, growth, yield and grain quality of rice were comprehensively explored, and the results showed that (i) elevated O3 reduced the light-saturated rate of CO2 assimilation (Asat) and stomatal conductance (gs), and the O3-induced decrease in Asat was mainly attributed to stomatal limitation under low O3 treatment whereas stomatal and biochemical co-limitation under high O3 treatment; (ii) elevated O3 did not affected the harvest index since the inhibition of shoot biomass and yield was the same extent, which indicated that O3 does not alter the remobilization of carbon assimilates from vegetative organs to grains; (iii) only ambient air plus 60 ppb O3 treatment (NF60) significantly reduced the yield of rice, which was caused by the combined reduction of individual grain weight, grain number, and panicle number; (iv) elevated O3 did not significantly affect the concentration of mineral nutrients in grains, while the effect of O3 on the concentration of amino acids was consistent with biphasic O3-response profile. NF60 had a greater reduction in the concentration of essential amino acids than non-essential amino acids; (v) NF60 significantly reduced the accumulation of mineral nutrients and amino acid in grain due to a decrease in grain yield. These results are conducive to a comprehensive understanding of the impacts of O3 on rice, and also indicated that the risk assessment of O3 on crops would need to consider both crop yield and grain quality.

Seasonal changes of mineral nutrients absorption and allocation in fruit of Zanthoxylum bungeanum ‘Hanyuan’ during the development

Learn about the dynamic changes of mineral nutrients in fruit is important to make effective fertilization measures during the fruit development. The content and accumulation of mineral nutrients (included N, P, K, Ca, Mg, Fe, Mn, Cu and Zn) in fruit (included pericarp, seed and whole fruit) of Zanthoxylum bungeanum 'Hanyuan' were measured during the development to explore nutrient requirements and allocation. The changes of nutrient contents and accumulation in fruit of Z. bungeanum ‘Hanyuan’ showed a similar trend. A temporary increase was observed in the content of N, P, Mg, Mn and Cu after blooming (AF). Subsequently, all nutrient contents declined rapidly during the fruit enlargement stage and a slight decrease during the seed formation stage, while the nutrient contents remained relatively stable in the other stages. The nutrient accumulation increased the most rapidly during the fruit enlargement and seed development stages, and there was a highly significant linear correlation between the fruit nutrient accumulation and dry weight (P < 0.05). Except for N and Mn, the content and accumulation of other nutrients were higher in the seed than that in the pericarp. Furthermore, the nutrient accumulation in fruit at maturity (115 d AF) ranked as Ca > K > N > Mg > P > Fe > Mn > Zn > Cu. Both the fruit enlargement (15–39 d AF) and seed development (57–86 d AF) stages are crucial periods for nutrient requirements. The nutrient absorption by the seed was increased, and nutrient accumulation in the pericarp tended to slow down or remained relatively stable during the seed development stage.

Melatonin in business with abiotic stresses in vegetable crops

Vegetable crops are very important to the agriculture sector since they are the primary source of many of the vitamins and minerals that are required for a balanced diet. In contrast, vegetable production is frequently vulnerable to abiotic stresses such as heavy metals, salinity, cold, heat, and drought stress, which can have a negative impact on yield and quality. Recently, melatonin (MEL) has been identified as a universal plant growth regulator. MEL is a multifunctional, nontoxic, and universal bioactive molecule with low molecular weight. MEL regulate plant growth, protected photosynthetic system, delayed in leaf senescence, promoting root system architecture, maintain ion homeostasis, upregulated antioxidant enzyme pool, increased osmolytes accumulation, and balanced redox homeostasis. MEL also plays an important role in the alleviation of abiotic stress in vegetable crops. Furthermore, MEL restricted heavy metals accumulation and increased mineral nutrient accumulation in many vegetables crops. This study aims to provide a concise overview of the possible impact of MEL on enhancing the resilience of vegetable crop to abiotic stresses.

Influence of cutting time interval and season on productivity, nutrient partitioning, and forage quality of blue panicgrass (Panicum antidotale Retz.) under saline irrigation in Southern region of Morocco.

