Micronutrient Accumulation Research Articles

Growth, Nutrient Accumulation, and Drought Tolerance in Crop Plants with Silicon Application: A Review

Plants take up silicon (Si) from the soil which impacts their growth and nutrient accumulation. It increases plant resistance to abiotic and biotic stresses such as drought, salinity, and heavy metal, diseases, and pest infestation. However, until recently, research of Si application on the crop is limited. This article reviews the recent progress of research on Si application on crop growth and yield, nutrient availability in soil and accumulation, and drought tolerance of crop plants. The review’s findings show that Si improves crop development and output under stressful environmental conditions. Silicon increases the availability and accumulation of both macronutrients (nitrogen, potassium, calcium, and sulphur) and micronutrients (iron and manganese). It improves drought resistance by increasing plant water usage efficiency and reducing water loss during transportation. Silicon application is a crucial aspect of crop productivity because of all of these favorable attributes. The gaps in current understandings are identified. Based on the outcome of the present research, future scopes of research on this field are proposed.

Enhancing Agrichemical Delivery and Plant Development with Biopolymer-Based Stimuli Responsive Core-Shell Nanostructures.

The inefficient delivery of agrichemicals in agrifood systems is among the leading cause of serious negative planetary and public health impacts. Such inefficiency is mainly attributed to the inability to deliver the agrichemicals at the right place (target), right time, and right dose. In this study, scalable, biodegradable, sustainable, biopolymer-based multistimuli responsive core-shell nanostructures were developed for smart agrichemical delivery. Three types of responsive core/shell nanostructures incorporated with model agrichemicals (i.e., CuSO4 and NPK fertilizer) were synthesized by coaxial electrospray, and the resulting nanostructures showed spherical morphology with an average diameter about 160 nm. Tunable agrichemical release kinetics were achieved by controlling the surface hydrophobicity of nanostructures. The pH and enzyme responsiveness was also demonstrated by the model analyte release kinetics (up to 7 days) in aqueous solution. Finally, the efficacy of the stimuli responsive nanostructures was evaluated in soil-based greenhouse studies using soybean and wheat in terms of photosynthesis efficacy and linear electron flow (LEF), two important metrics for seedling development and health. Findings confirmed plant specificity; for soybean, the nanostructures resulted in 34.3% higher value of relative chlorophyll content and 41.2% higher value of PS1 centers in photosystem I than the ionic control with equivalent agrichemical concentration. For wheat, the nanostructures resulted in 37.6% higher value of LEF than the ionic agrichemicals applied at 4 times higher concentration, indicating that the responsive core-shell nanostructure is an effective platform to achieve precision agrichemical delivery while minimizing inputs. Moreover, the Zn and Na content in the leaves of 4-week-old soybean seedlings were significantly increased with nanostructure amendment, indicating that the developed nanostructures can potentially be used to modulate the accumulation of other important micronutrients through a potential biofortification strategy.

Plant species and pH dependent responses to copper toxicity

High copper (Cu) levels in soil caused by anthropic activity, as in vineyards, can cause phytotoxicity and reduce plant productivity. However, the distribution of Cu chemical-species in the soil and then, the level of its availability for crops can be considerably altered by pH and root exudates in the rhizosphere. The study aimed at investigating the influence of both pH and excessive Cu concentrations on physiological and morphological responses of two different plant species, cucumber (Cucumis sativus L.) and oat (Avena sativa L.). The experiment was conducted with two plant species, cucumber (Cucumis sativus L.) and oat (Avena sativa L.), three pH levels (4.5, 6.0 and 7.5) and three Cu concentrations (0.2, 5 and 50 µM). Both plant species showed the capacity to change the pH of the solution, but oat plants showed higher capacity to alkalize the nutrient solution than cucumber plants to reduce Cu availability. Excluding a few exceptions, exudation increased with increasing Cu supply in both plant species studied. Exudation resulted also pH dependent, particularly visible for flavonoids in cucumber plants. Overall, flavonoid release resulted higher in cucumber than in oat while the release of phenolics was higher in oat compared to cucumber. Cucumber and oat plants supplied with 50 µM Cu and pH 4.5 exhibited the lowest growth and development because of higher Cu availability. On the other hand, nutrient solution at pH 7.5 and high Cu concentration stimulated root development especially in cucumber plants. Copper interfered with the accumulation of both macro and micronutrients, yet the synergisms and/or antagonisms were species and pH dependent. Both plants presented the highest Cu concentration in shoots and roots at 50 µM Cu in all the pH values solution, especially in the roots. Oat plants showed more resistance to high Cu concentrations in solution over a wide range of pH exhibiting a better plant development and more Cu-induced synergistic responses to nutrients than cucumber. Oat plants can be used in Cu-contaminated soils as phytostabilizer plants.

