Aluminum toxicity (Al) is one of the main constraints for plant growth on acid soils. While most plants are sensitive to Al, some species have developed strategies to cope with this metal. Fagopyrum ...esculentum, Moench., var Mancan (Polygonaceae), despite being an aluminum-tolerant plant, shows root inhibition as a seedling during the first hours of exposure to Al, whereas at later times, it fully recovers. In this study, we assessed whether abscisic acid (ABA) levels and the antioxidant system might be involved in the early tolerance mechanisms of F. esculentum. The results showed that seedlings exposed to 50 μM Al for 3, 6, 12, 24, and 48 h showed decreases in the relative root growth (RRG), and there was an accumulation of Al in the root apex from 3 to 24 h. In addition, reactive oxygen species (ROS) levels increased, and were detected early after Al exposure; endogenous ABA levels increased and antioxidant enzyme activity increased, including catalase (CAT, EC1.11.1.6), glutathione reductase (GR, EC 1.6.4.2), ascorbate peroxidase (APX, EC 1.11.1.11), and superoxide dismutase (SOD, EC 1.15.1.1) activity. Seedlings treated with exogenous ABA also showed increased ROS levels and CAT and APX activity. The results suggest that after the first 12 h of Al treatment, root growth declines while ROS levels increase due to the entrance of Al into the root. However, the enzyme antioxidant system is promoted, which may impact the recovery of the root growth at later times and increasing levels of ABA might mediate this effect.
•Fagopyrum esculentum seedlings showed root growth inhibition and Al root accumulation during the first 12 h of Al exposure.•Once Al entered the cells, ROS formation was induced in a manner similar to when roots are treated with exogenous ABA.•Antioxidant enzyme activity increased in response to ROS formation at the root tips.•Endogenous ABA levels increased in response to Al and might be involved in promoting the antioxidant system.•The results suggest that ABA might play a role in regulating ROS homeostasis during Al toxicity.
Buckwheat freshness plays a key role in the qualities of noodles. The present study focuses on the protective effects of superheated steam (SS) processing on the quality deterioration of noodles made ...from stored buckwheat grains. Changes of the volatile compounds, lipid degrading enzymes, pasting properties, farinograph characteristics of buckwheat grains, together with the cooking qualities and texture profiles of buckwheat noodles were investigated. Results suggested that 3-methyl-butyraldehyde and hexanal were the markers of lipid oxidation and flavor change of buckwheat grains during storage. SS treatment inactivated lipase, lipoxygenase and peroxidase and affected the generation of off-flavor volatile compounds of buckwheat grains, thus retarded the flavor deterioration of buckwheat noodles made from stored buckwheat. Storage significantly (P < 0.05) decreased the pasting viscosities, water absorption and development time of buckwheat dough. SS treatment maintained the pasting properties of starch stable and enhanced the elasticity and strength of the dough, leading to the improvement of cooking qualities and texture profiles of buckwheat noodles. Therefore, SS processing was an effective way to improve the qualities of buckwheat noodles by stabilizing buckwheat grains.
•Hexanal and 3-methyl-butyraldehyde marked flavor change of buckwheat during storage.•Cooking and texture qualities of noodles made from stored buckwheat deteriorated.•Superheated steam inactivated lipase, lipoxygenase and peroxidase of buckwheat.•Superheated steam processing maintained the starch stable and enhanced dough strength.•Superheated steam treatment improved noodle qualities by stabilizing buckwheat grains.
