Quantitative predictions of protein and total flavonoids content in Tartary and common buckwheat using near-infrared spectroscopy and chemometrics.

A rapid method was developed for determining the total flavonoid and protein content in Tartary buckwheat by employing near-infrared spectroscopy (NIRS) and various machine learning algorithms, including partial least squares regression (PLSR), support vector regression (SVR), and backpropagation neural network (BPNN). The RAW-SPA-CV-SVR model exhibited superior predictive accuracy for both Tartary and common buckwheat, with a high coefficient of determination (R2p = 0.9811) and a root mean squared error of prediction (RMSEP = 0.1071) for flavonoids, outperforming both PLSR and BPNN models. Additionally, the MMN-SPA-PSO-SVR model demonstrated exceptional performance in predicting protein content (R2p = 0.9247, RMSEP = 0.3906), enhancing the effectiveness of the MMN preprocessing technique for preserving the original data distribution. These findings indicate that the proposed methodology could efficiently assess buckwheat adulteration analysis. It can also provide new insights for the development of a promising method for quantifying food adulteration and controlling food quality.

Development of an effective method for purifying trypsin using a recombinant inhibitor.

A trypsin affinity material was prepared by covalently immobilizing buckwheat trypsin inhibitor (BTI) on epichlorohydrin-activated cross-linked agarose gel (Selfinose CL 6 B). The optimal conditions for activating Selfinose CL 6 B were 15 % epichlorohydrin and 0.8 M NaOH at 40 °C for 2 h. The optimal pH for immobilizing BTI was 9.5. BTI-Sefinose CL 6 B showed a maximum adsorption capacity of 2.25 mg trypsin/(g support). The material also displayed good reusability, retaining over 90 % of its initial adsorption capacity after 30 cycles. High-purity trypsin was obtained from locust homogenate using BTI-Selfinose CL 6 B through one-step affinity chromatography. The molecular mass and Km value of locust trypsin were determined as 27 kDa and 0.241 mM using N-benzoyl-DL-arginine-nitroanilide as substrate. The optimal temperature and pH of trypsin activity were 55 °C and 9.0, respectively. The enzyme exhibited good stability in the temperature range of 30-50 °C and pH range of 4.0-10.0. BTI-Selfinose CL 6 B demonstrates potential application in the preparation of high-purity trypsin and the discovery of more novel trypsin from various species.

Role of cotyledons in aluminium accumulation as a tolerance strategy in Fagopyrum esculentum Moench (Polygonaceae) seedlings.

Acidic soils have increased due to agricultural practices, climate factors, and the excessive use of nitrogen fertilizers to meet food demand. In these soils, aluminium (Al) is soluble and can be taken up by roots, but it is toxic to most plant species. Fagopyrum esculentum is able to adapt to acidic toxic aluminium conditions. Anatomical studies identifying novel potential cellular structures as sites of Al accumulation are currently lacking. This study provides an anatomical description of the cotyledons, revealing the presence of papillae and glandular trichomes at their margins. In seedlings treated with 100 µM Al, energy-dispersive x-ray spectroscopy (ESEM-EDS) analysis of the cotyledons revealed that the margin has the highest concentration of Al. The margin containing the epidermal papillae was subjected to laser microdissection, and Al was quantified using mass spectrometry with an inductively coupled plasma source ICP-MS and compared with the Al in the remaining leaf blades. The concentration of Al in the microdissected papillae was 3,460 mg Al kg-1 Dry Weight (DW), whereas the blades contained only 1,390 mg Al kg-1 DW. Moreover, histochemical tests for Al and total phenols in the epidermal papillae revealed that Al may be bound to phenolic compounds. Thus, this study demonstrated that the cotyledons of F. esculentum have epidermal papillae that can accumulate Al.

The impact of buckwheat and paulownia (Paulownia elongata × P. fortunei) intercropping on beekeeping value and buckwheat yield.

Increasing crop diversity is a way for agriculture to transition towards a more sustainable and biodiversity-friendly system. Growing buckwheat intercropped with paulownia can contribute not only to mitigating climate change but can also enrich the environment with species of agricultural importance, without causing a decline in pollinators, since buckwheat is pollinated mainly by the honeybee. In a field experiment comparing growing buckwheat with paulownia against a monoculture crop, we investigated differences in flower visitation and beekeeping value, as well as the associated impact on crop yields. We analysed the effect of intercropping on the beekeeping value of buckwheat in terms of bee population size and the sugar mass in buckwheat flowers, nectar mass in buckwheat flowers, the quality of the delivered raw sugar and biometric characteristics. We found significant differences in the number of branches on the main shoot and the total number of branches. Significantly higher parameters were obtained in sites with buckwheat monoculture. The cultivation method variant did not cause differentiation in either the structure elements or the yield itself. Yields ranged from 0.39 (2021) to 1.59 (2023) t·ha-1. The average yield in intercropping was slightly lower (0.02 t·ha-1) than in the monoculture system of buckwheat (0.93 t·ha-1). More flowers per plant per day of observation and more flowers in millions of flowers per hectare per day of observation were observed in the intercropping of buckwheat with paulownia. Based on our experiment, we concluded that growing buckwheat in monoculture significantly increased the number of flowers, resulting in an increase in pollinator density and an increased number of pollinators per unit area.