Genetic analysis toward more nutritious barley grains for a food secure world

BackgroundUnderstanding the relationships between nutrition, human health and plant food source is among the highest priorities for public health. Therefore, enhancing the minerals content such as iron (Fe), zinc (Zn) and selenium (Se) in barley (Hordeum vulgare L.) grains is an urgent need to improve the nutritive value of barley grains in overcoming malnutrition and its potential consequencing. This study aimed to expedite biofortification of barley grains by elucidating the genetic basis of Zn, Fe, and Se accumulation in the grains, which will contribute to improved barley nutritional quality.ResultsA genome-wide association study (GWAS) was conducted to detect the genetic architecture for grain Zn, Fe, and Se accumulations in 216 spring barley accessions across two years. All the accessions were genotyped by single nucleotide polymorphisms (SNPs) molecular markers. Mineral heritability values ranging from moderate to high were revealed in both environments. Remarkably, there was a high natural phenotypic variation for all micronutrient accumulation in the used population. High-LD SNP markers (222 SNPs) were detected to be associated with all micronutrients in barley grains across the two environments plus BLUEs. Three genomic regions were detected based on LD, which were identified for the most effective markers that had associations with more than one trait. The strongest SNP-trait associations were found to be physically located within genes that may be involved in grain Zn and Fe homeostasis. Two putative candidate genes were annotated as Basic helix loop helix (BHLH) family transcription factor and Squamosa promoter binding-like protein, respectively, and have been suggested as candidates for increased grain Zn, Fe, and Se accumulation.ConclusionsThese findings shed a light on the genetic basis of Zn, Fe, and Se accumulation in barley grains and have the potential to assist plant breeders in selecting accessions with high micronutrient concentrations to enhance grain quality and, ultimately human health.

Biomass production and nutrient accumulation in physalis in two edaphoclimatic conditions

In Brazil, although there is a growing demand for physalis in the food industries, information on the nutritional management of the crop is still incipient. This study aimed to evaluate the biomass production and accumulation of nutrients in the shoots and fruit of physalis in two cultivation sites. Two field experiments were conducted, one where the soil was Typic Quartzipsamment in the municipality of Diamantina and the other where the soil was Rhodic Hapludox in the municipality of São João Evangelista, Minas Gerais State, Brazil. The experiments were conducted in a randomized complete block design with four replicates. The treatments were the evaluation period. Samples were collected every 15 days the day of planting of the seedlings in the field for a period of 240 days. Dry matter and nutrient accumulation in shoot and fruit were evaluated. The biomass production and nutrient accumulation were higher in the edaphoclimatic conditions at São João Evangelista compared to the conditions at Diamantina. Macronutrient accumulation was in the following order: N > K > Ca > S > Mg > P in shoot and N > K > P > S > Ca > Mg in fruit. Micronutrient accumulation in shoot and fruit was in the following order: Fe > Mn > Zn > B > Cu.

