Measuring the Influence of Key Management Decisions on the Nitrogen Nutritional Status of Annual Ryegrass-Based Forage Crops

Publisher Copyright: © 2024 by the authors. The APC was funded by national funds through the Fundação para a Ciência e a Tecnologia, I.P. (Portuguese Foundation for Science and Technology) by the project UIDB/05064/2020 (VALORIZA—Research Centre for Endogenous Resource Valorization) and by national funds from Fundação para a Ciência e a Tecnologia (FCT), Portugal, through the research unit UIDP/04035/2020 (GeoBioTec).Increasing nitrogen use efficiency (NUE) by improving agricultural practices and soil knowledge, and implementing precision agriculture, is essential to reduce the overuse of fertilizers and increase nutrient retention. This study aimed to optimize N management in agriculture by establishing a critical N dilution curve (CNDC) and analyzing variations in NUE and the N nutrition index (NNI) among different crops under various treatments. Using a Bayesian model, the CNDC was determined as %Nc = 3.63 × PDM−0.71. The results showed that plant dry matter (PDM) and plant N content (PNC) varied significantly with crop type and sampling moments. Strong positive correlations are presented by PDM with N uptake (NUp) (0.89) and NNI (0.88), along with an inverse correlation with critical N concentration (−0.95). The study found that crops under irrigation conditions had higher NUp and higher NNI. This study provides valuable insights into the influence of key management decisions on the N nutritional status of annual ryegrass-based forage crops. The results highlight the critical role of accurate and conscious decision-making in improving NUE and crop yields, emphasizing the complex interactions between biomass production and N dynamics in crops. The conclusions allow significant benefits to be realized, contributing to the sustainability of agricultural systems.publishersversionpublishe

Production and characterization of green and black olive paste using cream of animal and vegetable origins

Now-a-days the quest for foods with high flavonoid polyphenols content, lower fat concentration and relative high proportion of monounsaturated or polyunsaturated fatty acids is increasing. Following this tendency green and black olive pastes applying soy cream or cream of animal origin were produced equating a subsequent industrial output, and the rheological, physicochemical and sensory characteristics of were characterized. It was found that the cohesiveness, adhesiveness and hardness of the black olive paste having cream of animal origin showed minimal values. Among samples the moisture varied between 67.15 -72.16% and the inorganic residue of the black olive pastes were also significantly lower from the green olive pastes. Minimum and maximum pH values were measured in green olive paste having soy cream and black paste with cream of animal origin, respectively. The crude fat showed significant differences among the olive pastes, whereas the protein content did not vary significantly. The colour of the black paste with cream of animal origin and soy were slightly orange, whereas the green paste remained green. The sensory analysis of the black olive paste including cream of animal origin showed lower average values for consistency and appearance attributes but the opposite occurred with the salty taste and overall assessment. Concerning to the aroma, the black olive pastes showed the highest values, while the green olive pastes kept similar values. It is concluded that the higher pH of the black olive pastes in conjunction with the water contents limits the shelf life and clearly pointed the need a careful microbial control. Considering that the colour parameters of a food is the first contact point of the consumer, these descriptors in the green olive pastes also seemed to have better acceptance, whereas preferences did not followed healthy options

Characterization of Gluten-free Bread Prepared From Maize, Rice and Tapioca Flours using the Hydrocolloid Seaweed Agar-Agar

Disponível em livre acesso no sítio do DOAJ em http://recent-science.com/indexThis work aims to check the rheological, physicochemical and sensory characteristics of gluten-free bread produced with corn, rice and tapioca flours, using the hydrocolloid seaweed agar-agar. Relatively to wheat bread, it was found that the pH was slightly lower in gluten-free bread. In the crust only the brightness remained significantly different between both bread types, but in the kernel, the parameters a*,b* and L* diverge significantly. The toughness as well as the force of penetration and cutting were also significantly different between both bread types. The hedonic evaluation showed that the panellists prefered bread with gluten but the quantitative descriptive analysis did not reveal a clear pattern. The overall assessment pointed that bread with gluten has a greater acceptance by consumers, while gluten-free bread is considered nice in the opinion of the penallists