QTL Mapping and Candidate Gene Analysis for Starch-Related Traits in Tartary Buckwheat (Fagopyrum tataricum (L.) Gaertn).

Starch is the main component that determines the yield and quality of Tartary buckwheat. As a quantitative trait, using quantitative trait locus (QTL) mapping to excavate genes associated with starch-related traits is crucial for understanding the genetic mechanisms involved in starch synthesis and molecular breeding of Tartary buckwheat varieties with high-quality starch. Employing a recombinant inbred line population as research material, this study used QTL mapping to investigate the amylose, amylopectin, and total starch contents across four distinct environments. The results identified a total of 20 QTLs spanning six chromosomes, which explained 4.07% to 14.41% of the phenotypic variation. One major QTL cluster containing three stable QTLs governing both amylose and amylopectin content, qClu-4-1, was identified and located in the physical interval of 39.85-43.34 Mbp on chromosome Ft4. Within this cluster, we predicted 239 candidate genes and analyzed their SNP/InDel mutations, expression patterns, and enriched KEGG pathways. Ultimately, five key candidate genes, namely FtPinG0004897100.01, FtPinG0002636200.01, FtPinG0009329200.01, FtPinG0007371600.01, and FtPinG0005109900.01, were highlighted, which are potentially involved in starch synthesis and regulation, paving the way for further investigative studies. This study, for the first time, utilized QTL mapping to detect major QTLs controlling amylose, amylopectin, and total starch contents in Tartary buckwheat. The QTLs and candidate genes would provide valuable insights into the genetic mechanisms underlying starch synthesis and improving starch-related traits of Tartary buckwheat.

Exogenous melatonin enhances the continuous cropping tolerance of Tartary buckwheat (Fagopyrum tataricum) by regulating the antioxidant defense system.

The yield of Tartary buckwheat is significantly affected by continuous cropping. Melatonin plays a crucial role in plant defense mechanisms against abiotic stresses. However, the relationship between melatonin and continuous cropping tolerance remains unclear. This study aimed to analyze the physiological mechanism of melatonin in enhancing the continuous cropping tolerance (abiotic stress) of Tartary buckwheat. A field experiment was conducted on Tartary buckwheat cultivar Jinqiao 2 under continuous cropping with five melatonin application rates, 0 (Control), 10, 50, 100, and 200 µmol L-1, applied during the early budding stage. The chlorophyll content, antioxidant enzyme activity, osmolyte and auxin (IAA) contents, root activity, rhizosphere soil nutrient content, and agronomic traits of Tartary buckwheat initially increased and then decreased with an increase in the concentration of exogenous melatonin application, with the best effects observed at 100 µmol L-1. Compared with the Control treatment, the 100 µmol L-1 treatment decreased the contents of malondialdehyde, superoxide anion free radical, and abscisic acid (ABA) by an average of 28.79%, 27.08%, and 31.64%, respectively. Exogenous melatonin treatment significantly increased the yield of Tartary buckwheat under continuous cropping. Plants treated with 10, 50, 100, and 200 µM respectively had 1.88, 2.01, 2.20, and 1.78 times higher yield than those of the Control treatment. In summary, melatonin treatment, particularly 100 µmol L-1, enhanced the continuous cropping tolerance of Tartary buckwheat by increasing antioxidant capacity and osmotica content, coordinating endogenous ABA and IAA content levels, and delaying senescence, ultimately increasing yield.

Novel mutations in acetolactate synthase confer high levels of resistance to tribenuron-methyl in Fagopyrum tataricum.

Tartary buckwheat (Fagopyrum tataricum) field weeds are rich in species, with many weeds causing reduced quality, yield, and crop failure. The selection of herbicide-resistant Tartary buckwheat varieties, while applying low-toxicity and efficient herbicides as a complementary weed control system, is one way to improve Tartary buckwheat yield and quality. Therefore, the development of herbicide-resistant varieties is important for the breeding of Tartary buckwheat. In this experiment, 50 mM ethyl methyl sulfonate solution was used to treat Tartary buckwheat seeds (M1) and then planted in the field. Harvested seeds (M2) were planted in the experiment field of Guizhou University, and when seedlings had 5-7 leaves, the seedlings were sprayed with 166 mg/L tribenuron-methyl (TBM). A total of 15 resistant plants were obtained, of which three were highly resistant. Using the homologous cloning method, an acetolactate synthase (ALS) gene encoding 547 amino acids was identified in Tartary buckwheat. A GTG (valine) to GGA (glycine) mutation (V409G) occurred at position 409 of the ALS gene in the high tribenuron-methyl resistant mutant sm113. The dm36 mutant harbored a double mutation, a deletion mutation at position 405, and a GTG (valine) to GGA (glycine) mutation (V411G) at position 411. The dm110 mutant underwent a double mutation: an ATG (methionine) to AGG (arginine) mutation (M333R) at position 333 and an insertion mutation at position 372. The synthesis of Chl a, Chl b, total Chl, and Car was significantly inhibited by TBM treatment. TBM was more efficient at suppressing the growth of wild-type plants than that of mutant plants. Antioxidant enzyme activities such as ascorbate peroxidase, peroxidase, and superoxide dismutase were significantly higher in resistant plants than in wild-type after spraying with TBM; malondialdehyde content was significantly lower than in wild-type plants after spraying with TBM. Plants with a single-site mutation in the ALS gene could survive, but their growth was affected by herbicide application. In contrast, plants with dual-site mutations in the ALS gene were not affected, indicating that plants with dual-site mutations in the ALS gene showed higher levels of resistance than plants with a single-site mutation in the ALS gene.

