Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains

Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine environments.To answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern China.We also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen deposition.Stigmatic pollen deposition was more variable in distylous species than in homostylous species.Although seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous self-pollination.Our findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity.

The beneficial effects of Tartary buckwheat (Fagopyrum tataricum Gaertn.) on diet-induced obesity in mice are related to the modulation of gut microbiota composition

The gut is home to a large number of intestinal microbiota that play an important role in the metabolism and immune system of the host.A growing body of evidence suggests that a high-fat diet is closely associated with many metabolic disorders,including fatty liver and type 2 diabetes.According to reports,Tartary buckwheat extract has a positive effect on intestinal microbiota in animals.The effects of Tartary buckwheat on biochemical indexes and intestinal microflora in mice were studied.Tartary buckwheat protein(FGP),Tartary buckwheat resistant starch(FGS)and Tartary buckwheat flour(FGF)alleviated organ damage in mice and lowered the atherosclerotic index(AI)in plasma.Otherwise,principal coordinate analysis(PCoA)showed that intestinal bacterial structure of FGF were separated apparently from other groups.The Firmicutes/Bacteroidetes(F/B)value of the high-fat(HF)-FGF group was significantly lower than that of the HF-FGP and HF-FGS groups.FGF significantly increases the abundance of beneficial bacteria such as Bifidobacterium,while decreasing the abundance of lipopolysaccharide(LPS)-producing bacteria.Observation of blood lipid metabolism parameters and analysis of the intestinal microbiota suggested that FGF can be more effective than FGP and FGS to reduce the effects of a high-fat diet in mice,restoring the blood parameters to values similar of those in mice fed a low-fat diet.FGF may be used to prevent or treat blood lipid metabolism disorders and intestinal microbiota disorders in mice fed a high-fat diet.

Comparative study of the effects of Tartary buckwheat seed and sprout consumption on the physiological indices and gut microbiota of C57BL/6J mice

Tartary buckwheat(Fagopyrum tataricum)is a well-known pseudocereal for its health and economic value.However,abundant antinutritional factors(ANFs)reduces its health benefits.As reported,germination can improve the nutritional profile of grains.In this study,we systematically evaluate the safety of Tartary buckwheat seeds(TB)and Tartary buckwheat sprouts(TBS)used as high active ingredients.After evaluating nutrition levels,bioactive compounds and ANFs in TBS during germinating,5^(th)-day TBS were selected as the raw material.C57BL/6J mice were gavaged daily with distilled water,TB,or TBS for 6 weeks.The physiological indices related to ANFs were determined.Results showed that the TB intake tends to generate negative effects on the gut microbiota,and organs.Additionally,upon TB intake,the Fe^(3+)content in serum,trypsin activity in pancreas and jejunum decreased,while the cytokine,IgE,and histamine levels in serum,water content in faeces,cytokine levels in liver and jejunum increased.Conversely,TBS did not induce any obvious negative effects on the above relevant indices and showed better lipid-lowering effect.Altogether,TBS are safer and more effective as a raw material to produce the functional food for long-term consumption with the intention of preventing and treating hyperlipidaemia.

Preparation of Tartary Buckwheat Seed Coating Agent and Its Effect on Germination

To mitigate the wastage of seed resources and reduce the usage of pesticides and fertilizers, seed coating agentshave gained popularity. This study employs single-factor and multi-index orthogonal experimental design methodsto investigate the seed coating formula and physical properties of Tartary buckwheat. The specific effects ofeach component on Tartary buckwheat seed germination are analyzed. The findings reveal that the seed coatingagent formulated with 1.5% polyvinyl alcohol, 0.15% sodium alginate, 0.2% op-10, 0.1% polyacrylamide, 8% colorant,3% ammonium sulfate, 1% potassium dihydrogen phosphate, and 0.15% carbendazim exhibits the mosteffective coating. It demonstrates optimal physical properties and promotes seed germination efficiently. The suspensionrate of this seed coating agent reaches 91.12%, with a mere 2.13% coating shedding rate and 2.5% coatingseed rot rate. Furthermore, it achieves a germination percentage of 99.17%, which is 20.84% higher than the lowestgroup. The germination potential and index are also significantly higher than the lowest group, with anincrease of 20.84% and 26.56%, respectively. Additionally, the vitality index is 553.08, a 15.75% increase comparedto the lowest group. The application of seed coating agents helps reduce seed resource loss, increase plant numbers,and ultimately enhance agricultural yields. This finding holds practical significance in agriculturalproduction.