Common buckwheat (Fagopyrum esculentum Moench), a dicotyledonous plant in family Polygonaceae, is recognized as a valuable nutritional source of fatty acids, phytosterols, phenolic compounds and ...tocopherols. It has received increased attention as a so-called "functional food" in China. During scouting of common buckwheat in August and September 2018, unfamiliar symptoms were observed on leaves in 20 fields in Yanchi County, Ningxia, China, with 35% incidence and moderate to high severity across the field. Brown spots most commonly occurred on lower leaves of buckwheat beginning in late July. The spots were initially light brown with an irregular border and pale brown center. Older spots were almost dark brown, and often coalesced although spots were restricted by veins. Symptomatic leaf samples were collected in late-August, and washed with flowing water for 2 min. Tissue samples were excised from the margins of the lesions and sterilized with 75% ethanol for 20 s and 0.1% NaClO for 2 min, before being rinsed with sterilized water four times, dried on sterile paper towels, and cultured on Potato Dextrose Agar medium at 20 °C. After 48 to 72 h, hyphae grew from tissue pieces. The obtained isolates were purified using the single-spore isolation technique. A total of thirteen isolates were recovered and characterized. Colonies of all isolates on PDA were identical, and were pale brown to brown, velvety, with irregular borders. Hyphae were hyaline to brown, branched, septate, smooth, sometimes verruculose, 3-7 μm wide. Conidiophores were (83-297) µm×(5.5-9) µm (avg. 205 µm×8 µm, n=30), dark brown, cylindrical, straight to slightly flexuous, geniculate at the upper end, septate, single, smooth. Conidia were rostrate, obclavate, straight to slightly curved, hyaline to pale brown when immature and brown to reddish brown when mature, and measured (38-104) µm×(11-19) µm (avg. 67 µm×16 µm, n=50). End cells were often paler than middle cells and with a thick dark hilum. Based on the cultural and morphological characteristic, these isolates are preliminary identified as Bipolaris zeae (Manamgoda et al., 2014; Sivanesan, 1985). Genomic DNA of the representative isolate qyj-5A was extracted and amplified using GAPDH primers (gpd 1/2) and ITS primers (ITS 1/4) respectively. The sequence of the amplicons was compared with reference sequences. The ITS sequence (GenBank: MT645704) showed 100% (571/571bp, 564/564bp) identity with B. zeae (GenBank: KU356179 and KU571464, respectively). The GAPDH sequence (GenBank: MW426530) also showed 100% (594/594bp) identity values with B. zeae (GenBank: MF415650 and KU571468). Pathogenicity tests were performed on three healthy and asymptomic buckwheat plants, which were surface sterilized with 75% ethanol and rinsed with sterilized distilled water. The leaves were sprayed with 1×105 conidia/ml of the suspensions which contain 0.01% Tween 20 and three control plants sprayed with same volume of sterile distilled water. A strip of parafilm was wrapped around the inoculated leaves for 48 h to maintain high relative humidity. At 6 days postinoculation, all the inoculated leaves showed symptoms identical to those described above. While no symptoms were observed on the control plants. The fungus was reisolated and identified as B. zeae based on morphological features and DNA sequence analysis, it was identical to the original isolate to satisfy Koch's postulates. B. zeae has been reported to be pathogenic on Acer truncatum (Sun et al., 2011), Helianthus tuberosus (Zhao et al., 2017) and Hemarthria altissima (Xue et al., 2016) in China. To our knowledge this is the first report of B. zeae causing leaf spot on F. esculentum in China. This fungal pathogen represents a severe threat and has the potential to cause yield losses of F. esculentum, so further research is required to define effective management strategies.
The localizations of sodium exclusion are roots and stem base, however, Na+ distribution in these localizations is unclear. Here, we used a salt-tolerant buckwheat cultivar Chuanqiao No.1 and a ...salt-sensitive cultivar TQ-0808 to demonstrate Na+ distribution. We found that Na+ content was highest in vacuole, the following was in cell wall or free space, and the least was in cytoplasm. Comparative analysis shows that Na+ accumulation in vacuole, cell wall, or free space of roots and stem base in 'Chuanqiao No.1' was obviously higher than in 'TQ-0808'; in contrast, Na+ accumulation in cytoplasm of 'Chuanqiao No.1' was less than in 'TQ-0808'. These results indicate that the capabilities of Na+ extrusion and Na+ compartmentalization of salt-tolerant buckwheat were obviously higher than of the salt-sensitive one, and the capabilities could effectively restrict Na+ transport to shoot. Compartmentalization of Na+ in the vacuole was the main way for Na+ exclusion of salt-tolerant buckwheat. In addition, the transcriptions of Na+/H+ antiporter 1 and salt overly sensitive 1 were remarkably higher in 'Chuanqiao No.1' than in 'TQ-0808', which is consistent with the above results.