The uptake of macronutrients by an active silicon accumulator plant growing in two different substrata

Pennisetum clandestinum (Graminae/Poaceae) an active Si-accumulator, was cultivated in two different substrata, both with reduced Si solubility. Plants growing in organic-rich soils contained much less Ca, K, Na and Si, than species growing in sandy soils. Although the highest macronutrient concentrations were associated to the highest Si levels in the organs of P. clandestinum, the R correlation values indicate that Si does not influence the internal balance and the uptake of these elements. In ca 65% of the cases roots have the highest average values regardless of the type of culture, while the contents of Mg in the shoots and roots of P. clandestinum were generally not significantly different (P>0.05). A significant decline of the macronutrient levels associated to the shoots and roots of P. clandestinum was observed from the 4th to the 6th month assay, especially for Ca in both organs, while for Mg and Na the decline is focused mainly in the shoots; K and Si decline is generally below 10%. When average values of Si in shoots and roots of plants collected from organic- rich and sandy soils were plotted against the average concentrations of Ca, K, Mg and Na in the same organs, weak but positive R correlation values were obtained - the highest R values were observed for Na and K and the lowest for Ca and Mg, regardless of the culture. Exception for the high R value observed for K, although the influence of Si on the K status in the whole plant is time-depending - R values, diminished from the 4th to the 6th month, as it happens in the majority of the cases. In conclusion, P. clandestinum can grow well and healthily in substrata with acid pH values and high carbonate content and low solubility of Si suggesting that the definition of the essentiality of Si, even in a Si-accumulator plant is still a matter of great controversy.publishersversionpublishe

An integrated chemical and technological approach for assessing Portuguese wheat flours quality and lengthening bread shelf-life

UID/GEO/04035/2019 UID/AGR/04129/2019The current trend of large-scale bread production is to facilitate processing at an industrial level, considering the use of flour mixtures with different chemical and technological parameters and incorporating food additives. Accordingly, costs can be minimized, whereas the quality and the shelf-life of the final product might increase, but a full characterization of the flours that must be used and the selection of the food additives to be incorporated into the dough is required. In this context, three Portuguese wheat flour varieties were evaluated (FariRamos, Nacional and AJMiranda), as well as two types of food additives with the aim to increase bread shelf-life. In these flours, the levels of K, S, P, Ca and Cl prevailed, but the moisture and ash contents of FariRamos were the highest and lowest, respectively. The colour of all flours was generally within the desired standard values. Nacional flour contained a higher fat content, but all the flours showed a higher relative abundance of linoleic acid (C18:2), followed by palmitic acid (C16:0) and oleic acid (C18:1). AJMiranda flour revealed a higher content of wet gluten and protein, but the SDS sedimentation index showed a higher value in the FariRamos flour. The fall index, which directly monitors the activity of the α-amylase enzyme, showed a lower value in AJMiranda and Nacional. Through farinograph and alveographyc analysis it was found that FariRamos has a tenacious gluten, but AJMiranda and Nacional had a balanced gluten, yet all of them can be classified as medium flours. Bread making with a mix of FariRamos, AJMiranda and Nacional flours and incorporating preservative food additives revealed the highest shelf-life (11-days) with methyl p-hydroxybenzoate [0.05 %] and benzoic acid [0.1 %], but the colour of the breads showed a relationship of intensity of white colour that depended on the additive used. At the end of the shelf-life, molds of the Eurotium, Trichoderma and Cladosporium genera developed in the bread. It was concluded that the chemical and technological approach applied in the characterization of the flour varieties, can be directly used to define the quality and shelf-life in the bakery industry, allowing the establishment of minimum commercialization prices.publishersversionpublishe