Silicon Mitigates Aluminum Toxicity of Tartary Buckwheat by Regulating Antioxidant Systems

Aluminum (Al) toxicity is a considerable factor limiting crop yield and biomass in acidic soil. Tartary buckwheatgrowing in acidic soil may suffer from Al poisoning. Here, we investigated the influence of Al stress on the growthof tartary buckwheat seedling roots, and the alleviation of Al stress by silicon (Si), as has been demonstrated inmany crops. Under Al stress, root growth (total root length, primary root length, root tips, root surface area, androot volume) was significantly inhibited, and Al and malondialdehyde (MDA) accumulated in the root tips. At thesame time, catalase (CAT) and ascorbate peroxidase activities, polyphenols, flavonoids, and 1,1-diphenyl-2-picrylhydrazyl(DPPH) and 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free-radical scavenging abilitywere significantly decreased. After the application of Si, root growth, Al accumulation, and oxidative damage wereimproved. Compared to Al-treated seedlings, the contents of ·O2− and MDA decreased by 29.39% and 25.22%,respectively. This was associated with Si-induced increases in peroxidase and CAT enzyme activity, flavonoidcompounds, and free-radical scavenging (DPPH and ABTS). The application of Si therefore has positive effectson Al toxicity in tartary buckwheat roots by reducing Al accumulation in the roots and maintaining oxidationhomeostasis.

Study on Germplasm Resources of Tartary Buckwheat (Fagopyrum tataricum) in Shanxi Province

This study analyzed the tartary buckwheat recorded in the books Catalogue of Crop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources by Excel 2003 and DPS 7.5 from the aspects of distribution areas,main agronomic traits and nutritional components,so as to lay a foundation for the selection of excellent buckwheat germplasm resources and improvement of buckwheat varieties.The results showed that different buckwheat varieties vary in plant height,node number of the main stem,grain weight per plant,grain weight per plant and kilo-grain weight.Compared with the national average values,buckwheat in Shanxi is higher in protein and fat,but lower in vitamin E and vitamin PP;it is rich in Ca,Mg,Cu,P,Se,Fe,Mn and Zn;and it contains 18 amino acids with the content of glutamic acid being the highest and the content of tryptophane being the lowest.After analyzing and classifying the tartary buckwheat germplasm resources recorded in Catalogue of Grop Germplasm Resources in Shanxi Province and Catalogue of Chinese Buckwheat Germplasm Resources,breeders could breed new varieties with high yield and quality and strong stress resistance by crossbreeding with these germplasm resources.

Effects of Different-concentration EMS on Germination of Tarary Buckwheat [Fagopyrum tataricum(L.) Gaertn] Seeds

[Objective] This study aimed to determine the optimum ethyl methane sulfonate（EMS） concentration for germination of tarary buckwheat seeds so as to lay a solid foundation for obtaining excellent traits of tarary buckwheat and breeding new varieties that meet the requirements by EMS mutation breeding. [Method] The seeds of Jinqiaomai No.4, a local tarary buckwheat variety [Fagopyrum tataricum（L.） Gaertn] in Shanxi Province, were used as the material. They were mutagenized by different concentrations（0.3%, 0.5%, 0.7%, 1.0%, 1.5%, 1.7%） of EMS for different times（4, 8, 12 h）. Then the germination rate and germination vigor were analyzed. [Result] With the increase of EMS mutagenic agent concentration, the germination vigor, relative germination vigor, germination rate and relative germination rate are all trended to be decreased. When the EMS concentrations ranged from 0.3%to 1.0%, there were no significant differences between treatment and control groups（P〉0.05）. When the EMS concentrations were 1.5% and 1.7%, significant differences were shown between treatment and control groups（P〈0.01）. The 4 and 8 h treatment of EMS all had no significant effects on germination rate and relative germination rate of Jinqiaomai No.4, but the 12 h treatment of EMS showed significant effects. Among the three treatment times, there were still no significant differences in germination vigor and relative germination vigor between treatment and control groups. [Conclusion] The optimum median lethal dose and treatment time of EMS for mutagenizing Jinqiaomai No.4 were 1.7% and 12 h, respectively.