Growth, nutrient accumulation and yield of onion as a function of micronutrient fertilization

ABSTRACT Micronutrients structurally constitute several enzymes and act as a cofactor of essential proteins to maintain cell function, thereby contributing to crop growth and yield. The objective of this study was to evaluate the leaf content, growth, accumulation of micronutrients, classification and yield of onion as a function of fertilization with boron, cooper and zinc in two years of cultivation. The experiments were carried out from June to November in 2018 and 2019, in a soil classified as Ultisol, both at the Rafael Fernandes Experimental Farm, belonging to the Universidade Federal Rural do Semiárido, in the municipality of Mossoró, Rio Grande do Norte, Brazil. The experimental design was in randomized blocks with 15 treatments and four replicates. The treatments consisted of application of doses of B, Cu and Zn, in two experiments. Contents of B, Cu and Zn in the diagnostic leaf, growth, accumulation of B, Cu and Zn in the leaf, bulb and total, classification and commercial, non-commercial and total yields were evaluated. Application of B, Cu and Zn did not influence the number of leaves, relation of bulb shape, leaf, bulb, and total dry mass and yield of onion. Application of B, Cu and Zn, respectively at doses of 1-2-1 kg ha-1 favored a greater accumulation of B, Zn and Cu in the bulb. Higher number of leaves, leaf dry mass, bulb dry mass, total dry mass, class 1 bulbs and non-commercial yield were produced in Experiment 1.

Growth and Nutritional Quality of Lemnaceae Viewed Comparatively in an Ecological and Evolutionary Context.

This review focuses on recently characterized traits of the aquatic floating plant Lemna with an emphasis on its capacity to combine rapid growth with the accumulation of high levels of the essential human micronutrient zeaxanthin due to an unusual pigment composition not seen in other fast-growing plants. In addition, Lemna’s response to elevated CO2 was evaluated in the context of the source–sink balance between plant sugar production and consumption. These and other traits of Lemnaceae are compared with those of other floating aquatic plants as well as terrestrial plants adapted to different environments. It was concluded that the unique features of aquatic plants reflect adaptations to the freshwater environment, including rapid growth, high productivity, and exceptionally strong accumulation of high-quality vegetative storage protein and human antioxidant micronutrients. It was further concluded that the insensitivity of growth rate to environmental conditions and plant source–sink imbalance may allow duckweeds to take advantage of elevated atmospheric CO2 levels via particularly strong stimulation of biomass production and only minor declines in the growth of new tissue. It is proposed that declines in nutritional quality under elevated CO2 (due to regulatory adjustments in photosynthetic metabolism) may be mitigated by plant–microbe interaction, for which duckweeds have a high propensity.

Effects of urban wastewater application on growth, biomass, nutrition, and heavy-metal accumulation of Populus nigra L. “62/154,” P. alba L. “20/45,” P. euramericana (Dode) Guinier “92/40,” and Salix excelsa S.G. Gmel grown in heavy-metal contaminated soil

Iran is located in a dry climate zone, and climate change has substantially reduced its precipitation and water resources. Reusing wastewaters from urban communities can meet some requirements for irrigation and fertilization of tree plantations in arid environments, leading to sustainable wastewater recycling, enhanced biomass production, and reduced land degradation. The objective of this study was to test the growth, biomass, nutrition, and heavy-metal accumulation of poplars [Populus nigra L. “62/154,” P. alba L. “20/45,” P. euramericana (Dode) Guinier “92/40”], and willow (Salix excelsa S.G. Gmel) in a pot experiment at four and eight months after planting when grown in soils irrigated with tap water (SITW) and wastewater (SIWW). After four months, SIWW treatment had no significant effect on growth, biomass, nor absorption of macronutrients. After eight months, SIWW treatment of poplars and willow significantly (p = 0.000) increased: (1) height, (2) leaf area, (3) root, stem, leaf, and total biomass, and (5) phytoextraction and phytoaccumulation of macro-/micro-nutrients and heavy metals in tree tissues, over trees receiving the SITW treatment. There were significant differences in growth, biomass, and accumulation of micronutrients and heavy metals in poplar versus willow tissues, with the highest biomass production and tissue-specific content of heavy metals in P. nigra trees, and the greatest total concentrations of heavy metals in P. alba and S. excelsa trees. In contrast, uptake of Fe, Cu, Ni, Cr and Pb were similar between poplar and willow, and phytoaccumulation of these elements was primarily in the roots. Leaf concentrations were highest for Zn and Mn. While P. nigra outperformed all other species overall, tolerance index (TI; defined as the tolerance to the heavy metals as calculated by the ratio of the biomass of SIWW trees relative to SITW trees) values exceeding 100% for all one-year-old poplar and willow trees demonstrated that they can be considered for planting in soil affected by urban wastewaters with similar contaminant profiles as in the current study.