Salinity has become a major issue in various parts of the world negatively impacting agricultural activities and leading to diminished crop potential and lower yields. Such situation calls for urgent interventions such as adopting salt-tolerant crops to fill the gap in food and feed availability. Blue panicgrass (Panicum antidotale Retz.) is a promising salt-tolerant forage crop that has shown an appropriate adaptation and performance in the saline, arid, and desertic environments of southern Morocco. However, for obtaining a highest forage productivity with nutritional quality, optimization of the cutting interval is required. Thus, the objective of this study was to determine the optimal cutting time interval allowing high forage production and quality under high salinity conditions. This experiment was conducted over one entire year covering the summer and winter seasons. The effect of five cutting time intervals on selected agro-morphological traits, crop productivity, mineral nutrient accumulation, and forage quality of blue panicgrass in the region of Laayoune, southern Morocco. The finding of this study recommend that cutting blue panicgrass every 40 days maximized the annual fresh and dry forage yield as well as the protein yield, which reached 74, 22, and 2.9 t/ha, respectively. This study also revealed a significant effect of the season on both productivity and quality. However, forage yield declined during the winter and increased during the summer, while protein content increased during winter compared to summer. The mineral nutrient partitioning between shoots and roots, especially the K+/Na+ ratio, indicated that blue panicgrass has salt tolerance mechanism as it excluded sodium from the roots and compartmentalized it in the leaves. In conclusion, there is a potential of blue panicgrass on sustaining forage production under salt-affected drylands, as demonstrated by the response to two key questions: (a) a technical question to farmers for its adoption such as at which interval should blue panicgrass be harvested maximizing both forage yield and quality? And (b) a scientific question on how does blue panicgrass maintain high K+/Na+ ratio to cope with salinity stress?

Mineral Nutrient Uptake, Accumulation, and Distribution in Cunninghamia lanceolata in Response to Drought Stress.

Mineral accumulation in plants under drought stress is essential for drought tolerance. The distribution, survival, and growth of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), an evergreen conifer, can be affected by climate change, particularly seasonal precipitation and drought. Hence, we designed a drought pot experiment, using 1-year-old Chinese fir plantlets, to evaluate drought effects under simulated mild drought, moderate drought, and severe drought, which corresponds to 60%, 50%, and 40% of soil field maximum moisture capacity, respectively. A treatment of 80% of soil field maximum moisture capacity was used as control. Effects of drought stress on mineral uptake, accumulation, and distribution in Chinese fir organs were determined under different drought stress regimes for 0-45 days. Severe drought stress significantly increased phosphorous (P) and potassium (K) uptake at 15, 30 and 45 days, respectively, within fine (diameter < 2 mm), moderate (diameter 2-5 mm), and large (diameter 5-10 mm) roots. Drought stress decreased magnesium (Mg) and manganese (Mn) uptake by fine roots and increased iron (Fe) uptake in fine and moderate roots but decreased Fe uptake in large roots. Severe drought stress increased P, K, calcium (Ca), Fe, sodium (Na), and aluminum (Al) accumulation in leaves after 45 days and increased Mg and Mn accumulation after 15 days. In stems, severe drought stress increased P, K, Ca, Fe, and Al in the phloem, and P, K, Mg, Na, and Al in the xylem. In branches, P, K, Ca, Fe, and Al concentrations increased in the phloem, and P, Mg, and Mn concentrations increased in the xylem under severe drought stress. Taken together, plants develop strategies to alleviate the adverse effects of drought stress, such as promoting the accumulation of P and K in most organs, regulating minerals concentration in the phloem and xylem, to prevent the occurrence of xylem embolism. The important roles of minerals in response to drought stress should be further evaluated.

Melatonin-mediated endogenous nitric oxide coordinately boosts stability through proline and nitrogen metabolism, antioxidant capacity, and Na+/K+ transporters in tomato under NaCl stress.

