Nutritional Fruit Research Articles

Structural characterization of polysaccharides recovered from extraction residue of ginseng root saponins and its fruit nutrition preservation performance.

Polysaccharides recovered from extraction residue of ginseng root saponins, i.e., ginsenosides-extracting residue polysaccharides (GRP), were separated into two fractions, GRP-1 and GRP-2. Fourier infrared and nuclear magnetic resonance spectra, as well as high-performance liquid chromatography and gel permeation chromatography measurements, showed GRP-1 was composed of mainly starch-like glucans and GRP-2, relatively a smaller portion, was a mixture of heteropolysaccharides composed of starch-like glucans, rhamnogalacturonan-I pectin, and arabinogalactans, and they had similar molecular weights. These results proved that the structure of GRP was not destroyed and GRP still maintained strong antioxidant activities. In addition, GRP coating on surfaces of fruit slowed their deterioration and maintained their nutritional effects. Correlation and PCA analyses on various quality and antioxidant parameters supported the above findings and a possible mechanism in fruit preservation was then proposed. Knowing the structural features and bioactivities of GRP gives insights into its application. Specifically, GRP served as an environmentally friendly coating that can be used to preserve the nutrients and other quality indicators of strawberries and fresh-cut apples, paving the way for future new approaches to food preservation using polysaccharides or other natural products.

Evaluation of nutrient elements contents of China’s main deciduous fruits and dietary exposure assessment

The mineral element characteristics of China’s 4 main deciduous fruits (apple, pear, grape, and peach) were studied to provide a scientific basis for fruit nutrition evaluation and fruit consumption. The element composition and their contribution towards recommended nutrient intake (RNI) and tolerable upper intake level (UL) among different populations were determined. The average contents of the 10 mineral elements followed the order K > P > Mg > Ca > Na > Fe > B > Cu > Zn > Mn. The 10 elements were significantly different among the four fruits (p < 0.05). Among the 10 elements, the highest contribution from four fruits to RNI was related to Cu (85.3%), of which apples and pears contributed 33.1% and 33.2%, respectively. The risk index (RI) of Cu from four fruits for all age groups ranged from 2.92% to 49.5% and the RI values of Ca, Fe, Mn, Zn were less than 16.0%, indicating that nutrient element exposure by four fruits intake was usually considered safe if consumed in reasonable amounts. The overall correct classification rate of four fruits by LDA was more than 85% which demonstrated that different kinds of fruits can be distinguished by mineral element contents.

Characteristics of Interspecific Hybridization and Inbred Progeny of Pumpkin (Cucurbita moschata Duch.) and Winter Squash (Cucurbita maxima Duch.)

Hybrid incompatibility and F1 hybrid dysgenesis in the interspecific hybridization between pumpkin (Cucurbita moschata Duch.) and winter squash (Cucurbita maxima Duch.) have been previously noted. For this reason, it is difficult to obtain F2 generations due to F1 sterility. However, back-crossing and add-crossing can be utilized to overcome these incompatibility barriers in interspecific hybridization. To date, few studies have focused on parental selection, the back-crossing process, and offspring characteristics related to interspecific hybridization. Hence, we explored the F1 seed acquisition rate, plant characteristics, and F2 generation fertility after interspecific back-crossing and add-crossing hybridization of C. moschata and C. maxima. Moreover, as a female parent, X-1 (C. moschata) yielded F1 seeds when crossed with winter squash (C. maxima) 10-04-3, 10-37, or 10-05-2. BC1F1 seeds and plants could be obtained with winter squash (C. maxima) as the recurrent parent. Some healthy F2 seeds and plants were obtained from the interspecific hybrids, including ZJ-13, ZJ-8, and ZJ-11. Further fruit nutrition quality analysis showed that the starch, polysaccharide, cellulose, and dry material contents of ZJ-7 and ZJ-8 were significantly higher than those of the parent pumpkin and winter squash lines. The bioflavonoid content of ZJ-8 was lower than that of its parents, and its soluble protein was at the median value. Meanwhile, the bioflavonoid content of ZJ-1 was lower than that of its parents, but its soluble protein was significantly higher. These results suggest that back-crossing and multi-crossing can overcome the barriers to interspecific crossing of C. moschata × C. maxima. Some interspecific hybrid fruits had nutritional contents much higher than those of their parent lines. Additionally, X-1 (C. maxima) was found to act as a bridge species in interspecific hybridization. Collectively, in this study, the barriers to interspecific hybridization of C. moschata × C. maxima were addressed through crossing methods and choice of parents, and the obtained results are expected to provide novel support for interspecific hybrid breeding between C. moschata and C. maxima.