Impact of Sewage Water on Vegetable Crops and Soils of Bihar

The study of present investigations revealed there is an accumulation of micronutrients and heavy metals in soils with maximum accumulation at the point of discharge. Continuous disposal of sewage-sludge, containing domestic and industrial effluents on agricultural land is a major source of plant nutrients, but it also contains a sufficient amount of non-essential and heavy metals causing soil pollution. Transfer of metals from added sewage sludge to the soils and subsequently uptake by the plants that enter the feed and food-chain which pose hazardous for human health and animals. Moreover, it is pointed out that continued monitoring or treatment of sewage water before disposal into the land or integrated water management are some of the suitable measures for effective utilization of poor quality water in sustainable agricultural production. The concentration of heavy metals like Ni, Cr, Cd and Pb in sewage sludge treated soils at nearby and distant sites from discharge point at Patna bye-pass were investigated. The study revealed that the sites nearest to discharge point contained appreciably higher concentration of these metal cations in comparison to the sites away from the discharge point of the sewage water. Plants growing on such soils accumulate excesses amount of micronutrients and heavy metals in their tissues which may enter in the system of animal and human being. Accumulation of trace metal cations in different plant species differed widely which varied from crop to crop and place to place. The relative accumulation of these metals in different plant species was noticed that leafy vegetables, viz. poi and red spinach (Amaranthus) accumulated most of trace metal cations to the greater extent in comparison to other crops. However, toxic concentration of these trace metal cations in plants and soils should be the matter of concern and indicate the need for continuous monitoring or treatment of sewage water before it is laid down into the field. Though the study during the investigations confirm that sewage water (domestic & urban origin) can certainly and effectively increase water resource for irrigation but there is need for regular monitoring of the concentrations of trace metal cations and potentially toxic elements in soils as well as in plants.

Comparison of two controlled-release fertilizer formulations for cut-and-come-again harvest yield and mineral content of Lactuca sativa L. cv. Outredgeous grown under International Space Station environmental conditions

Red Romaine leaf lettuce (Lactuca sativa L. cv. Outredgeous) was grown in ground-based analogues of the Veggie plant-growth units used to grow salad vegetables for astronauts on the International Space Station (ISS). Plants were grown for 56 days with three “cut-and-come again” leaf harvests from the same plants. Six Biomass-Production-Systems-for-Education (BPSe) units were used to grow ‘Outredgeous’ (‘OR’) lettuce in a walk-in growth chamber under temperature, humidity, and LED-lighting conditions similar to those occurring in Veggie on ISS. Because of the ISS micro-gravity environment, both Veggie and ground-based BPSe units utilize one-way capillary wicking of water into an arcillite clay root substrate. In the present study, two different controlled-release fertilizer (CRF) formulations incorporated into the arcillite were compared for effects on ‘OR’ growth rate, overall yield, and mineral content of leaves harvested from the same plants 28, 48, and 56 days after planting. Both CRF treatments had a rapid-releasing T70 component that kept growth rate equivalent over the first two harvests. Growth rate for both CRF treatments increased from the first to the second harvest, but then declined from the second to the third harvest, more so for the slower-releasing T180 CRF than for the moderately-releasing T100 CRF. Tissue content of the macro-nutrients N, P, and K declined at each harvest for both CRFs, while content of the micro-nutrients B, Zn, and Mn increased. Although pH did not go out of the nominal range for availability of mineral nutrients to roots over the cropping cycle, and electrical-conductivity of rootzone salts was neither excessive nor depleted, tissue macronutrient depletion and micro-nutrient accumulation may have contributed to yield declines. Although either CRF formulation can support adequate yield of ‘OR’ lettuce over a 56-day period, the moderately-releasing T100 formulation tends to give slightly higher yield, especially during the last growth increment, and with non-deficient mineral content.

