Search

Citrus trees, particularly oranges, are a highly significant plant genus due to their consumption as fresh produce and the multiple compounds derived from them, which are extensively used in the food, cosmetic, and pharmaceutical industries. Despite recent advancements, the understanding of metabolic processes in the Citrus genus remains limited, especially in the context of variable agricultural practices. This study aimed to investigate the metabolomic evolution in leaves of sweet orange (Citrus sinensis) cultivated under different conditions over two key developmental periods: pre-winter (t1) and spring sprouting and flowering (t2). Using proton nuclear magnetic resonance (H-NMR) spectroscopy, this research identified 27 key metabolites across five distinct cultivation treatments (T0, T1, T2, T3, T4), including amino acids, organic acids, and sugars, and their variation over time. T0 represents the traditional crop of the control plot, while T1, T2, T3, and T4 incorporate different strategies aimed at water-saving, such as the use of weed control mesh and subsurface drainage systems, all designed to improve profitability and crop efficiency under the same soil and climatic conditions. The treatments were evaluated for their impact on plant growth parameters such as height, trunk diameter, and flower production, with a focus on reducing water usage without compromising crop performance. The results indicate that the use of weed control mesh significantly improves plant growth, increases flower production, and stabilizes key metabolite levels, contributing to a concept termed “plant metabolomic homeostasis.” These findings are particularly relevant in regions like southeastern Spain, where water scarcity is a major concern. The study provides compelling evidence that the implementation of weed control mesh in orange cultivation can enhance water efficiency, promote healthier plant development, and maintain metabolic stability under variable growing conditions. These results suggest that such agricultural practices could be recommended for broader commercial application in citrus cultivation to improve sustainability and crop profitability.

Efficient boron removal from irrigation waters is crucial for sustainable agriculture, as elevated levels of boron can be toxic to many plants, limiting growth and crop productivity. In this context, the present study investigated the sorption equilibrium of boron using zeolites in two types of aqueous matrices: a synthetic solution containing only boron and natural irrigation waters. Through the application of various isothermal sorption models (Langmuir, Freundlich, Sips, Toth, Jovanovic, Temkin, Dubinin–Radushkevich, and Redlich–Peterson), the efficacy of zeolite for boron removal under controlled and real conditions was evaluated. The results indicated a notable difference in sorption behavior between the two matrices, reflecting the complexity and heterogeneity of interactions in the boron–zeolite system. In the synthetic solution, the Freundlich model provided the best fit (R2 = 0.9917), suggesting heterogeneous and multilayer sorption, while the Sips model showed high efficacy in describing the sorption in both matrices, evidencing its capability to capture the complex nature of the interaction between boron and zeolite under different environmental conditions. However, in natural irrigation waters, the Jovanovic model demonstrated the most accurate fit (R2 = 0.999), highlighting the importance of physical interactions in boron sorption. These findings underscore the significant influence of the water matrix on the efficacy of zeolite as a boron removal agent, emphasizing the need to consider the specific composition of irrigation water in the design of removal treatments. Additionally, the results stress the importance of selecting the appropriate isothermal model to predict boron sorption behavior, which is crucial for developing effective and sustainable treatment strategies. This study provides a basis for optimizing boron removal in various agricultural and industrial applications, contributing to the design of more efficient and specific water treatment processes.

Late-season varieties of mandarin (Citrus reticulata Blanco) have a high economic value, so their study, characterization, and comparison among different commercial varieties is of great interest for agriculture. Detailed metabolomic analysis of mandarin leaves can provide valuable information on agronomic characteristics, vegetative development, and tree response to abiotic and biotic stresses. In this study, an analysis of the main metabolites presents in the leaves of three late-season mandarin orange varieties (‘Afourer’, ‘Orri’ and ‘Tango’), cultivated under homogeneous conditions, was carried out using nuclear magnetic resonance (1H NMR) and multivariate statistical analysis techniques. The results show that organic acids and sugars are the metabolites with the highest presence in mandarin leaves, especially malate and sucrose. Ten amino acids and other metabolites such as choline and trigonelline were also detected. Metabolites such as asparagine and isoleucine were widely implicated in the metabolic pathways of the detected compounds. The ‘Orri’ variety showed significantly more differences in metabolite concentrations compared to the other two varieties studied. Malate and sucrose were shown to be the metabolites with the greatest significant differences between the varieties compared. From an agronomic point of view, the ‘Orri’ variety differs from the other two varieties because it has concentrations of metabolites that provide good resistance to abiotic and biotic stresses and fruits of higher quality and sweetness.