Phenolic Profiles and Antioxidant Activity of Buckwheat (Fagopyrum esculentum Mench and Fagopyrum tartaricum L. Gaerth) Hulls, Brans and Flours

The extracts from hulls, brans and flours of Fagopyrum esculentum M6ench （FEM, three varieties） and Fagopyrum tartaricum L. Gaerth （FTG, seven varieties） were screened for free and bound phenolic content or total phenolic content （TPC）, as well as 1,1 diphenyl-2-picryl hydrazyl （DPPH） free radical scavenging activity and reducing power. Free phenolics were predominant in buckwheat hulls, brans and flours. FEM hulls extract exhibited the highest reducing power and DPPH free radical scavenging activity with the average ECs0 84.54 μg mL^-1 and IC50 11.54 μg mL^-1 respectively, FTG brans extract had the highest average TPC （24.87 mg GAE g^-1 DW）, and FEM flours extract showed the lowest TPC, reducing power and radical scavenging activity. Furthermore, the correlations among TPC, DPPH free radical scavenging activity and reducing power of all the samples were investigated. The rank correlation coefficient （rs） between reducing power and DPPH free radical scavenging activity of buckwheat hulls, between TPC and DPPH free radical scavenging activity of buckwheat flours were 0.76 and 0.79, respectively （P〈0.05）. However, there is no significant correlation between the remaining indexes of hulls and flours, as well as the ten buckwheat brans. This result indicated that some non-phenolic compounds also contributed to the total antioxidant activity in hulls, brans and flours of buckwheats. This study demonstrated that buckwheat hulls and brans, rather than flours, are good source of antioxidants.

Effects of Heat Treatment on Flavonoids Content and Antioxidant Capacity of Buckwheat (Fagopyrum tataricum Gaert) Flour Ethanolic Extracts

The chemical composition, total flavonoids and antioxidant capacity of 50% ethanolic extracts from raw and cooked buckwheat flour from southwest of China were determined. The heat treatment used to gelatinize the flour starch significantly reduced the total flavonoids in the extract from 83.52 to 67.36 mg 100 g 1 of dry matter in the raw and cooked flour, respectively. The antioxidant capacity of the extracts was evaluated using autooxidation in a β carotene linoleate model system (AA or AAC), DPPH radical scavenging assay (IP) and oxygen radical absorbance capacity (ORAC) assay. Values for raw buckwheat flour extract were 97.84, 874.31, 76.45 and 94.92% for AA, AAC, ORAC and IP, respectively, while values in cooked buckwheat flour were 86.14, 842.88, 63.93 and 94.74% for AA, AAC, ORAC and IP, respectively. Values before cooked and raw buckwheat flour extracts were significantly different ( P <0.05) for AA, AAC, and ORAC.

Plastome and phylogenetic relationship of the woody buckwheat Fagopyrum tibeticum in the Qinghai-Tibet Plateau

The phylogenetic position of the monotypic woody Parapteropyrum(Polygonaceae)remains controversial.Parapteropyrum has been thought to be closely related to the woody genera of the tribe Atraphaxideae,although some evidence indicates that it nests within the herbal buckwheat genus Fagopyrum of tribe Polygoneae.In this study,we used plastome data to determine the phylogenetic position of Parapteropyrum(Fagopyrum)tibeticum.Different reference species were used to assemble plastomes of three species currently placed in the tribe Ataphaxideae:Parapteropyrum(Fagopyrum)tibeticum,Atraphaxis bracteata and Calligonum ebinuricum.Once assembled,plastomes were characterized and compared to plastomes of 12 species across the family Polygonaceae.Phylogenetic analyses of Polygonaceae were performed using whole plastome,all plastome genes,and single-copy genes.Plastomes assembled using different reference plastomes did not differ;however,annotations showed small variation.Plastomes of Parapteropyrum(Fagopyrum)tibeticum,A.bracteata and C.ebinuricum have the typical quadripartite structure with lengths between 159,265 bp and 164,270 bp,and a total number of plastome genes of about 130.Plastome microsatellites(SSR)ranged in number from 48 to 77.Maximum Likelihood and Bayesian analyses of three plastome data sets consistently nested Parapteropyrum within the genus Fagopyrum.Furthermore,our analyses indicated that sampled woody genera of the family Polygonaceae are polyphyletic.Our study provides strong evidence that the woody Parapteropyrum tibeticum,which is distantly related to woody genera sampled here,should be taxonomically placed under Fagopyrum as Fagopyrum tibeticum.