Antioxidant and antibacterial activities of red (Hylocereus polyrhizus) and white (Hylocereus undatus) dragon fruits

Dragon fruit belongs to the genus Hylocereus of the Cactaceae family. There are two species that are commonly cultivated; Hylocerues polyrhizus and Hylocereus undatus that have the same red skin but different flesh colours, red and white respectively. Although from the same genus, the phytochemical contents and bioactivities of both fruits may not be the same. This study aims to compare the phytochemical contents, antioxidant and antibacterial activities of H. polyrhizus and H. undatus to help consumers better choose nutritional fruits and to explore potential natural preservatives. The fruit samples were extracted using 50% ethanol and later were subjected to phytochemical, antioxidant and antibacterial assays. The phytochemical contents were determined using Folin Ciolcalteu and aluminium chloride methods for total phenolic and total flavonoid respectively. The antioxidant activity was determined using diphenyl-picryl hydrazine (DPPH) and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Disk diffusion method was performed to evaluate antibacterial activities against two food-borne pathogens, Escherichia coli and Staphylococcus aureus. H. polyrhizus showed to contain significantly higher phenolic content (p&lt;0.05), while H. undatus had significantly higher flavonoid content (p&lt;0.05). Comparison of antioxidant activities in both fruit samples indicated higher activities were observed in H. polyrhizus and both fruit extracts showed inhibition zones against the tested bacteria with H. polyrhizus extract was able to inhibit at lower concentration. The results suggest that H. polyrhizus may have higher bioactivities compared to H. undatus due to the significantly higher phenolic content.

Hawthorn Rootstock (Crataegus spp.) Affects Scion Nutrition and Nutrient Composition of Fruit of Some Selected Quince (Cydonia oblonga Mill.) Genotypes

Hawthorn Rootstock (Crataegus spp.) Affects Scion Nutrition and Nutrient Composition of Fruit of Some Selected Quince (Cydonia oblonga Mill.) Genotypes

Biological, Nutritive, Functional and Healthy Potential of Date Palm Fruit (Phoenix dactylifera L.): Current Research and Future Prospects

Date palm cultivation is highly relevant, especially in the arid and semi-arid regions of the world, mainly due to the fact that it is considered an eco-efficient crop (based on its few growth requirements and the fact that it is economic and sustainable) that produces a nutritious fruit (date fruit). Recently, its implantation has rapidly spread to other areas of the world as a viable option to fight against the consequences of climate change, but also due to several health benefits associated with date fruit (pulp and seeds) which make them a potential source of functional food ingredients. This review provides detailed recent information on the nutrition, nutraceuticals and bioactive properties of date palm fruit (reinforced with in vitro and in vivo evidences) and their potential for developing novel and functional foods as a way to highlight the wide possibilities for this crop. Date fruits are rich in phytochemicals, such as phenolics, anthocyanin, carotenoids, tocopherols, phytosterols and dietary fiber, which have been linked with their biological activities (antioxidant, antibacterial, anti-inflammatory, prebiotic, anticancer and antitoxic properties) and are responsible for their use in the prevention and control of current diseases such as diabetes, cancer and gastrointestinal, cardiovascular and neurodegenerative diseases in industrialized countries.

Nutritional Analysis of Red-Purple and White-Fleshed Pitaya (Hylocereus) Species.

Pitaya is one of the most preferred and produced tropical fruit species recently introduced to the Mediterrranean region in Turkey. Due to its nutritional fruits with high economic value, the popularity of pitaya increases steadily in Turkey as an alternative crop. No detailed nutritional analysis has been undertaken in Turkey so far on fruits of the pitaya species. In this study, we determined and compared some nutritional parameters in fruit flesh of two pitaya (dragon fruit) species (Hylocereus polyrhizus: Siyam and Hylocereus undatus: Vietnam Jaina) grown in the Adana province located in the eastern Mediterranean region in Turkey. The individual sugars, antioxidant activity, total phenolic content, phenolic compounds and volatiles were determined for the first time in Turkey on two pitaya species. The results showed that total phenol content and antioxidant capacity are notably higher in red-fleshed fruits than white-fleshed ones and the predominant phenolic compound in fruits of both species was quercetin. The total sugar content and most of the phenolic compounds in fruits of two pitaya species were similar. A total of 51 volatile compounds were detected by using two Solid Phase Micro Extraction (SPME) fibers, coupled with Gas Chromatography Mass Spectrometry (GC-MS) techniques, and more volatile compounds were presented in the white-fleshed species. Total phenolic content (TPC) of the red-fleshed and white-fleshed pitaya species were 16.66 and 17.11 mg GAE/100 g FW (fresh weight). This study provides a first look at the biochemical comparison of red-fleshed and white-fleshed pitaya species introduced and cultivated in Turkey. The results also showed, for the first time, the biochemical content and the potential health benefit of Hylocereus grown in different agroecological conditions, providing important information for pitaya researchers and application perspective.