Influence of Drought and Salt Stress on Durum Wheat Grain Quality and Composition: A Review.

Durum wheat is a staple crop for the Mediterranean diet because of its adaptability to environmental pressure and for its large use in cereal-based food products, such as pasta and bread, as a source of calories and proteins. Durum wheat whole grains are also highly valued for their peculiar amount of dietary fiber and minerals, as well as bioactive compounds of particular interest for their putative health-beneficial properties, including polyphenols, carotenoids, tocopherols, tocotrienols, and phytosterols. In Mediterranean environments, durum wheat is mostly grown under rainfed conditions, where the crop often experiences environmental stresses, especially water deficit and soil salinity that may induce a hyperosmotic stress. In particular, changes in C and N accumulation due to these abiotic conditions, during grain filling, can influence starch and storage protein amount and composition in durum wheat caryopsis, thus influencing yield and quality traits. Recent advancements regarding the influence of water deficit and salinity stress on durum wheat are critically discussed. In particular, a focus on stress-induced changes in (a) grain protein content and composition in relation to technological and health quality; (b) starch and dietary fiber accumulation and composition; (c) phytochemical composition; (d) health-related grain micronutrient accumulation, such as Fe and Zn.

The potential use of Chlamydomonas reinhardtii and Chlorella sorokiniana as biostimulants on maize plants

Nitrogen deficiency and drought stress are among the major stresses faced by plants with negative consequence on crop production. The use of plant biostimulants is a very promising application in agriculture to improve crop yield, but especially to prevent the effect of abiotic stresses. Algae-derived biostimulants represent an efficient tool to stimulate the root development: while macroalgae have already been widely adopted as a source of biostimulants to improve plants growth and resilience, far less information is available for microalgae. The objective of this work is to investigate the stimulant ability on maize roots of two green algae species, Chlamydomonas reinhardtii and Chlorella sorokiniana, being respectively the model organism for Chlorophyta and one of the most promising species for microalgae cultivation at industrial scale. The results obtained demonstrate that both C. reinhardtii and C. sorokiniana cells promoted the development of maize root system compared to the untreated negative control. C. sorokiniana specifically increased the number of secondary roots, while improved micro-nutrients accumulation on roots and shoots was measured in the case of C. reinhardtii treated plants. When these microalgae-derived biostimulants were applied on plants grown in stress conditions as nitrogen deficiency, improved development of the root system was measured in the case of plants treated with C. sorokiniana biomass. Microalgae cultivation for biostimulant production can thus be considered as a bio-based process providing solutions for improving plant resilience toward stress conditions.

Deciphering role of technical bioprocess parameters for bioethanol production using microalgae.