The interactions between nitric oxide (NO) and melatonin in alleviating sodium chloride (NaCl) toxicity in plants are poorly comprehended. Here, the associations between the exogenous application of melatonin and endogenous NO levels in inducing tomato seedlings' defense response during NaCl toxicity were investigated. The results indicated that the application of melatonin (150 μM) increased height (23.7%) and biomass (32.2%), improved chlorophyll (a (137%) and b (92.8%)), and proline metabolisms, and reduced the contents of superoxide anion radicals (49.6%), hydrogen peroxide (31.4%), malondialdehyde (38%), and electrolyte leakage (32.6%) in 40-day-old tomato seedlings grown under NaCl (150 mM) treatment. Melatonin increased the antioxidant defense system in NaCl-stressed seedlings by increasing the activity of the antioxidant enzymes. Melatonin also improved N metabolism and endogenous NO content in NaCl-stressed seedlings by upregulating the activity of enzymes implicated in N assimilation. Furthermore, melatonin improved ionic balance and reduced Na content in NaCl-exposed seedlings by upregulating the expression of genes involved in K/Na ratio homeostasis (NHX1-4) and increasing the accumulation of mineral nutrients (P, N, Ca, and Mg). However, the addition of cPTIO (100 μM; an NO scavenger) reversed the beneficial impacts of melatonin, indicating the effective function of NO in melatonin-induced defense mechanisms in NaCl-stressed tomato seedlings. Therefore, our results revealed that melatonin improves the tolerance of tomato plants during NaCl toxicity by mediating internal NO.

Indigenous and commercial isolates of arbuscular mycorrhizal fungi display differential effects in Pyrus betulaefolia roots and elicit divergent transcriptomic and metabolomic responses.

Arbuscular mycorrhizal fungi (AMF) are beneficial soil fungi which can effectively help plants with acquisition of mineral nutrients and water and promote their growth and development. The effects of indigenous and commercial isolates of arbuscular mycorrhizal fungi on pear (Pyrus betulaefolia) trees, however, remains unclear. Trifolium repens was used to propagate indigenous AMF to simulate spore propagation in natural soils in three ways: 1. the collected soil was mixed with fine roots (R), 2. fine roots were removed from the collected soil (S), and 3. the collected soil was sterilized with 50 kGy 60Co γ-radiation (CK). To study the effects of indigenous AMF on root growth and metabolism of pear trees, CK (sterilized soil from CK in T. repens mixed with sterilized standard soil), indigenous AMF (R, soil from R in T. repens mixed with sterilized standard soil; S, soil from S in T. repens mixed with sterilized standard soil), and two commercial AMF isolates (Rhizophagus intraradices(Ri) and Funneliformis mosseae (Fm)) inoculated in the media with pear roots. Effects on plant growth, root morphology, mineral nutrient accumulation, metabolite composition and abundance, and gene expression were analyzed. AMF treatment significantly increased growth performance, and altered root morphology and mineral nutrient accumulation in this study, with the S treatment displaying overall better performance. In addition, indigenous AMF and commercial AMF isolates displayed common and divergent responses on metabolite and gene expression in pear roots. Compared with CK, most types of flavones, isoflavones, and carbohydrates decreased in the AMF treatment, whereas most types of fatty acids, amino acids, glycerolipids, and glycerophospholipids increased in response to the AMF treatments. Further, the relative abundance of amino acids, flavonoids and carbohydrates displayed different trends between indigenous and commercial AMF isolates. The Fm and S treatments altered gene expression in relation to root metabolism resulting in enriched fructose and mannose metabolism (ko00051), fatty acid biosynthesis (ko00061) and flavonoid biosynthesis (ko00941). This study demonstrates that indigenous AMF and commercial AMF isolates elicited different effects in pear plants through divergent responses from gene transcription to metabolite accumulation.

Mineral nutrient dynamics in pecans (Carya illinoensis) 'Mahan' grown in southern China.

