Search Results (6)

The aim of this study was to investigate the differences between Castanea sativa Mill. and Castanea crenata Siebold & Zucc. × Castanea sativa Mill. in rooting ability in relation to endogenous levels of auxin, auxin cofactors and inhibitors that influence rooting success. Leafy cuttings of the two commercial cultivars ‘Marsol’ and ‘Maraval’ (Castanea crenata × Castanea sativa) and the native accession ‘Kozjak’ (Castanea sativa) were analyzed. Endogenous indole-3-acetic acid (IAA) concentration was assessed at the beginning of propagation (day 0); in addition, strigolactones, flavonoids, rooting ability and quality were assessed 120 days after. The concentration of endogenous IAA in ‘Maraval’ (324.34 ± 28.66 ng g⁻¹) and ‘Marsol’ (251.60 ± 35.44 ng g⁻¹) was significantly higher than in ‘Kozjak’ (112.87 ± 35.44 ng g⁻¹). The best rooting result was observed with the genotypes ‘Maraval’ (100.00 ± 0.00%) and ‘Marsol’ (90.48 ± 6.15%). A significantly lower strigol concentration was observed in the roots of ‘Maraval’ (75.54 ± 17.93 ng g⁻¹) compared with other genotypes. The total flavonoid concentration in ‘Maraval’ was significantly higher (2794.99 ± 187.13 μg g⁻¹) than in ‘Kozjak’ (1057.38 ± 61.05 μg g⁻¹). Our results indicate that the concentration of endogenous IAA has a significant influence on rooting success. The results further indicate that in the case of flavonoids and strigolactones, not only the individual compounds but also their ratio is important for rooting success. Correlation coefficients calculated between analyzed compounds and rooting success point toward specific functions of flavonoids and strigolactones in the rooting of Castanea that need to be functionally analyzed. Full article

The phytochemical characterization of Castanea spp. fruits is very important for the development of effective strategies for the biodiversity conservation and traceability of chestnuts, as the chestnut is one of the most important Italian and European nut and forest species. In this study, several cultivars of C. sativa (sweet chestnuts and “marrone-type”), C. crenata, and hybrids of C. sativa × C. crenata were characterized by spectrophotometric (Folin–Ciocalteu assay for the total polyphenolic content and ferric reducing antioxidant power test for the antioxidant capacity) and chromatographic (high-performance liquid chromatography coupled to a diode array UV-Vis detector) protocols to define their phytochemical composition and nutraceutical properties. The phytochemical results were then used to build a multivariate statistical model (by principal component analysis) and obtain an effective and rapid tool to discriminate unknown cultivars (i.e., no information about their origin) belonging to different species. The multivariate approach showed that the genotype was a significantly discriminating variable (p < 0.05) for the phytochemical composition. Polyphenols (in particular, phenolic acids and tannins) have been identified as the main bioactive classes with the highest discriminating power among the different genotypes. The total polyphenol content (TPC) and antioxidant capacity (AOC) showed a rich presence of bioactive compounds (74.09 ± 15.10 mg_GAE 100 g⁻¹ DW and 11.05 ± 1.35 mmol Fe²⁺ kg⁻¹ DW, respectively), underlining the potential health benefits and functional traits of chestnuts. The principal component analysis applied to phytochemical variables has proved to be an excellent and effective tool for genotype differentiation to be used as a preliminary method for identifying the species of Castanea spp. fruits with an unknown origin. The present study showed that a multivariate approach, based on phytochemical data and preliminary to genetic analysis, may represent a rapid, effective, and low-cost tool for the traceability and quality evaluation of chestnuts from different species and hybrids with no information on their origin. Full article

The inner shell of the chestnut (Castanea crenata) has long been used in Asia as a medicinal herb for improving digestion and blood circulation, and treating diarrhea. However, most chestnut shells are now treated as waste materials in industrial peeling processes. In this study, we examined the metabolite variation among major cultivars of C. crenata shells using mass spectrometry. Among five representative cultivars, Okkwang, Porotan, and Ishizuuchi had higher levels of bioactive compounds, such as ellagic acid derivatives, ellagitannins, flavonoids, and gallic acid derivatives. Their antioxidant capacity was positively correlated with their chemical composition. The byproducts (whole shells) from the industrial peeling process were re-evaluated in comparison with the inner shell, a rich source of phenolic compounds. The phenolic acids and flavonoid glucoside derivatives were significantly higher in the whole shells, whereas the levels of flavonoids were higher in the inner shells. In addition, the whole shell extracts significantly reduced cellular reactive oxygen species production compared to the inner shell extracts. This study demonstrated the different biochemical benefits of different C. crenata cultivars through metabolic profiling and suggests that the whole shell could be used as a functional ingredient, as it has the highest levels of bioactive products and antioxidant effects. Full article