With a progressively decreasing availability of water for irrigation, the utilization of lower agronomic quality water sources is becoming more prevalent. Compounds such as sodium and boron, due to their impact on crop development and production, are gaining significance in these water sources. Finding novel methods to immobilize these compounds in irrigation water is a top priority in the global agricultural sector. This study focused on exploring the potential of natural zeolite, commonly used as a soil improver and as a sorbent for sodium and boron in natural agricultural waters. The zeolite exhibited favorable properties, including a surface area of 40 m2/g and a cation-exchange capacity of 1.8 mg/g. Using a central composite factorial design, the zeolite’s capacity to remove sodium and boron from irrigation water was investigated. The results demonstrated significant efficiency in boron removal, while sodium removal was limited, with occasional desorption episodes. Response surface analysis revealed optimal conditions for the removal of each cation. Additionally, adsorption kinetics and pH effects were explored, emphasizing the influence on sodium sorption. Kinetic models were applied, and the pseudo-first-order model proved suitable for describing the sorption kinetics. These findings enhance our understanding of zeolite efficacy in irrigation water purification, emphasizing the complexity of cation interactions in “complex” solutions.

The pomegranate (Punica granatum L.) attracts attention in studies for its nutritional and medicinal properties. However, a recurring issue in the literature arises due to the multidisciplinary nature of these studies, leading to a mistaken repetition of basic botanical terms. The problem stems from the misapplication of the term “aril” to the pomegranate seed, despite the fruit being exariled, signifying the absence of an aril. This confusion may be attributed to the sarcotesta’s appearance, resembling a complete aril, coupled with a lack of awareness in fields such as medicine, pharmacy, and cosmetics. This study specifically examines the Kingdom-variety pomegranate, due its economic importance in the fruit market. The fruits were evaluated at different developmental stages—initial, intermediate, and commercial. Magnification photography techniques were used to study the development state of the pomegranate fruits. The physiological studies confirm that the pomegranate seed constitutes the complete grain, with the juicy, sweet part surrounding it identified as the testa, not an aril. The findings underscore a persistent error in the existing literature, emphasizing the necessity for dissemination and education in future studies. A thorough grasp of pomegranate anatomy and precise use of terminology are indispensable for ensuring accuracy and rigor in scientific communication.

Mandarins are one of the most important citrus fruits in the world in terms of tons produced. The late-season varieties of mandarin have a great economic value due to their high production in a season with few mandarin varieties. The objective is to carry out a preliminary study of characterization and comparison of the morphological and biochemical properties of the late varieties ‘Afourer’, ‘Tango’, and ‘Orri’. The characterization consisted of physicochemical parameters related to the quality of the fruits, highlighting the total antioxidant activity using ABTS and DPPH, the organic acids and sugars using HPLC and the metabolomics of the juice by 1H-NMR. Afourer’ mandarins were heavier and larger (120.75 g, 67.60 mm) than the other two varieties studied. Mandarins of the ‘Orri’ variety showed a different organic acid profile compared to the other varieties studied, and a higher amount of sugars (13.49 g/100 mL). ‘Tango’ variety mandarins grown on the Forner-Alcaide rootstock stood out for having a larger weight (113.52 g), a more intense color, and a greater amount of phenolic compounds (966.85 mg AGE/L Forner) than the fruits grown on Citrus macrophylla. The metabolomics analysis showed that these mandarin varieties had mainly non-essential amino acids.

Blood oranges have high concentrations of bioactive compounds that are beneficial to health. In Europe, the cultivation of blood oranges is increasing due to their excellent nutritional properties. In Citrus crops, rootstocks play an important role in juice and can increase the content of bioactive compounds. The morphological, qualitative and nutritional parameters were analyzed in cultivars ‘Tarocco Ippolito’, ‘Tarocco Lempso’, ‘Tarocco Tapi’ and ‘Tarocco Fondaconuovo’ grafted onto Citrus macrophylla and Citrus reshni. ‘Tarocco Lempso’ grafted onto Citrus macrophylla obtained the highest values of weight (275.78 g), caliber (81.37 mm and 76.79 mm) and juice content (162.11 g). ‘Tarocco Tapi’ grafted onto Citrus reshni obtained the most interesting qualitative parameters (15.40 °Brix; 12.0 MI). ‘Tarocco Lempso’ grafted onto Citrus reshni obtained the most intense red juice (a* = 9.61). Overall, the highest concentrations of primary metabolites were in proline, aspartate, citric acid, and sucrose. The results showed that ‘Tarocco Ippolito’ juice grafted onto Citrus reshni had the highest levels of total hydroxycinnamic acids (263.33 mg L−1), total flavones (449.74 mg L−1) and total anthocyanins (650.42 mg L−1). To conclude, ‘Tarocco Lempso’ grafted onto Citrus macrophylla obtained the best values of agronomic parameters, and the cultivars grafted onto Citrus reshni obtained significantly higher concentrations in primary and secondary metabolites.