It is of great significance to study the nutritional characteristics of plants. Further understanding of plant mineral nutrient dynamics can provide theoretical basis for scientific fertilization to improve fruit quality and yield. In this study, eight mineral elements (N, P, K, Ca, Mg, Mn, Zn, B) were measured at regular intervals in leaves and kernels of the pecan "Mahan" planted in southern China. The study discussed the characteristics of mineral nutrient dynamics of pecan through the indicators of concentration, accumulation and cumulative relative rate, a new first proposed indicator, and focused on critical time, intensity, amount of mineral nutrients required in pecan during the fruit developing period, as well as the transfer information of the elements in leaves and kernels. The results show that the mineral nutrient requirements of the leaves and kernels are not identical, with an upward trend in nutrient accumulation within the kernel. The most abundant mineral nutrients in the leaves and kernels were N, K and Ca with Ca being greater than N in leaves. In particular, the concentration of Mn in pecan 'Mahan' is higher than that of other plants, and its Mg content is also higher than that of P in kernels. The dynamic changes of mineral nutrients in walnut showed obvious stages, with a trend of "slow (before mid-July) - fast (mid-July to late August) - slow (late August to late September) - fast (late September to harvest)". The "critical period" of kernels was before mid-July, during which the cumulative relative rates increased rapidly, indicating that the kernels had a great potential to absorb mineral nutrients. Significant accumulation of mineral nutrients occurred from mid-July to late August and late September to the end.

Red to Blue Light Ratio and Iron Nutrition Influence Growth, Metabolic Response, and Mineral Nutrients of Spinach Grown Indoors

Leafy greens are increasingly being produced indoors with electric lighting from light-emitting diodes (LEDs). Red (R) and blue (B) LEDs are commonly used to ensure healthy plant growth, but biofortification techniques can potentially maximise nutritional quality. The aim of the study was to evaluate the effects of B (peak = 450 nm) and R (peak = 665 nm) light ratios (R:B) of 9:1, 3:1, and 1:3 on growth, metabolic response, and the accumulation of mineral nutrients in spinach ‘Corvair F1’ and ‘Space F1’ grown in hydroponic solutions with different iron (Fe) concentrations (2, 5, and 15 mg L−1). Plant biomass and leaf length, width, and number generally decreased as the R:B decreased, leading to a high concentration of Fe in the solution. A higher Fe dose increased the contents of some other minerals but depended on the R:B and cultivar. For example, Zn generally increased with increasing Fe but Cu content decreased, especially in ‘Space F1’. There were less-profound effects of the R:B and Fe dose on metabolites or antioxidant capacity. The research findings suggest that the overall nutritional quality of spinach could improve with lighting and Fe biofortification strategies and thus increase the sustainability of indoor crop production.

Dual-function DEFENSIN 8 mediates phloem cadmium unloading and accumulation in rice grains.

Grain cadmium (Cd) is translocated from source to sink tissues exclusively via phloem, though the phloem Cd unloading transporter has not been identified yet. Here, we isolated and functionally characterized a defensin-like gene DEFENSIN 8 (DEF8) highly expressed in rice (Oryza sativa) grains and induced by Cd exposure in seedling roots. Histochemical analysis and subcellular localization detected DEF8 expression preferentially in pericycle cells and phloem of seedling roots, as well as in phloem of grain vasculatures. Further analysis demonstrated that DEF8 is secreted into extracellular spaces possibly by vesicle trafficking. DEF8 bound to Cd in vitro, and Cd efflux from protoplasts as well as loading into xylem vessels decreased in the def8 mutant seedlings compared with the wild type. At maturity, significantly less Cd accumulation was observed in the mutant grains. These results suggest that DEF8 is a dual function protein that facilitates Cd loading into xylem and unloading from phloem, thus mediating Cd translocation from roots to shoots and further allocation to grains, representing a phloem Cd unloading regulator. Moreover, essential mineral nutrient accumulation as well as important agronomic traits were not affected in the def8 mutants, suggesting DEF8 is an ideal target for breeding low grain Cd rice.

Critical dilution curves for calcium, magnesium, and sulfur in potato (Solanum tuberosum L. Group Andigenum) cultivars Diacol Capiro and Pastusa Suprema