Physiological and Biochemical Mechanisms of Exogenous Calcium Chloride on Alleviating Salt Stress in Two Tartary Buckwheat(Fagopyrum tataricum)Varieties Differing in Salinity Tolerance

Salt stress is one of the most serious abiotic stresses limiting plant growth and development.Calcium as an essential nutrient element and important signaling molecule plays an important role in ameliorating the adverse effect of salinity on plants.This study aimed to investigate the impact of exogenous calcium on improving salt tolerance in Tartary buckwheat cultivars,cv.Xinong9920(salt-tolerant)and cv.Xinong9909(salt-sensitive).Four-week-old Tartary buckwheat seedlings under 100 mM NaCl stress were treated with and without exogenous calcium chloride(CaCl_(2)),Ca^(2+)chelator ethylene glycol tetraacetic acid(EGTA)and Ca^(2+)-channel blocker lanthanum chloride(LaCl_(3))for 10 days.Then,some important physiological and biochemical indexes were determined.The results showed that salt stress significantly reduced seedling growth,decreased photosynthetic pigments,inhibited antioxidants and antioxidant enzyme activities.However,it increased the reactive oxygen species(ROS)levels in the two Tartary buckwheat cultivars.Exogenous 10 mM CaCl_(2)application on salt-stressed Tartary buckwheat seedlings obviously mitigated the negative effects of NaCl stress and partially restored seedlings growth.Ca^(2+)-treated salt-stressed seedlings diplayed a suppressed accumulation of ROS,increased the contents of total chlorophyll,soluble protein,proline and antioxidants,and elevated the activities of antioxidant enzymes compared with salt stress alone.On the contrary,the addition of 0.5 mM LaCl_(3)and 5 mM EGTA on salt-stressed Tartary buckwheat seedlings exhibited the opposite effects to those with CaCl_(2)treatment.These results indicate that exogenous Ca^(2+)can enhance salt stress tolerance and Ca^(2+)supplementation may be an effective practice to cultivate Tartary buckwheat in saline soils.

Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn)protein-derived antioxidant peptides:mechanisms of action and structure-activity relationship in Caco-2 cell models

Excessive reactive oxygen species(ROS)can cause oxidative damage and lead to various metabolic disease.Tartary buckwheat(Fagopyrum tataricum(L.)Gaertn)is a new kind of protein-rich functional food,the protein in which has been proved to have good antioxidant capacity.In this study,in order to further explore the antioxidant mechanism of Tartary buckwheat protein,4 peptides(CR-8,LR-8,GK-10 and SR-12)were isolated and identified from it.H2 O2 was used to induce oxidative damage to Caco-2 cells to evaluate antioxidant capacity of these peptides.The results of superoxide dismutase(SOD),total antioxidant capacity(T-AOC)and mitochondrial membrane potential etc.showed that these peptides have superior antioxidant capacity.CR-8 has the best antioxidant capacity.In order to further clarify the antioxidant mechanism of CR-8,metabolomics was used to analyze related metabolites and metabolic pathways.The results showed that after CR-8 intervention,the content of metabolites such as L-acetyl carnitine has increased.This indicated that CR-8 can improve the antioxidant capacity of damaged cells by intervening in multiple metabolic pathways.This also revealed the anti-oxidant mechanism of tartary buckwheat protein.In conclusion,it provided a theoretical basis for further studying the activity of tartary buckwheat portein and utilizing buckwheat resources.

Performance of common buckwheat(Fagopyrum esculentum M.) supplied with selenite or selenate for selenium biofortification in northeastern China

Selenium(Se)deficiency commonly occurs in soils of northeastern China and leads to insufficient Se intake by humans.A two-year field study of Se biofortification of common buckwheat supplied with 40 g Se ha^(-1)as selenite(Se(IV)),selenate(Se(VI)),or a combination(1/2 Se(IV+VI))was performed to investigate Se accumulation and translocation in plants and determine the effects of different forms of Se on the grain yield,biomass production,and Se use efficiency of plants and seeds.Se application increased seed Se concentrations to 47.1–265.1μg kg^(-1).Seed Se concentrations following Se(VI)or 1/2 Se(IV+VI)treatment exceeded 100μg kg^(-1),an amount suitable for crop Se biofortification.Se concentration in shoots and roots decreased with plant development,and Se translocation from root to shoot in Se(IV)-treated plants was lower than that in plants treated with 1/2 Se(IV+VI)and Se(VI).Both grain yield and biomass production increased under 1/2 Se(IV+VI)treatment,with grain yields reaching 1663.8 and 1558.5 kg ha^(-1)in 2015 and 2016,respectively,reflecting increases of 11.0% and 10.3% over those without Se application.The Se use efficiency of seeds and plants under Se(VI)treatment was significantly higher than those under 1/2 Se(IV+VI)and Se(IV)treatments.Thus,application of selenate could result in higher Se accumulation in buckwheat seeds than application of the other Se sources,but the combined application of selenate and selenite might be an alternative approach for improving buckwheat grain yield by Se biofortification in northeastern China.