Buckwheat is an important grain crop known for its nutritional value and content of bioactive compounds, particularly rutin. In this study, we characterized diverse
Fagopyrum esculentum
Moench ...germplasm for the diversity of agro-morphological characteristics and the rutin and quercetin content in seeds under the spring cultivation. Of the 251 germplasm accessions assessed, 193 had red stems, 182 had a pale brown seed coat color, and 238 had ovate seeds. The times taken to reach 50% flowering and 80% maturity ranged from 38–45 to 73–95 days, respectively. The 1000-seed weight (TSW) varied from 21 to 42 g. Overall, the content of rutin and quercetin ranged from 7.22–47.86 to 0–1.22 mg/100 g DW, respectively. The number of days to flowering and maturity showed negative correlations with TSW and rutin and quercetin content. However, we found that at 73–80 days after sowing, early-maturing germplasm had significantly higher mean rutin content than either intermediate-or late-maturing germplasm. The TSW weight showed a positive correlation with the content of rutin and quercetin. We identified promising accessions based early maturity (< 80 days), higher seed weight (≥ 35 g) and higher content of rutin (≥ 35 mg/100 g DW) and quercetin (≥ 1 mg/100 g DW). These accessions will help to enhance grain yield and the rutin and quercetin content in existing buckwheat cultivars for spring cultivation.
With the aim to provide valuable insight into the experimental conditions which significantly influence extraction efficiency of the specific bioactive components from the common buckwheat aerial ...parts, Box–Behnken method was employed to design experiments that were performed using maceration at a room temperature. The effects of three process variables, ethanol (EtOH) concentration, extraction time and hydroxypropyl-β-cyclodextrin (HP-β-CD) concentration, were evaluated using response surface methodology (RSM) and artificial neural network (ANN). Obtained results revealed superior accuracy of the created ANN model over the traditional RSM, with the suggested optimal conditions: 40% EtOH concentration, 4% HP-β-CD concentration and 72 h extraction time. HP-β-CD encapsulation significantly enhanced the stability of rutin and quercetin in the optimal extract after exposure to stress conditions during the 30-day period. Additionally, Fourier-transform infrared spectroscopy (FT-IR) and molecular dynamics simulations were used for the structural characterization of the cyclodextrin inclusion complexes at the molecular level.
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•Different methods were used to optimize the process of buckwheat extraction.•Artificial Neural Network model showed superior accuracy over the traditional one.•EtOH and HP-β-CD concentrations had a positive impact on the extraction efficiency.•HP-β-CD complexation enhanced the stability of the extract under stress conditions.•FT-IR analysis and MD simulations revealed formation of the inclusion complexes.
Peristenus spretus feeding on buckwheat (Photo by Ting Geng).
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•Peristenus spretus is the dominant parasitoid of the mirid Apolygus lucorum in China.•Adult parasitoids feed on ...buckwheat nectar which enhances their survival and parasitism capacity.•Fructose, the most dominant sugar in the nectar, contributes greatest to parasitoid fitness.•Glucose is the second most abundant sugar also significantly improving the female lifespan and reproduction.
Supplementary nutrients such as floral nectar or sugars are important food sources for the fitness and reproduction of parasitic Hymenoptera. Peristenus spretus is the dominant parasitoid of the mirid bug Apolygus lucorum and can exert considerable control of this pest. Previous studies found that the addition of buckwheat (Fagopyrum esculentum) strips in cotton fields improved P. spretus parasitism of A. lucorum nymphs. In this study, we showed that buckwheat flowers prolonged parasitoid lifespan by 1.7- to 3-fold, depending on wasp sex, and increased the daily parasitism rate by 10.3% compared with the control treatment without flowers. Soluble sugars, primarily fructose, glucose, maltose, mannose, raffinose, and sucrose, accounted for 6.3% of nectar weight. Supplementation of the four most common sugars (fructose, glucose, mannose, and sucrose) all had positive effects on P. spretus lifespan and reproduction. Fructose was the most dominant sugar in buckwheat nectar and had the most significant impact on these variables, suggesting it is the most suitable sugar for P. spretus adults. Glucose was the second most abundant sugar in the nectar, and its supplements significantly extended female longevity and the number of progeny produced per female compared to controls. This study identifies the sugars in buckwheat nectar that enhance the survival and parasitic activity of P. spretus, providing insights to potentially enhance biological control of this mirid pest of cotton.