Diagnostic tools must be developed to optimize the management of calcium (Ca), magnesium (Mg), and sulfur (S) in potato crops. This research aimed to develop the critical dilution curves for Ca, Mg, and S in potato (Solanum tuberosum L. Group Andigenum), establishing harvest indices and characterizing the nutrient relationships. Four field experiments were established in two growth cycles in the localities of Facatativá (high fertility soils) and Chocontá (low fertility soils) in Colombia. Two cultivars (Diacol Capiro and Pastusa Suprema) and two levels of fertilization (0 and 100% of macro and micronutrients) were evaluated. The dry biomass and Ca, Mg, and S concentration in tubers and aerial parts were measured from the formation of main stems until tuber maturation; this information was used to calculate the critical concentrations (Cac, Mgc, Sc), harvest indices, and nutrient correlations. The critical curves established were for Capiro: Cac = 1.7326W-0.2956, Mgc = 0.7191W-0.2803, Sc = 0.6461W-0.3904 and for Suprema: Cac = 1.523W-0.2559, Mgc = 0.6507W-0.236, Sc = 0.7669W-0.3932. Critical levels were established for five phenological stages. Capiro had a higher accumulation of Ca, Mg, and S in the tubers independently of locality, while Suprema had better performance in Chocontá. The accumulation of mineral nutrients in the tubers followed the order Ca&lt;Mg&lt;S. Capiro was a genotype with greater Ca-Mg-S uptake and better adaptation to locations. The Cac, Mgc and Sc curves provided a tool to carry out the nutritional diagnoses at critical stages of development and they are the first ones reported for potato of Group Andigenum.

Gypsum endemics accumulate excess nutrients in leaves as a potential constitutive strategy to grow in grazed extreme soils.

Extreme soils often have mineral nutrient imbalances compared to plant nutritional requirements and co‐occur in open areas where grazers thrive. Thus, plants must respond to both constraints, which can affect nutrient concentrations in all plant organs. Gypsum soil provides an excellent model system to study adaptations to extreme soils under current grazing practices as it harbours two groups of plant species that differ in their tolerance to gypsum soils and foliar composition. However, nutrient concentrations in organs other than leaves, and their individual responses to simulated herbivory, are still unknown in gypsum plants. We studied plant biomass, root mass ratio and nutrient partitioning among different organs (leaves, stems, coarse roots, fine roots) in five gypsum endemics and five generalists cultivated in gypsum and calcareous soils and subjected to different levels of simulated browsing. Gypsum endemics tended to have higher elemental concentration in leaves, stems and coarse roots than generalist species in both soil types, whereas both groups tended to show similar high concentrations in fine roots. This behaviour was especially clear with sulphur (S), which is found in excess in gypsum soils, and which endemics accumulated in leaves as sulphate (>50% of S). Moreover, plants subjected to clipping, regardless of their affinity to gypsum, were unable to compensate for biomass losses and showed similar elemental composition to unclipped plants. The accumulation of excess mineral nutrients by endemic species in aboveground organs may be a constitutive nutritional strategy in extreme soils and is potentially playing an anti‐herbivore role in grazed gypsum outcrops.

Beneficial role of methyl jasmonate on morphological, physiological and phytochemical responses of Calendula officinalis L. under Chromium toxicity.

Contamination of soil with chromium (Cr) is a rising problem in terms of agricultural sustainability and food safety. Here, the effects of methyl jasmonate (MJ; 0, 5, and 10 µM) on alleviating Cr stress (0, 100, and 200 µM) were surveyed in pot marigold (Calendula officinalis L.). The results showed that Cr stress significantly reduced photosynthetic pigments and leaf accumulation of total soluble sugars, total starch, and mineral nutrients and, consequently, lowered the height and biomass of pot marigold plants. Chromium toxicity also increased the leaf levels of oxidative stress markers and induced oxidative stress, which was associated with damage to bio-membranes and increased levels of malondialdehyde. However, MJ supplementation reduced the leaf accumulation of Cr, increased the content of photosynthetic pigments, and improved the performance of the photosynthetic machinery in Cr-stressed plants. MJ supplementation boosted the antioxidant defense system by upregulating antioxidant enzymes, glyoxalase enzymes, and the ascorbate-glutathione (AsA-GSH) pool redox, which significantly diminished Cr-induced oxidative stress. Hence, MJ supplementation might be a practicable approach for reducing Cr absorption and its negative impacts on pot marigold plants growing under Cr-contaminated conditions. Clinical trials registration Not applicable.

Biomass and mineral nutrient partitioning among self-pollinated and cross-pollinated fruit on the same strawberry plant.