Terminalia catappa Linn.: A TREASURY OF PHARMACOLOGICAL BENEFITS

Terminalia catappa Linn. belonging to family Combretaceae is well known plant due to its nutritional fruit, bark, leaves and roots which are having medicinal properties. The various phytochemicals which are present in it are such as gallic acid, ellagic acid, corilagin, alkaloid, flavonoid, protein, phytosteroids, phenol and carotenoids are isolated form the different parts of the plant in various solvent systems. These isolated compounds have found to be possess numerous pharmacological properties such as antioxidant, antidiabetic, antimicrobial, antifungal, antinociceptive, hepatitis treatment, hypocholesterolemia, immunomodulatory, anthelmintic, antiviral, antiaging, anti-inflammatory, anticancer, anti-tumor, hematological, anthelmintic, aphrodisiac, wound healing. These all pharmacological activities cumulatively enhanced its traditional value and uses. In this review paper, the different pharmacological activities and their benefits are explored which are exhibited by different phytoconstituents present in different parts of the plant.

Changes in Ripening-Related Quality Traits of Long Shelf Life Tomatoes as Influenced by Water Deficit and Short-Term Postharvest Storage

The diversity preserved within the European long shelf life tomato landraces (LSL) is a unique source to design high quality tomato products better adapted to changing environmental conditions and, thereby, to reduce food losses. The adaptation of LSL to water deficit (WD) management practices and their postharvest keeping ability can be used as tools to concomitantly enhance fruit quality and sustainable production. In this study, we investigated the effect of WD conditions and the plant growing environment (open field vs. tunnel) on quality traits of two genotypes of the Penjar LSL variety (modern hybrid (MV) and landrace (LR)). Changes in ripening-related quality traits (fruit ethylene production, respiration rate, firmness, color, soluble solids content, titratable acidity and the content of antioxidants, as well as specific sugars and acids) in response to the different preharvest factors were evaluated at the time of harvest and after a short period of storage (30 days), following actual commercial practices. Significant differences among genotypes were encountered for most quality traits at the time of harvest and higher intra- and inter-environment heterogeneity was observed in the LR than in the MV genotype. In general, Penjar tomatoes exhibit a low physiological activity (ethylene production, 0.56–1.33 µL kg−1 h−1, respiration rate: 0.015–0.026 mg CO2 kg−1 h−1) at harvest. In both genotypes, WD increased to a different extent the fruit external color (redness, lightness) as well as the sensory (SSC) and nutritional (antioxidant capacity) fruit profiles. By contrast, the growing environment had little impact on most fruit quality traits. Postharvest storage only led to a slight reduction in the fruit respiration and ethylene production, lower sugars and acids content, enhanced color and no firmness changes. Overall, the results from this study demonstrate that selecting the appropriate genotypes is the most important step towards the design of high-quality LSL tomatoes, while WD and short-term storage can be used by farmers as a strategy to differentiate the product quality in specific market niches.

Promising Nutritional Fruits Against Cardiovascular Diseases: An Overview of Experimental Evidence and Understanding Their Mechanisms of Action.