Lemon is one of the most significant crops globally, with annual production exceeding 20.8 million tons in 2021. Spain leads the production in Europe with over 62% of lemon production (1.17 million tons in 2021). This study evaluated the real impact of cultivation conditions (rootstock and culture medium) on the compositional characteristics of ‘Verna’ lemons (peel and juice) using 1H-MNR metabolomic identification techniques and multivariate analyses. Twenty metabolites were identified in both the peel and juice samples. Arginine, phenylalanine, ethanol, and trigonelline were absent in the peel samples but present in all the juice. On the other hand, the metabolites asparagine, glutamate, formate, and malate were present in the peel samples but absent in the juice. The analysis of the results indicates that the rootstock had a significant impact on the metabolites related to the energy metabolism of the plant, which directly affects the development of fruits and the influence of the culture conditions (rootstock and culture medium) on the plant’s adaptive response and modification of metabolic pathways.

The increasingly evident threat of depletion of world peat bogs is encouraging the search for and study of alternative agricultural substrates that can fully or partially replace peat, guaranteeing food supply (quality and quantity). On the other hand, the identification of the potential for the reuse of waste from relevant economic activities has increased in recent years, mainly motivated by the change to a sustainable circular economy, as is the case of port sediments. Taking into account that significant volumes of dredged port sediments are generated annually so that ports can maintain their economic activity, it is necessary to find objective, sustainable and safe reuse alternatives. In this sense, the objective of this study was to study the response of the “Purple Queen” pomegranate when grown with dredged port sediment. For this, the fruit production (kg), number of fruits (fruits tree-1), fruit weight (g), and seed yield (%) aiming to verify the correct tree development were evaluated. In addition, a 1H-NMR foliar metabolomic study for the three most relevant phenological phases was performed (flowering, fruit development, and post-harvest) to identify metabolic changes in trees. In total, 29 metabolites were identified; among them, 11 were amino acids, 6 organic acids, 5 sugars, and 7 secondary metabolites. The good agronomical development of the trees and fruits indicated the potential for using the dredged sediment as an agricultural substrate. On the other hand, the results revealed that the greatest variability in the metabolomic study occurred between the phenological phases and a lower variability is explained by the substrates used.

The increase in maritime trade and its global economic importance have forced port management actors to carry out the periodic dredging of their sediments to maintain an adequate depth for the passage of large ships to maintain their operation and competitiveness. During the dredging process, large volumes of port sediment are generated. Dredged port sediment is currently considered a waste material and its disposal is regulated. Finding ways to safely reuse port sediments is necessary for sustainable development. In this study, a life cycle assessment (LCA) methodology was applied to identify the environmental impact of port sediments when used as a culture medium for lemon trees. A total of 90 lemon trees (Citrus limon L. Burm var ‘Verna’) were used in the trial. The trees were grown under controlled conditions using three substrates, with different portions of peat and port sediment (25%, 50%, and 75%) to identify the real impacts of the culture media on the growth process. The LCA was calculated and analyzed according to the ISO 14040:2006 standard, using the SimaPro v. 9.3 software (PRé Sustainability B.V, Amersfoort, The Netherlands). The functional unit defined for the three-culture media was 1 kg of lemons. The LCA results showed a significant increase in the environmental impact of lemon cultivation proportional to port sediment content (75%), due to the decrease in fruit production caused by the sediment. However, the least impact was identified for the culture medium at 50% peat and 50% port sediment. The greatest impacts were more related to crop management rather than the port sediment content. The results showed that the use of the port sediment, mixed with other substrates as an agricultural medium amendment, is a viable option for lemon growers.