Pollen-parent effects on fruit size and quality have been found previously among competing self-pollinated and cross-pollinated fruit on the same Redlands Joy strawberry plant. These effects occur independently of the percentage of fertilized seeds on the fruit, but the expression of these effects on fruit size and some aspects of quality are greatest when calcium is in shortest supply. Here, we aimed to clarify at what developmental stages the self-pollinated and cross-pollinated fruit diverge in size and quality and whether differences between self-pollinated and cross-pollinated fruit are due to early differences in nutrient accumulation. Fruit were harvested at 1, 2 and 3 weeks after hand-pollination and at full ripeness, approximately 4 weeks after hand-pollination. We measured fruit mass, length, diameter, colour, and the concentrations of aluminium, boron, calcium, copper, iron, nitrogen, magnesium, manganese, sodium, phospho-rous, potassium and zinc. Temporary increases in fruit mass, length or diameter due to cross-pollination were evident at 1 or 2 weeks after pollination. Consistent increases in size and skin darkness from cross-pollination emerged in the final week of fruit development. We found little evidence that self-pollinated and cross-pollinated fruit differed in mineral nutrient accumulation at any stage of fruit development. The results demonstrate that cross-pollination effects on strawberry fruit size are evident briefly during early fruit growth but emerge mainly during the final week of fruit development. The effects of cross-pollination on fruit size are not the result of early differences in mineral nutrient accumulation between self-pollinated and cross-pollinated fruit.

Investigation of Mineral Nutrient and Heavy Metal Accumulation Status of Senecio Vernalis Waldst. & Kit. Collected from Different Habitats of Aksaray/Turkey

ABSTRACT In this study, Senecio vernalis Waldst. & Kit. was analyzed to determine a phytoremediation potential and nutritional contents are estimated. The plant and soil samples were collected between Karaören and Karkın villages in Aksaray in May (2021). The mineral contents (Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Ni, P, S, Zn) of the collected plant and soil samples were determined by ICP-MS and the obtained data were analyzed statistically. In soil, Ca, Fe, K and Zn values were in the optimal value whereas Al, Cu, Mg, Mn and Ni values were above the optimal values. This means that there is bioaccumulation of these heavy metals (Al, Cu, Mg, Mn and Ni) in the soil. Likewise, the concentrations of Ca, Cu, K, Mn and Zn in the plant were among the optimum values, while Al, Fe, Mg, and Ni ratios were higher than the quantification limit. The rate of these metals in the roots and other shoots of the plant are higher than in the soil. Our results showed that Senecio vernalis is a very good accumulator of Fe, Mg and Ni, and also the phytoextraction and phytoremediation ability of the plant is high.

Phase-Selective Synthesis of Anatase and Rutile TiO2 Nanocrystals and Their Impacts on Grapevine Leaves: Accumulation of Mineral Nutrients and Triggering the Plant Defense.

Titanium dioxide nanocrystals (TiO2 NCs), through their photocatalytic activity, are able to generate charge carriers and induce the formation of various reactive oxygen species (ROS) in the presence of O2 and H2O. This special feature makes TiO2 an important and promising material in several industrial applications. Under appropriate antioxidant balancing, the presence of ROS is crucial in plant growth and development, therefore, the regulated ROS production through the photocatalytic activity of TiO2 NCs may be also exploited in the agricultural sector. However, the effects of TiO2 NCs on plants are not fully understood and/or phase-pure TiO2 NCs are rarely used in plant experiments. In this work, we present a phase-selective synthesis of TiO2 NCs with anatase and rutile crystal phases. The nanomaterials obtained were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), diffuse reflectance UV-Vis spectroscopy, and electron paramagnetic resonance spectroscopy (EPR). In field experiments, Vitis vinifera cv. Cabernet Sauvignon leaves developed under natural sunlight were treated with aqueous dispersions of TiO2 NCs at concentrations of 0.001, 0.01, 0.1, and 1 w/v%. The effect of the applied nanocrystals was characterized via leaf photochemistry, mineral nutrient contents, and pyridoxine levels. We found that stress responses of grapevine to anatase and rutile NCs treatments are different, which can be related to the different ROS profiles of the two polymorphs. Our results indicate that TiO2 NCs may be utilized not only for direct pathogen inactivation but also for eliciting plant defense mechanisms.