Cardiovascular diseases (CVDs) are one of the leading causes of morbidity and mortality in both developed and developing countries, affecting millions of individuals each year. Despite the fact that successful therapeutic drugs for the management and treatment of CVDs are available on the market, nutritional fruits appear to offer the greatest benefits to the heart and have been proved to alleviate CVDs. Experimental studies have also demonstrated that nutritional fruits have potential protective effects against CVDs. The aim of the review was to provide a comprehensive summary of scientific evidence on the effect of 10 of the most commonly available nutritional fruits reported against CVDs and describe the associated mechanisms of action. Relevant literatures were searched and collected from several scientific databases including PubMed, ScienceDirect, Google Scholar and Scopus. In the context of CVDs, 10 commonly consumed nutritious fruits including apple, avocado, grapes, mango, orange, kiwi, pomegranate, papaya, pineapple, and watermelon were analysed and addressed. The cardioprotective mechanisms of the 10 nutritional fruits were also compiled and highlighted. Overall, the present review found that the nutritious fruits and their constituents have significant benefits for the management and treatment of CVDs such as myocardial infarction, hypertension, peripheral artery disease, coronary artery disease, cardiomyopathies, dyslipidemias, ischemic stroke, aortic aneurysm, atherosclerosis, cardiac hypertrophy and heart failure, diabetic cardiovascular complications, drug-induced cardiotoxicity and cardiomyopathy. Among the 10 nutritional fruits, pomegranate and grapes have been well explored, and the mechanisms of action are well documented against CVDs. All of the nutritional fruits mentioned are edible and readily accessible on the market. Consuming these fruits, which may contain varying amounts of active constituents depending on the food source and season, the development of nutritious fruits-based health supplements would be more realistic for consistent CVD protection.

Ethylene response factor AcERF91 affects ascorbate metabolism via regulation of GDP-galactose phosphorylase encoding gene (AcGGP3) in kiwifruit

Kiwifruit is known as ‘the king of vitamin C’ because of the high content of ascorbic acid (AsA) in the fruit. Deciphering the regulatory network and identification of the key regulators mediating AsA biosynthesis is vital for fruit nutrition and quality improvement. To date, however, the key transcription factors regulating AsA metabolism during kiwifruit developmental and ripening processes remains largely unknown. Here, we generated a putative transcriptional regulatory network mediating ascorbate metabolism by transcriptome co-expression analysis. Further studies identified an ethylene response factor AcERF91 from this regulatory network, which is highly co-expressed with a GDP-galactose phosphorylase encoding gene (AcGGP3) during fruit developmental and ripening processes. Through dual-luciferase reporter and yeast one-hybrid assays, it was shown that AcERF91 is able to bind and directly activate the activity of the AcGGP3 promoter. Furthermore, transient expression of AcERF91 in kiwifruit fruits resulted in a significant increase in AsA content and AcGGP3 transcript level, indicating a positive role of AcERF91 in controlling AsA accumulation via regulation of the expression of AcGGP3. Overall, our results provide a new insight into the regulation of AsA metabolism in kiwifruit.

Free Amino Acids Profile and Expression Analysis of Core Genes Involved in Branched-Chain Amino Acids Metabolism during Fruit Development of Longan (Dimocarpus longan Lour.) Cultivars with Different Aroma Types.

Simple SummaryIn this study, three longan cultivars, including non-aroma types ‘Shixia’ (SX), ‘Lidongben’ (LDB), and strong aroma type ‘Xiangcui’ (XC), were selected to analyze free amino acids (FAAs) variations at six distinct growth stages. The genome-wide identification and expression analysis of genes related to the branched-chain amino acids (BCAA) synthesis pathway were carried out. Results showed that thirty-six FAAs were identified, which increased drastically with fruit development until ripening. During the period of rapid fruit expansion, the aroma of XC changed from light to strong, and the contents of L-alanine and L-leucine were significantly higher than those of SX and LDB. The content of Leu was negatively correlated with the expression of DilBCAT1, -6, and -9 in three varieties, but positively correlated with DilBCAT16, indicating that these four genes may be responsible for the different synthesis and degradation of Leu among cultivars.Amino acids are important component of fruit nutrition and quality. In this study, three longan cultivars, including non-aroma types ‘Shixia’ (SX), ‘Lidongben’ (LDB), and strong aroma type ‘Xiangcui’ (XC), were selected to analyze free amino acids (FAAs) variations at six distinct growth stages (S1–S6). The genome-wide identification and expression analysis of genes related to the branched-chain amino acids (BCAA) synthesis pathway were carried out. Results showed that 36 FAAs were identified, and the total FAAs content ranged from 2601.0 to 9073.5 mg/kg, which increased drastically with fruit development until ripening. L-glutamic acid (Glu), L-alanine (Ala), L-arginine (Arg), γ-Aminobutyric acid (GABA), L-aspartic acid (Asp), L-leucine (Leu), hydroxyl-proline (Hypro), and L-serine (Ser) were the predominant FAAs (1619.9–7213.9 mg/kg) in pulp, accounting for 62.28–92.05% of the total amino acids. During the period of rapid fruit expansion (S2–S4), the aroma of XC changed from light to strong, and the contents of L-alanine (Ala) and L-leucine (Leu) were significantly higher than those of SX and LDB. Furthermore, a total of two 2-isopropyl malate synthase (IPMS), two 3-isopropyl malate dehydrogenase (IPMD), and 16 BCAA transferase (BCAT) genes were identified. The expression levels of DilBCAT1, -6, and -9 genes in XC were significantly higher than those in SX and LDB, while DilBCAT16 in XC was lower. The content of Leu was negatively correlated with the expression of DilBCAT1, -6, and -9 in three varieties, but positively correlated with DilBCAT16, indicating that these four genes may be responsible for the different synthesis and degradation of Leu among cultivars.