GC-MS Analysis of Metabolites in Filling Grains of Rice-Tartary Buckwheat (Fagopyrum tataricum) in Comparison to Conventional Tartary Buckwheat

Rice-Tartary buckwheat(RTB)is a special germplasm of Tartary buckwheat.In this study,the appraisal of taste quality between RTB and conventional Tartary buckwheat(CTB)was presented,and the metabolites in kernels at three typical grain filling stage(GFS)were investigated.Unlike CTB,RTB showed thin shell seeds without longitudinal furrows at maturity,which was easily artificially dehulled.Sense organ test indicated that RTB exhibited better taste quality because of the higher values of appearance,viscosity,taste and summary were appraised.In total,92 metabolites were identified in kernels using GM-MS metabolomics platform.The levels of most metabolites changed greatly during grain filling and a large numbers of metabolite-metabolite correlations were found by Pearson correlation coefficient analysis.ANOVA analysis identified 61 differentially expressed metabolites between RTB and CTB,while Venn diagram analysis screened 35 common differential metabolites.Compared with CTB,RTB showed similar levels of lysine and methionine,indicated that RTB own excellent nutritional value.Additionally,RTB exhibited significantly up-regulated levels of most sweeteners(sugars and polyols),which might contribute to better taste.This work provides the first comprehensive metabolomics analysis of kernels between RTB and CTB,which may potentially provide theoretical basis for further research.

Effect of Planting Density on Physiological Indexes, Agronomic Traits and Yield of Buckwheat ( Fagopyrum esculentum Moench.)

Ningqiao 1 was selected as the material to study the effects of planting density on physiological indices,agronomic traits and yield of buckwheat.The results showed that high density resulted in decreases of chlorophyll content,soluble protein content and activity of SOD,POD and CAT,and acceleration of MDA accumulation under drought conditions.Low density could effectively improve the grain number per plant,grain weight per plant,1000-grain weight and yield in drought conditions.

Effects of nitrogen fertilizer on protein synthesis, accumulation, and physicochemical properties in common buckwheat

Nitrogen(N)fertilization affects grain quality in common buckwheat(Fagopyrum esculentum Moench).But the effects of N fertilizer on various buckwheat protein parameters are not fully understood.This study aimed to investigate the synthesis,accumulation,and quality of buckwheat protein under four N application rates in the Loess Plateau,China.Optimal N application(180 kg N ha-1)improved yield,agronomic traits,and N transport and increased protein yield and protein component accumulation.Prolamin and glutelin accumulation first increased and then decreased with increasing N application.The relationships between the contents of protein components and the amount of applied N generally followed quadratic functions.Nitrate reductase and glutamine synthetase activities first increased and then decreased with increasing N levels.Optimal N fertilizer increased the waterholding capacity and thermal stability of buckwheat protein and reduced its emulsification capacity,but negligibly changed its oil-absorption capacity.Hydrophobic amino acids and glutelin content were the main factors affecting protein quality.

Do Aqueous Extracts from Buckwheat Compromise Seed Germination and Initial Development of Bidens pilosa and Euphorbia heterophylla?

Fagopyrum esculentum Moench (buckwheat) is a dicot species from the Polygonaceae family used as a cover crop in agricultural systems featured with a remarkable allelopathic potential for weed control, helping herbicide-resistance management and promoting substantial reductions in herbicide applications. The aim of this research was to examine the allelopathic potential of aqueous extracts from seeds and aerial part of buckwheat on seed germination and initial development of Bidens pilosa and Euphorbia heterophylla. Bioassay experiments were conducted under a completely randomized experimental design with four replications, containing 50 seeds each. Both weed seed species were harvested in a soybean field, and seed viability was previously assessed. Seeds were exposed to four concentrations (0, 25, 50, and 100%) from extracts of seeds (ES) and aerial part (EAP) of buckwheat. Germination speed index (GSI) in B. pilosa and E. heterophylla was daily evaluated throughout 14 and 16 days, respectively, whereas percentage of germination, abnormal seedlings, as well as non-germinated seeds, root (RL) and aerial part length (APL), and total dry matter (TDM) were rated at final germination test. EAP reduced the GSI, especially under the 100% concentration. Germination percentage was lower and abnormal seedlings increased for both weed species when seeds were exposed to EAP concentrations greater than 25%. However, ES did not impinge upon E. heterophylla germination. EAP and ES reduced the APL, RL, and TDM for concentrations greater than 50%, except for ES which did not affect E. heterophylla development. Both extracts from buckwheat have a high capacity to inhibit germination and compromise seedling development, culminating in such a potential alternative for B. pilosa and E. heterophylla management in agricultural systems.