Due to its high content of bioactive compounds, the lemon is considered one of the most relevant species around the world. Its great economic importance is motivated, in addition to its fresh consumption, by its applications in the medical, pharmaceutical, and food industries, etc. However, the chemical and nutritional composition of lemon is not constant and can be influenced by external factors such as variety, weather conditions, crop management, etc. Determining the compositional variations of the fruit, essential to defining its potential use, was the main objective of this study. The physicochemical characteristics of the ‘Verna’ lemon were studied as a function of two controlled variables, the growing substrate and the rootstock. For this, 90 lemon trees were cultivated in three rootstocks and three different culture media. Lemon trees cultivated with 50% sediment/peat mix substrate presented a higher total production (590 lemons and 90.53 kg) while this production was 80% lower on trees cultivated with 75% marine sediment. Citrus macrophylla and Citrus aurantium/Citrus sinensis rootstocks showed a significantly higher production than the Citrus aurantium. All the fruits presented a predominantly yellow color appropriate for the market (0 < CI < +5). Nutritional and chemical parameters were consistent with data reported for the ‘Verna’ clones. All the obtained lemons were suitable for marketing and consumption both in fresh and processed forms. The results indicated the limited influence that the studied variables have on the quality parameters of lemon fruits, but they also could confirm the potential of marine sediment as a culture substrate.

The elaboration and definition of “metabolic fingerprints” can subsidize both the identification and determination of plant varieties, as well as the increase in knowledge about the responses and adaptations of plants to external and/or internal factors. The lemon tree (Citrus limon Burm.) is one of the most important crops in the Spanish southeast and is often consumed around the world. Although the study and characterization of its fruits are common due to its economic interest, its leaves are limited to specific functionalized studies related to the objective of the work (extraction of essential oils, stabilizing agent, aromatic extracts, etc.). So, this study aimed to identify the primary and secondary metabolites of Citrus limon Burm. (‘Verna’ variety) leaf samples cultivated under different conditions (three rootstocks and three culture media). In total, 19 metabolites were identified for all samples, of which 9 were amino acids, 5 organic acids, 3 sugars and 2 intermediate metabolites. The results pointed to a limited influence, both of the substrate and of the crop rootstock, on the metabolomic differentiation of lemon leaves. Knowledge and foliar metabolomic differentiation can offer important information that supports the application of crop foliar treatments but also helps in the management of diseases and pests.

Although most of the published articles generalize with the fruit of the fig tree (Ficus carica L.), the differentiation between fig and breba is increasingly common in the bibliography. In this regard, keep in mind that the fig tree generally produces two crops a year, the parthenocarpic breba, also called as early fig, and the main non-parthenocarpic crop, the fig proper. In this study, four brebas varieties (‘Colar’, ‘SuperFig1’, ‘Cuello de Dama Negro’ and ‘San Antonio’) were selected in order to identify compositional, nutritional, and chemical diversity. These varieties were chosen for their commercial relevance in Spain. Color (internal and external), fruit and peel weight, size, pH, total soluble solids (TSS), titratable acidity (TA), maturity index (MI), sugar, and organic content were determined for all the breba fruits samples. In addition, polyphenolic profile, amino acids, and volatile aromatic compounds were also identified. The varieties ‘Colar’ and ‘SuperFig1’ showed the highest fruit weight and size, while ‘Cuello de Dama Negro’ presented the higher pulp yield. The higher organic acid and sugar contents were determined for ‘SuperFig1’ and ‘Cuello de Dama Negro’, respectively. Although in low concentrations, the phenolic compound quercetin 3-(6-O-acetyl-beta-glucoside) and the amino acid tyrosine were only detected in the ‘’Cuello de Dama Negra’ and ‘SuperFig1’ fruits, respectively. Of the eighty volatile aromatic compounds identified, only eight were common in four varieties. An important knowledge gap was identified in relation to the characterization of the two Ficus carica L. crops, that is, the differentiation and specification in the literature when working with brebas and/or figs.

The Spanish Mediterranean region concentrates the largest producers of lemons (Citrus limon Burm. f.) at the national level where the 98.4% of the cultivated area of lemons corresponds to the varieties “Verna” and “Fino”. In this study, the morphological and chemical variations of the fruits obtained in five variety/rootstock combinations were investigated in order to determine the influence and impact of the rootstock on the physicochemical properties of the fruits. The assay was carried out using three lemon varieties (“Fino 95”, “Fino 49” and “Verna”) grafted onto two different rootstocks (Citrus macrophylla and Citrus aurantium). The varieties were selected due to be consolidated commercial varieties, while the rootstocks are the most commonly used in the world. Both the morphological characteristics of the fruits (colour, weight, size) as well as their physicochemical characteristics (total soluble solids, titratable acidity, maturity index, antioxidant activity, sugars, and organic acids) were evaluated. Based on the results, the lemons with the best physicochemical and the best compositional characteristics were obtained in the “Fino 95” and “Fino 49” lemons grafted onto C. aurantium rootstock presented the highest quality fruits.