Microalgae biomass is considered an important feedstock for biofuels and other bioactive compounds due to its faster growth rate, high biomass production and high biomolecules accumulation over first and second-generation feedstock. This research aimed to maximize the specific growth rate of fresh water green microalgae Closteriopsis acicularis, a member of family Chlorellaceae under the effect of pH and phosphate concentration to attain enhanced biomass productivity. This study investigates the individual and cumulative effect of phosphate concentration and pH on specific growth characteristics of Closteriopsis acicularis in autotrophic mode of cultivation for bioethanol production. Central-Composite Design (CCD) strategy and Response Surface Methodology (RSM) was used for the optimization of microalga growth and ethanol production under laboratory conditions. The results showed that high specific growth rate and biomass productivity of 0.342 day−1 and 0.497 g L−1 day−1 respectively, were achieved at high concentration of phosphate (0.115 g L−1) and pH (9) at 21st day of cultivation. The elemental composition of optimized biomass has shown enhanced elemental accumulation of certain macro (C, O, P) and micronutrients (Na, Mg, Al, K, Ca and Fe) except for nitrogen and sulfur. The Fourier transform infrared spectroscopic analysis has revealed spectral peaks and high absorbance in spectral range of carbohydrates, lipids and proteins, in optimized biomass. The carbohydrates content of optimized biomass was observed as 58%, with 29.3 g L−1 of fermentable sugars after acid catalyzed saccharification. The bioethanol yield was estimated as 51 % g ethanol/g glucose with maximum of 14.9 g/L of bioethanol production. In conclusion, it can be inferred that high specific growth rate and biomass productivity can be achieved by varying levels of phosphate concentration and pH during cultivation of Closteriopsis acicularis for improved yield of microbial growth, biomass and bioethanol production.

Transcriptional regulation of ZIP genes is independent of local zinc status in Brachypodium shoots upon zinc deficiency and resupply.

The biological processes underlying zinc homeostasis are targets for genetic improvement of crops to counter human malnutrition. Detailed phenotyping, ionomic, RNA-Seq analyses and flux measurements with 67 Zn isotope revealed whole-plant molecular events underlying zinc homeostasis upon varying zinc supply and during zinc resupply to starved Brachypodium distachyon (Brachypodium) plants. Although both zinc deficiency and excess hindered Brachypodium growth, accumulation of biomass and micronutrients into roots and shoots differed depending on zinc supply. The zinc resupply dynamics involved 1,893 zinc-responsive genes. Multiple zinc-regulated transporter and iron-regulated transporter (IRT)-like protein (ZIP) transporter genes and dozens of other genes were rapidly and transiently down-regulated in early stages of zinc resupply, suggesting a transient zinc shock, sensed locally in roots. Notably, genes with identical regulation were observed in shoots without zinc accumulation, pointing to root-to-shoot signals mediating whole-plant responses to zinc resupply. Molecular events uncovered in the grass model Brachypodium are useful for the improvement of staple monocots.

A path toward concurrent biofortification and cadmium mitigation in plant-based foods.

Millions of people are anemic due to inadequate consumption of foods rich in iron and zinc. Plant-based foods provide most of our dietary nutrients but may also contain the toxic heavy metal cadmium (Cd). A low level of Cd silently enters the body through the diet. Once ingested, Cd may remain for decades. Hence, prolonged intake of Cd-containing foods endangers human health. Research that leads towards micronutrient enrichment and mitigation of Cd in foods has therefore dual significance for human health. The breeding of Cd-tolerant cultivars may enable them to grow on Cd-polluted soils; however, they may not yield Cd-free foods. Conversely, sequestration of Cd in roots can prevent its accumulation in grains, but this mechanism also retains nutrients, hence counteracting biofortification efforts. A specific restriction of the Cd absorption capacity of crops would prevent Cd entry into the plant system while maintaining micronutrient accumulation and may thus be a solution to the dilemma. After recapitulating existing strategies employed for the development of Cd-tolerant and biofortified cultivars, this Viewpoint elaborates alternative approaches based on directed evolution and genome editing strategies for excluding Cd while enriching micronutrients in plant foods, which will concurrently help to eradicate malnutrition and prevent Cd intoxication.