Efficiency of metal(loid) phytostabilization by white lupin (Lupinus albus L.), common vetch (Vicia sativa L.), and buckwheat (Fagopyrum esculentum Moench).

Erosion and leaching of metal(loid)s from contaminated sites can spread pollution to adjacent ecosystems and be a source of toxicity for living organisms. Phytostabilization consists of selecting plant species accumulating little or no metal(loid)s in aerial parts to establish a vegetation cover and thus to stabilize the contaminants in the soil. Seeds of white lupin, common vetch, and buckwheat were sown in greenhouse on soils from former French mines (Pontgibaud and Vaulry) contaminated with metal(loid)s including high concentrations of As and Pb (772 to 1064 and 121 to 12,340 mg kg-1, respectively). After 3 weeks of exposure, the growth of white lupin was less affected than that of the 2 other species probably because metal(loid) concentrations in roots and aerial parts of lupins were lower (5-20 times less Pb in lupin leaves on Pontgibaud soil and 5-10 times less As in lupin leaves on Vaulry soil than in vetch and buckwheat). To limit oxidation and/or scavenge metal(loid)s, white lupin increased the content of proline and total phenolic compounds (TPC) in leaves and roots by a factor 2 whereas buckwheat stimulated the production of TPC by a factor 1.5-2, and non-protein thiols (NPT) by factors around 1.75 in leaves and 6-12 in roots. Vetch accumulated more proline than white lupin but less NPT than buckwheat and less TPC than the 2 other plant species. The level of oxidation was however higher than in control plants for the 3 species indicating that defense mechanisms were not completely effective. Overall, our results showed that white lupin was the best species for phytostabilization but amendments should be tested to improve its tolerance to metal(loid)s.

Insights into the effect mechanism of freeze-thaw cycles on starch gel structure and quality characteristics of frozen extruded whole buckwheat noodles.

The effects of freeze-thaw cycles (FTC) on starch gel structure and quality characteristics of frozen extruded whole buckwheat noodles (FEWBN) were studied. The repeated FTC treatments induced the retrogradation of amylose which increased the compactness, crystallinity, hardness, and cooking time of FEWBN. However, with the increasing number of freeze-thaw cycles, the larger volume of ice crystals formed in the noodles destroyed the starch gel network structure to a certain extent, and led to the dehydration and syneresis of the noodles, and the quality deterioration. However, moderate amylose retrogradation occurred during the FTC treatment was found to be beneficial for the quality of FEWBN. After one time of FTC treatment, the cooking loss of 3.53 % was even lower compared with that without FTC treatment (4.61 %). After seven times of FTC treatment, the cooking loss of FEWBN was 6.53 %, and the breaking rate was still 0, indicating that FEWBN could resist the damage caused by temperature fluctuations on the internal structure of frozen food to a certain extent, and maintain good quality. This study establishes a fundamental basis for the development of buckwheat noodles with good freeze-thaw stability and high cooking quality.

The Complex FtBBX22 and FtHY5 Positively Regulates Light-Induced Anthocyanin Accumulation by Activating FtMYB42 in Tartary Buckwheat Sprouts.

Anthocyanin is one important nutrition composition in Tartary buckwheat (Fagopyrum tataricum) sprouts, a component missing in its seeds. Although anthocyanin biosynthesis requires light, the mechanism of light-induced anthocyanin accumulation in Tartary buckwheat is unclear. Here, comparative transcriptome analysis of Tartary buckwheat sprouts under light and dark treatments and biochemical approaches were performed to identify the roles of one B-box protein BBX22 and ELONGATED HYPOCOTYL 5 (HY5). The overexpression assay showed that FtHY5 and FtBBX22 could both promote anthocyanin synthesis in red-flower tobacco. Additionally, FtBBX22 associated with FtHY5 to form a complex that activates the transcription of MYB transcription factor genes FtMYB42 and FtDFR, leading to anthocyanin accumulation. These findings revealed the regulation mechanism of light-induced anthocyanin synthesis and provide excellent gene resources for breeding high-quality Tartary buckwheat.