•Flowers of red-flowered common buckwheat had the highest total flavonoid content, followed by Tartary buckwheat flowers.•A total of 188 flavonoid metabolites were identified using UPLC–ESI–MS/MS in ...the present study.•There are distinct differences in the flavonoid metabolism between Tartary and common buckwheat flowers.•Both Tartary and common buckwheat flowers had unique functional flavonoid metabolites.
Flavonoids are the largest group of secondary metabolites, and they play important biological functions. Buckwheat, particularly its flowers, contains a considerable amount of flavonoids. However, only a few flavonoid metabolites have been identified to date, and differences in flavonoid metabolites between Tartary and common buckwheat flowers have not yet been reported. In the present study, one Tartary buckwheat variety with green flowers and three common buckwheat varieties with white, pink and red flowers were sampled. Flowers of red-flowered common buckwheat had the highest total flavonoid content, followed by Tartary buckwheat flowers. The flower extracts were analysed using ultra-performance liquid chromatography–electrospray ionisation–tandem mass spectrometry (UPLC–ESI–MS/MS), and a total of 188 flavonoid metabolites, including 53 flavones, 39 flavonols, 33 flavone C-glycosides, 24 flavanones, 18 anthocyanins, 11 isoflavones, 5 proanthocyanidins and 5 flavonolignans, were detected. Multivariate statistics revealed a distinct difference in the flavonoid metabolism between Tartary and common buckwheat flowers, and both of them had unique functional metabolites. For example, common buckwheat flowers were rich in luteolin and apigenin, whereas Tartary buckwheat flowers were rich in tricin. These results provide new information regarding the flavonoid metabolites of buckwheat flowers and offer important theoretical support for the exploitation of buckwheat flowers.
The pseudocereal buckwheat is one of the ancient domesticated crops. The aim of the present review was to outline the potential of buckwheat as an agricultural crop and brings studies on buckwheat ...into a new larger perspective combining current knowledge in agricultural history and practice, nutritional and sensory properties, as well as possible benefits to human health. Historically, buckwheat was an appreciated crop because of its short growth period, moderate requirements for growth conditions, and high adaptability to adverse environments. Nowadays, interest in buckwheat-based food has increased because of its nutritional composition and many beneficial properties for human health. Buckwheat is a rich course of proteins, dietary fibers, vitamins, minerals, and bioactive compounds, including flavonoids. Moreover, it contains no gluten and can be used in the production of gluten-free foods for individuals diagnosed with celiac disease, non-celiac gluten sensitivity, or wheat protein allergies. Buckwheat is traditionally used in the production of various foods and can be successfully incorporated into various new food formulations with positive effects on their nutritional value and attractive sensory properties. Further research is needed to optimize buckwheat-based food development and understand the mechanism of the health effects of buckwheat consumption on human well-being.
Introduction The sowing date plays a crucial role in influencing the growth and reproduction of plants, with its specific impact on biomass allocation and allometric growth remaining unclear. ...Understanding these effects is essential for optimizing agricultural practices and enhancing crop productivity. Methods To investigate the effects of sowing dates on biomass allocation and allometric growth, a field experiment was conducted with sequential sowings of Fagopyrum esculentum from April 12th to August 11th in 2018. Biomass measurements were taken across various plant organs, and corresponding allocation calculations were made. A detailed analysis of the allometric growth relationship involving organ biomass variations was performed. Results The study revealed that the accumulation and allocation of organ biomass in buckwheat were significantly impacted by the sowing dates. Delayed planting led to reduced vegetative growth and increased biomass allocation towards reproduction. Allometric parameters such as exponent, constant, and individual size of buckwheat were notably affected by delayed planting. Interestingly, the allometric exponents governing the relationships between reproductive vs. vegetative biomass and belowground vs. aboveground biomass exhibited varying trends across different sowing dates. Discussion Notably, late sowings resulted in significantly higher reproductive biomass compared to early and middle sowings. These findings highlight the nuanced relationship between plant size and reproductive biomass under different sowing dates, emphasizing the critical role of planting timing in shaping mature plant sizes and reproductive outcomes. The study underscores the importance of considering sowing dates in agricultural practices to optimize plant growth and productivity.
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