Ash content in fruit samples of the <i>Actinidia kolomikta</i> genetic collection

Among the representatives of the Actinidia Lindl. genus, Actinidia kolomikta (Siebold et Zucc.) Planch. is valued as the most winter-hardy variety with high taste and dietary properties. The Federal Horticultural Research Centre for Breeding, Agrotechnology and Nursery has a live collection of Actinidia, which includes more than a hundred cultivated forms and varieties. In this study, ash content in Actinidia kolomikta fruits of 10 varieties and collection samples was studied by energy-dispersive X-ray spectroscopy using an analytical scanning electron microscope JEOL JSM6090 LA. A decreasing series was established for the accumulation of ash elements in the fruits of the studied samples: Ca> K> P> Mg> Mo> S> Se> Zn> Fe> Co> Si> Na. In terms of accumulation of useful macro- and micronutrients, the most valuable varieties were identified. The total accumulation of macronutrients in the fruit ash ranged from 28.6 to 45.3 wt%. This indicator was the highest in the fruits of Dolgovechnaya, Uslada and Vinogradnaya (42.068–45.638 wt%). The fruits of the Uslada variety were distinguished by a high content of phosphorus (5.89), silicon (0.504), sulfur (1.34) and potassium (23.596 wt%). In terms of micronutrient accumulation, the Pamyati Kolbasinoj variety (4.904 wt%) showed the highest levels of molybdenum (3.804) and selenium (0.801 wt%). Iron accumulated more readily in the fruits of the Uslada variety (0.161), cobalt — in Nadezhda (0.157), zinc — in Vinogradnaya (0.247) and Chempion (0.195). A statistically significant positive correlation (r > 0.7) was revealed in the accumulation of the following pairs of ash elements: sodium — sulfur (r = 0.70), phosphorus — potassium (r = 0.75), silicon — iron (r = 0.76), as well as molybdenum with phosphorus (r = 0.84), sulfur (r = 0.83) and potassium (r = 0.71). A statistically significant negative correlation was observed only for the accumulation of phosphorus and calcium (r = -0.71). According to the results, the fruits of the Actinidia kolomikta varieties under study can be an additional or alternative source of dietary minerals in functional food products.

Raman Molecular Fingerprints of Rice Nutritional Quality and the Concept of Raman Barcode.

The nutritional quality of rice is contingent on a wide spectrum of biochemical characteristics, which essentially depend on rice genome, but are also greatly affected by growing/environmental conditions and aging during storage. The genetic basis and related identification of genes have widely been studied and rationally linked to accumulation of micronutrients in grains. However, genetic classifications cannot catch quality fluctuations arising from interannual, environmental, and storage conditions. Here, we propose a quantitative spectroscopic approach to analyze rice nutritional quality based on Raman spectroscopy, and disclose analytical algorithms for the determination of: (i) amylopectin and amylose concentrations, (ii) aromatic amino acids, (iii) protein content and structure, and (iv) chemical residues. The proposed Raman algorithms directly link to the molecular composition of grains and allow fast/non-destructive determination of key nutritional parameters with minimal sample preparation. Building upon spectroscopic information at the molecular level, we newly propose to represent the nutritional quality of labeled rice products with a barcode specially tailored on the Raman spectrum. The Raman barcode, which can be stored in databases promptly consultable with barcode scanners, could be linked to diet applications (apps) to enable a rapid, factual, and unequivocal product identification based on direct molecular screening.

Effect of salt stress on proximate composition of duckweed (Lemna minor L.)

The shortage of conventional feedstuff is one of the rising issues faced by the developing countries of the world. To bridge the gap between supply and demand of the major feedstuff it is desirable to practice the use of non-conventional feed resources. Duckweeds are the aquatic macrophytes growing in stagnant water bodies that offer a choice to be used as an alternate feed. Before the use of any alternate feed, it is vital to know the nutritional composition of the feed under diverse environmental conditions. The objective of this study was to investigate the influence of salinity, abiotic stress, on the proximate composition of duckweed (Lemna minor L.). The experiment was laid out in Completely Randomized Design (CRD) with 3 repeats. Data was collected on protein, lipid, carbohydrate, and mineral contents. In the laboratory trial plants were grown under the saline condition of different concentrations ranging from 2 g NaCl L−1 to 12 g NaCl L−1 for a growing period of 20 days. The biomasses obtained were tested for proximate composition. ANOVA of the result exhibited a significant effect of salinity on the proximate composition of the plant. Protein residues of the plant started declining above the concentration of 4 g NaCl L−1 until the lowest value was obtained at 12 g NaCl L−1. Lipid composition showed more sensitivity to the stress with a sharp decline above 2 g NaCl L−1 having a minimum value at 12 g NaCl L−1. Carbohydrate contents increased with increasing salinity up to 6 g NaCl L−1 above which a decrease was observed. The highest accumulation of the macronutrients i.e., Ca, Mg, took place in the lower range of concentration of the salt. The percentage compositions of micronutrients such as Fe, Mn, and Zn percentage were reduced at a higher range of salinity while the optimum level was recorded in plants treated with 2 g NaCl L−1, followed by control. The total accumulation of both macro and micronutrients was higher in the plant material treated with a lower level of salt concentration, concluding a significant effect of salinity on proximate composition. As for the Indus water salinity level, the plant has the capacity of tolerance and can be grown without affecting its proximate composition.