Nutritional profile of the Portuguese cabbage (Brassica oleracea L var. costata) and its relationship with the elemental soil analysis

The economic and financial crisis has increased the number of urban horticulture on lands close to present or past industrial areas. "Tronchuda" or the Portuguese cabbage (Brassica oleraceae L var. costata DC) was studied because of its importance in Portuguese diet. It belongs to a number of economically significant horticultural crops (Brassica species), which are also known to be nutritionally well-balanced vegetables. "Tronchuda" produced in urban horticultures from 4 regions of mainland Portugal was studied for its nutritional profile along with elemental soil analysis of each sampling site. This study revealed significant interactions between essential elements in soil and plant leaves - the edible part of the plant for human nutrition. In general, these organs contained poor concentrations of Fe and Si, while Mn is absent, regardless of the sampling sites. Conversely, Ca levels were abundant with values ranging between 3.3% and 3.9%. Soils from CAP showed a soil nutrient exhaustion of Fe, Mn and Mo, although the highest protein and sucrose contents in the leaves was observed in plants growing in those soils. Protein, lipids and carbohydrates concentrations differed according to sampling site, reflecting different production practices.publishersversionpublishe

Foliar Spraying of Solanum tuberosum L. with CaCl2 and Ca(NO3)2: Interactions with Nutrients Accumulation in Tubers

Calcium is essential for plants, yet as its mobility is limited, the understanding of the rate of Ca2+ accumulation and deposition in tissues of tubers, as well as the interactions with other critical nutrients prompted this study. To assess the interactions and differential accumulation of micro and macronutrients in the tissues of tubers, Solanum tuberosum L. varieties Agria and Rossi were cultivated and, after the beginning of tuberization, four foliar sprayings (at 8–10 day intervals) with CaCl2 (3 and 6 kg ha1) or Ca(NO3)2 (2 and 4 kg ha1) solutions were performed. It was found that both fertilizers increased Ca accumulation in tubers (mostly in the parenchyma tissues located in the center of the equatorial region). The functioning of the photosynthetic apparatus was not affected until the 3rd application but was somewhat affected when approaching the end of the crop cycle (after the 4th application), although the lower dose of CaCl2 seemed to improve the photochemical use of energy, particularly when compared with the greater dose of Ca(NO3)2. Still, none of these impacts modified tuber height and diameter. Following the increased accumulation of Ca, in the tubers of both varieties, the mean contents of P, K, Na, Fe, and Zn revealed different accumulation patterns. Moreover, accumulation of K, Fe, Mn, and Zn prevailed in the epidermis, displaying a contrasting pattern relative to Ca. Therefore, Ca accumulation revealed a heterogeneous trend in the different regions analyzed, and Ca enrichment of tubers altered the accumulation of other nutrientsinfo:eu-repo/semantics/publishedVersio

Mineral Monitorization in Different Tissues of Solanum tuberosum L. during Calcium Biofortification Process

Funding Information: This work received funding from PDR2020-101-030719 and the Fundação para a Ciência e a Tecnologia, I.P. (FCT), Portugal, through the research units UIDP/04035/2020 (GeoBioTec), UIDB/00239/2020 (CEF), and UID/FIS/04559/2013 (LIBPhys). This work was further supported by the grant of the Fundação para a Ciência e Tecnologia (FCT) UI/BD/150806/2020. Publisher Copyright: © 2022 by the authors.Calcium is one of the 16 essential elements for plants, being required as Ca2+ and being involved in several fundamental processes (namely, in the stability and integrity of the cell wall, the development of plant tissue, cell division, and in stress responses). Moreover, Ca plays an important role in potato production. In this context, this study aimed to monitor the culture development (in situ and using an unmanned aerial vehicle (UAV)) and the mineral content of four essential elements (Ca, P, K, and S) in different organs of Solanum tuberosum L. (roots, stems, leaves, and tubers) during a calcium biofortification process, carried out with two types of solutions (CaCl2 and Ca-EDTA) with two concentrations (12 and 24 kg∙ha−1). The calcium content generally increased in the S. tuberosum L. organs of both varieties and showed, after the last foliar application, an increase in Ca content that varied between 5.7–95.6% and 20.7–33%, for the Picasso and Agria varieties, respectively. The patterns of accumulation in both varieties during the biofortification process were different between the variety and mineral element. Regarding the quality analysis carried out during the development of the tubers, only the Agria variety was suitable for industrial processing after the last foliar application.publishersversionpublishe