Seed Setting and Its Spatial Characteristics in Tartary Buckwheat(Fagopyrum tataricum)

A low seed-setting rate is the main limiting factor influencing Tartary buckwheat production under high-yield cultivation conditions.To investigate the seed setting and its spatial characteristics,two Tartary buckwheat cultivars(high seed-setting rate cultivar Qianku 3;low seed-setting rate cultivar Liuku 3)were compared by a two-year field trial in 2017 and 2018.The results showed that the Tartary buckwheat underwent simultaneous flowering and fruiting.Flowers,generated from branch,were still blooming during the mature stage of grains on stem,which resulting in a greater number of flowers and grains on the branch than those on the stem at the low part of plant.The seed-setting characteristics significantly differed between two cultivars.The high seed-setting rate of Qianku 3 was 26.6%and 33.2%higher than Liuku 3 in 2017 and 2018,respectively.Meanwhile,Qianku 3 showed a higher filled grain number(157.8%)and seed-setting rate(66.4%)on branch than Liuku 3.A network analysis showed that the whole-plant seed-setting rate was positively correlated with grain number,which was closely correlated with flower number at the same position of plant.The path-coefficient analysis revealed that grains number on branches was the most dominant component(Path coefficient(P)=2.19)of the seed-setting rate,followed by grains number on stem(P=0.60).The grains number on branches showed the greatest positive direct effect with significant correlation(r=0.76 and P<0.01)on the seed-setting rate.Overall,the present study indicated that the grain number of branches may play a vital role in improving the seed-setting rate in Tartary buckwheat.

Evaluation of the Mutagenicity Potential of Trace-Rutinosidase Variety of Tartary Buckwheat (Fagopyrum tataricum Gaertn.) Using the Ames Test

To ensure the safety of “Manten-Kirari”, a non-bitter and trace-rutinosidase variety of Tartary buckwheat, we evaluated its mutagenic activity in a bacterial reverse mutagenicity assay, the Ames test. Salmonella typhimurium TA100, TA1535, TA98, TA153, and Escherichia coli WP2 uvrA were employed as test bacteria. The flour of “Manten-Kirari” was dissolved at 12 - 50,000 μg/mL in DMSO and investigated. The number of revertants did not differ compared to the negative control for all concentrations tested, whereas that in the positive control, the number of revertants was increased with or without metabolic activation for each bacterial strain tested. These results suggested that the flour of the Tartary buckwheat “Manten-Kirari” was not genotoxic.

Comparative Analysis of the Transcriptome and Metabolome in Leaves of Diploid and Tetraploid Fagopyrum tataricum

Tartary buckwheat(Fagopyrum tataricum)is a dual-purpose medicinal and food crop grown for its high contents of functional compounds and abundant nutrients.Although studies have shown the differences of total flavonoid content in Tartary buckwheat at different ploidy levels,the composition of flavonoid and its regulatory mechanisms are largely unknown.In this study,the leaf metabolome and transcriptome of diploid and tetraploid accessions of Tartary buckwheat were analyzed to gain insight into the impact of polyploidization on comparative secondary metabolite composition and molecular regulatory mechanism.Based on a widely targeted metabolomics analysis,a total of 792 metabolites were identified,including 127 flavonoids.The accumulation of 127 metabolites and expression of 3871 genes differed significantly between diploid and tetraploid Tartary buckwheat.Integrated metabolomics and transcriptome analysis revealed that chromosome doubling up-regulated the expression of upstream genes in the flavonoid biosynthesis pathway to promote the accumulation of flavonoids.The present results contribute to elucidation of the molecular mechanism of phenotypic variation associated with polyploidy in Tartary buckwheat.The findings provide a reference for further studies on phenotypic traits in polyploid Tartary buckwheat,the cloning of crucial regulatory genes,and utilization of genetic engineering technologies in the breeding of Tartary buckwheat.