Chestnuts are an important food crop commonly used as a food ingredient due to their nutritional properties and potential health benefits. In Korea, chestnuts have been crossbred to develop cultivars with insect resistance and high productivity, producing multiple chestnut varieties. This study classified 17 Castanea crenata cultivars produced in Korea according to origin and harvest time and determined the metabolites in chestnut kernels using ¹H nuclear magnetic resonance spectroscopy. The 17 C. crenata cultivars were divided into four groups based on their geographic origin: Korean native, Korean hybrid, Japanese native, and Japanese hybrid. The cultivars were also divided into three groups depending on their harvest period: early-ripening cultivar, mid-ripening cultivar, and late-ripening cultivar. The partial least squares-discriminant analysis score plot revealed differences among the groups. Identified metabolites, including amino acids, organic acids, and sugars, contributed to discriminating the origin and harvest time of the C. crenata chestnut kernels. Significant differences were observed, mainly in amino acids, which suggests that the composition of amino acids is one factor influenced by both the origin and harvest time of C. crenata. These results are useful to both growers and breeders because they identify the nutritional and metabolic characteristics of each C. crenata cultivar. Full article

Pollination is essential for efficient reproduction in pollinator-dependent crops that rely on the attraction of pollinators to flowers. Especially, floral nectar is considered to be an important factor attracting pollinator like honey bees, but differences among major chestnut species (Castanea crenata, C. mollissima, C. dentata, and C. sativa) are still little explored. This study aims to evaluate the value of honey source by analyzing floral nectar characteristics and comparing the composition of volatile organic compounds (VOCs) that mediate plant-pollinator interaction. In this study, we analyzed nectar samples obtained from male flowers using HPLC and HS-SPME/GC–MS. The five chestnuts showed significant differences between the volume of secreted nectar, free sugar composition, amino acid content and VOCs composition. Furthermore, C. crenata (Japanese cultivar ‘Ungi’) was revealed to emit the highest total amounts of VOCs and high levels of benzenoid compounds that are generally associated with flower-visiting insects. The sugar content per catkin, which is used to determine the honey yield, was the highest in C. crenata, suggesting that C. crenata ‘Ungi’ can be highly valued as a honey tree. Therefore, a better understanding of the relationship between pollinator and nectar characteristics of C. crenara could contribute to a prospective honey plant. Full article

Castanea sativa is an important multipurpose species in Europe for nut and timber production as well as for its role in the landscape and in the forest ecosystem. This species has low tolerance to chestnut gall wasp (Dryocosmus kuriphilus Yasumatsu), which is a pest that was accidentally introduced into Europe in early 2000 and devastated forest and orchard trees. Resistance to the gall wasp was found in the hybrid cultivar ‘Bouche de Bétizac’ (C. sativa × C. crenata) and studied by developing genetic linkage maps using a population derived from a cross between ‘Bouche de Bétizac’ and the susceptible cultivar ‘Madonna’ (C. sativa). The high-density genetic maps were constructed using double-digest restriction site-associated DNA-seq and simple sequence repeat markers. The map of ‘Bouche de Bétizac’ consisted of 1459 loci and spanned 809.6 cM; the map of ‘Madonna’ consisted of 1089 loci and spanned 753.3 cM. In both maps, 12 linkage groups were identified. A single major QTL was recognized on the ‘Bouche de Bétizac’ map, explaining up to 67–69% of the phenotypic variance of the resistance trait (Rdk1). The Rdk1 quantitative trait loci (QTL) region included 11 scaffolds and two candidate genes putatively involved in the resistance response were identified. This study will contribute to C. sativa breeding programs and to the study of Rdk1 genes. Full article