Acúmulo de matéria seca e nutrientes pelo milho cultivado sob doses de formulados npk mineral e organomineral

O conhecimento da extração e acúmulo de nutrientes pelas plantas durante seu desenvolvimento auxilia na determinação das suas necessidades nutricionais e é relevante para aprimorar a recomendação de fertilizantes minerais e organominerais. Objetivou-se avaliar o efeito de doses de fontes de formulado NPK mineral e organomineral na produtividade de massa seca da parte aérea e no acúmulo de macronutrientes e micronutrientes pelo milho. O experimento foi realizado em vasos plásticos, dispostos a céu aberto, preenchidos com 25 L de solo, coletado de um Latossolo Vermelho distrófico, fase cerrado, na Fazenda Experimental do Instituto Federal Goiano, Campus Rio Verde - GO. O delineamento experimental utilizado foi de blocos ao acaso, em esquema fatorial 5x2, com quatro repetições. Os tratamentos foram cinco doses de formulado NPK 04-14-08 (0, 150, 300, 450, 600 kg ha-1do produto, equivalente para vaso) e duas fontes de fertilizantes: mineral e organomineral da formulação, 04-14-08. A colheita das plantas de milho foi realizada aos 75 dias após a semeadura, com corte do colmo rente ao solo. Nas plantas, foram realizadas avaliações de produtividade de massa seca da parte aérea e acúmulo de macronutrientes (N, P, K, Ca, Mg e S) e micronutrientes (Cu, Fe, Mn e Zn). A fonte organomineral proporcionou maior produtividade de matéria seca ao milho. O acúmulo de nutrientes seguiu a ordem decrescente N > K > Mg > Ca > S > P > Fe > Mn > Zn > Cu. A fonte organomineral, nas mesmas doses do formulado mineral, apresenta potencial de substituir as fontes minerais.

Phytoregulators and mineral nutrition interactions to the establishment of Passiflora alata seedlings

Crop plants have been widely used to discuss several physiological interactions between plant growth regulators (PGRs) and mineral nutrition. However, these physiological effects and their potentiality in non-domesticated species (wild species) are far to be elucidated. In this experiment, it is hypothesized that PGRs and mineral element availability interactions guaranteed improvements in plant development under low availability for the establishment of Passiflora alata Curtis (sweet passion fruit) seedlings. Plant growth and ionic accumulation of macro and micronutrients in leaf and root plant tissues of P. alata were examined. As expected, the ionic accumulation of some elements (N, P, S, B, and Cu) increased in response to a higher nutrient solution (ionic strength, IS) availability. The interactions IS × PGR were significant with respect to almost all the plant growth variables, besides the Zn in leaf and N, Zn, and B in roots. Comparing the treatment means, we verified that the plant growth responses and Zn in leaf were more similar between ISs when PGRs had been applied. Moreover, the use of PGR probably favors an adequate nutritional and hormonal balance, since it has guaranteed improvements even under low availability. It can be concluded that Passiflora alata Curtis that did not receive these phytoregulators are more variable in terms of nutrient content, and are therefore more susceptible to nutritional deficiencies.