Pouteria Caimito nutritional fruit derived silver nanoparticles and core-shell nanospheres synthesis, characterization, and their oral cancer preventive efficiency

This study aimed to assess the synthesis of biogenic silver nanoparticles (BAg) and core–shell nanospheres (BAg@SiO2) from PC fruit extract using an eco-friendly method. Besides, these BAg and BAg@SiO2 are used to evaluate their oral cancer-preventive effectiveness against oral carcinogenesis. The BAg and BAg@SiO2 were characterized using physicochemical methods such as UV–Vis, FTIR, XRD, TEM, EDX, and ATR. The results indicated that the synthesized BAg and BAg@SiO2 both had small sizes, high stability, and no impurities. Cancer control animals showed 100% tumor and this was evidenced by the average mean volume was 386.17 mm3, and the tumor burden was 1340.53 mm3. The BAg and BAg@SiO2 treated cancer animals showed a significantly decreased tumor volume and burden compared to cancer control. The cancer animal buccal pouch showed a decrease in TBARS level, CAT activity, and SOD activity and an increase in GSH level, vitamin E level, and GPx activity. BAg-and BAg@SiO2-treated animals prevented these changes in peroxidation and antioxidant markers compared to near-normal animals. We conclude that the PC fruit extract is a favorable source for synthesizing biogenic silver nanoparticles and biogenic core–shell nanospheres. Additionally, BAg and BAg@SiO2 could exert better anticancer and antioxidant properties against oral cancer. BAg@SiO2 possessed better cancer preventive and antioxidant effects as compared to BAg because of their core-shell morphology. The core-shell morphology could be helped to sustain and trigger release of silver nanoparticles to the targeted cells. Future studies should investigate the mechanism of action of these effective BAg and BAg@SiO2 against oral carcinogenesis.

Potassium-Deficient Nutrient Solution Affects the Yield, Morphology, and Tissue Mineral Elements for Hydroponic Baby Leaf Spinach (Spinacia oleracea L.)

Nutrient supply in hydroponics can significantly influence the nutrition, taste, texture, color, and other characteristics of fruit and vegetable crops. Chronic kidney disease (CKD) is a global health problem that frequently restricts a patient’s consumption of high-potassium foods. CKD patients are advised to limit their consumption of many vegetables that are potassium (K)-rich. At the same time, reducing vegetable intake reduces the intake of healthy compounds such as vitamins, fibers and antioxidants, which are beneficial to CKD patients. In our study, we investigated the reduction of the K concentration in a hydroponic nutrient solution as a possible technique to decrease the K tissue concentration of baby leaf spinach, a dark green that is frequently recommended to be consumed in moderation for patients with CKD. A previously developed hydroponic fertilizer recipe that provides a platform to adjust individual nutrients was used to adjust K to 0, 10, 25, and 100% of the control K concentration. Tissue K levels were reduced by up to 91% with a consequent 61% reduction in dry weight and 76% reduction in fresh weight (yield) with respect to the control treatment. Overall, the results suggest that using a nutrient solution without K can significantly reduce K concentrations in baby spinach, although this will consequently reduce yields.

Nutritional quality, fruit shape and relationships among exotic and local Capsicum pepper genotypes in Uganda

Twenty-one hot pepper genotypes comprising of local (15) and exotic (6) types (C. annuum, C. frutescens and C. chinense) were characterized for selected fruit traits after propagation in a glasshouse at the Makerere University Agricultural Research Institute Kabanyolo in Central Uganda using a completely randomized design with three replicates. Ripe fruits were harvested and analyzed; traits evaluated were all significantly different at P&lt;0.05 with variations in quality attributes. The genotype OHA-B305-10 had the highest ascorbic acid content (128.86 mg/100 g) and is recommended for improvement of both local and exotic genotypes targeting the fresh market. Genotypes CAP0408-12 and UG2 WE0511-22, with highest total soluble solids (16.17 ºBrix) and dry matter content (28.59%), respectively should be used in improvements for industrial use or processing to products such as chilli powder or flakes. BRS-M205-04 with highest titratable acidity (1.04%) can be used in enhancing shelf life of genotypes with low titratable acids as well as for the fresh market. In spite of the intraspecific relationships among genotypes, significant differences were observed in their quantitative traits. These genotypes will, therefore, be useful in improving the quality of hot pepper fruit in Uganda.

Changes of bioactive components and antioxidant potential during fruit development of Prunus humilis Bunge.

Dynamic changes in flavonoid, total phenol, and antioxidant potential in different Prunus humilis accessions during fruit development stages were studied in order to provide a reference for the optimum harvest time for flavonoid extraction. 'Nongda 4', 'Nongda 5', 'DS-1' and '02-16' were selected as plant materials to determine the content of flavonoid, total phenol and antioxidant indices during six fruit development stages. Changes in total flavonoid content (TFC) and total phenol content (TPC) in different accessions of P. humilis were slightly different depending on the development stage of P. humilis fruit. TFC and TPC in 'Nongda 5' fruit showed a trend of continuous decline. There was a small increase in TFC and TPC from the young fruit stage to the stone hardening stage, followed by a decreasing trend, and then to the lowest level at the ripening stage of 'Nongda 4', 'DS-1', and '02-16' fruits. The trend of antioxidant capacity (ABTS, FRAP, DPPH) with the TFC and TPC of P. humilis fruit was basically the same, and the correlation analysis results showed that the TFC of P. humilis fruit was positively correlated with the antioxidant indices (P<0.01). Catechin (CC), rutin (RT), and quercetin-7-O-β-D-glucopyranoside (Q7G) were detected in all the fruit development stages of the four P. humilis fruits. Among them, catechin was the most abundant component, accounting for approximately 10%. Myricetin (MC) and quercetin (QC) were generally detected only in the early fruit development stage, but not in the later fruit development stage. Correlation analysis showed that the flavonoid components with TFC, TPC, and antioxidant indices differed between the different accessions. RT, CC, and liquiritigenin (LR) had a stronger correlation with TFC and antioxidant indices. Cyanidin-3-O-glucoside (C3G) was not detected until the coloring stage in two red P. humilis accessions ('Nongda 4' and 'DS-1'), and so it is better to choose a red P. humilis fruit to extract C3G at the ripening stage. Selecting an early stage of fruit development, especially the stone hardening stage, was important for extracting flavonoids, total phenols and other components. We believe that our results will provide basic information and reference for evaluation of fruit nutrition and health benefits, breeding of functional new varieties, and efficient utilization of P. humilis fruit.

Effects of Shade Net Colors on Mineral Elements and Postharvest Shelf Life and Quality of Fresh Fig (Ficus carica L.) under Rain-Fed Condition

Photoselective netting is well known for filtering the intercepted solar radiation, thus affecting light quality. While its effects on leaf mineral elements have been well investigated, how color netting affects fruit mineral nutrients remains elusive. This study was conducted to evaluate the effects of shade provided by blue and yellow nets on mineral nutrients of fig trees under rain-fed conditions. The experiment was arranged as a split-plot treatment in a randomized complete block design with three replications. Cultivars “Sabz” and “Siah” were covered with color nets or left uncovered (as the control group). The highest nitrogen content (8710 ppm) was recorded for cultivar “Sabz” covered with blue net. Color nets enhanced calcium concentration in cultivar “Siah”. Covering fig trees with yellow net increased magnesium content in cultivar “Siah” and phosphorus content in cultivar “Sabz”. Our observation showed the significant positive effect of photo selective nets on postharvest quality, by decreasing fig fruit weight loss and extending shelf life of fruits. In general, color nets as a new agro-technological approach can maintain fruit nutrition under rain-fed conditions and increase postharvest shelf life and quality of fresh fig.

Determination of fruit chemical contents of two plum cultivars grafted on four rootstocks

The study was aimed at assessing chemical composition of fruits of plum cultivars ʻČačanska Lepoticaʼ and ʻJojoʼ grafted on four rootstocks with different mechanisms of resistance to Plum pox virus (PPV): sensitivity, ʻWavitʼ and ʻWeiwaʼ and hypersensitivity, ‘Docera 6’ and ‘Dospina 235’. The cultivar significantly influenced on content of sugars and organic acids, with the highest values in cultivar ʻJojoʼ. The highest content of sucrose, sorbitol and total sugars were found in ʻWeiwaʼ, and all individual and total acids were higher in fruits from trees grafted on ʻWavitʼ. On the one hand ‘Čačanska Lepotica’ had a high content of malic acid, but on the other hand a low content of citric and fumaric acids, regardless of the rootstock. The most abundant phenolic compounds, phenolic acids and flavanols, were shown to be at the highest level in the combinations ʻČačanska Lepoticaʼ/ʻDocera 6ʼ and ʻJojoʼ/ʻWavitʼ, whereas less abundant phenolic compounds, flavonols and anthocyanins, were the highest in the combinations ʻČačanska Lepoticaʼ/ʻWavitʼ and ʻJojoʼ/ʻWeiwaʼ. In order to improve nutritive fruit quality and the technology of growing, as well as to delay the spread of PPV, rootstocks ʻWavitʼ and ʻWeiwaʼ can be recommended for further promotion in modern plum plantations.

Variation for Composition and Quality in a Collection of the Resilient Mediterranean 'de penjar' Long Shelf-Life Tomato Under High and Low N Fertilization Levels.

The ‘de penjar’ tomato (Solanum lycopersicum L.) is a group of local varieties from the Spanish Mediterranean region carrying the alc mutation, which provides long shelf-life. Their evolution under low-input management practices has led to the selection of resilient genotypes to adverse conditions. Here we present the first evaluation on nutritional fruit composition of a collection of 44 varieties of ‘de penjar’ tomato under two N fertilization levels, provided by doses of manure equivalent to 162 kg N ha–1 in the high N treatment and 49 kg N ha–1 in the low N treatment. Twenty-seven fruit composition and quality traits, as well as plant yield and SPAD value, were evaluated. A large variation was observed, with lycopene being the composition trait with the highest relative range of variation (over 4-fold) under both N treatments, and significant differences among varieties were detected for all traits. While yield and most quality traits were not affected by the reduction in N fertilization, fruits from the low N treatment had, on average, higher values for hue (5.9%) and lower for fructose (−11.5%), glucose (−15.8%), and total sweetness index (−12.9%). In addition, lycopene and β-carotene presented a strongly significant genotype × N input interaction. Local varieties had higher values than commercial varieties for traits related to the ratio of sweetness to acidity and for vitamin C, which reinforces the appreciation for their organoleptic and nutritional quality. Highest-yielding varieties under both conditions displayed wide variation in the composition and quality profiles, which may allow the selection of specific ideotypes with high quality under low N conditions. These results revealed the potential of ‘de penjar’ varieties as a genetic resource in breeding for low N inputs and improving the organoleptic and nutritional tomato fruit quality.

Calcium in the mineral nutrition of yellow passion fruit cultivated in lined pits and with saline water

ABSTRACT Nutritional status is an important tool in salinity management, because salt stress interferes with both the absorption and the assimilation of mineral nutrients by plants. The objectives of this experiment were to evaluate the effects of water salinity, lateral protection of pits against water losses and calcium doses on the leaf concentration of macronutrients and sodium of yellow passion fruit cv. BRS GA1. The treatments were arranged in a randomized block design in split plots in a 2 × (2 × 5) factorial scheme, corresponding to water salinity (0.3 and 4.0 dS m-1) in the main plot, and the combinations between lateral protection of pits (without and with) and calcium doses (0, 30, 60, 90 and 120 kg ha-1) in the subplots. Leaf concentrations of macronutrients and sodium were determined at the phenological stage of full flowering. Irrigation of yellow passion fruit with 4.0 dS m-1 water decreased the leaf concentrations of macronutrients. The lining of the pits compromised macronutrient concentration in the plants. Calcium fertilization is recommended for yellow passion fruit cultivated in Entisol with low calcium concentration at the dose of 60 kg ha-1, because it raises nitrogen and calcium concentrations in plants irrigated with non-saline water and magnesium and sulfur concentrations in those irrigated with saline water. Calcium attenuates salt stress because it promotes the accumulation of macronutrients in yellow passion fruit under saline conditions.