Efeitos do Excesso do Cobre em Plantas de Arroz - Aspectos Bioquimicos, Fisiologicos e Ultra-estruturais

Rice (Oryza sativa L. cv. Safari) plants were grown over a 30-day period in a nutrient solution containing increasing Cu concentrations (0.002, 0.01, 0.25, 1.25 and 6.25 mg/l). In total tissues the average concentration of Cu was 35.1 ug/g (dw) Cu at the threshold toxicity a biphasic kinetic pattern was found for Cu up take rates, with a transition phase occurring at metal concentrations between 0.5 and 0.25 mg/l. Although the correlation between Cu and N, P, K, Ca, Mg, Zn, Fe, Mn, B, Mo, Na and Al accumulation might be complex, it seems to depend on its interations at the level of the net uptake rate. In the roots, Cu concentration seems to be related metionine and/or histidine concentrations, in 30 and 8.5 kDa proteins (as well as in 11 and 12 kDa polypeptides in 6.25 mg/l Cu treatment) being immobilized in the vacuoles. In the shoots excess Cu seems to occur in a form or suborgenellar distribution which does no inhibit acid phosphate and cytocrome creductase activities and at least in part, it accumulates in the vacuoles and possibility sticks to the tonoplast. In both root and leaf tissues excess Cu decreases the conversion of SAM to ACC. Concerning to roots it is also suggest that the variations triggered excess Cu on root growth might be explained through the interaction among Cu uptake mechanism(s), plasma membrane H"+ ATPase and root membrane permeability. In the shoots it seems that non lethal toxic copper concentrations stimulate ascorbate, diamine and o-diphenol oxidase activities which might inhibit the biomas production. Furthermore, it was found that increasing Cu concentration decreasing protein contents by affecting acid RNAse activity. The decrease of Mn and Fe concentration (triggered by excess Cu) seems to inhibit the syntesis of PT, PTF and PCh(ide) therefore inducing the decrease of carotenoids and chl concentrations, however, the sharp inhibition of Rubisco as well as inhibition at the level of the antenna chl a molecules of PSII might explain the observed decrease of net photosynthesis. Excess Cu also seems to inhibit the photo-synthetic electron transport mainly before the DPC donation site and, furthermore, decrease the contents of Pc and cyt f, whereas the PQ concentration sharply increased additionally, the leaf capacity for reduction of nitrate to amonia might also be primarily limited by capacibility of the chloroplast photo-chemical reactions to generate reducing power. With Cu levels greater than 0.25 mg7l the poly-peptide bands with apparent molecular weights of 42/41, 33/32, 21/20 and 19/18 kDa decreased. Furthermore, the use of a discontinuous SDS buffer system gel elctrophoresis showed a decreased of the 56/55, 55/54, 26 and 22 kDa bands with increasing Cu concentrations, along with the disappearence of the 16.5, 14.5 and 12 kDa bands. After the 0.25 and 12 kDa bands. After the 0.25 mg/l Cu treatment two bands having pl's 5.5 and 5.18 are replaced by a four different ones (ol's 6.7, 6.05, 5.35, 5.25). Cu toxicity might also block the intrachloroplastic peroxidase system trough a mechanism linked to ethylene biosynthesis. PC, MGMG and DGDG are the membrane components mainly affected by peroxidation which is coupled to an increase of the linolenatehydroperoxide concentrationAvailable from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1200 Lisboa / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga