FAGOPYRUM
Volume 37(1), May 2020
ISSN 0352 – 3020
Scientific Journal on Buckwheat Research
International Buckwheat Research Association
Slovenska akademija znanosti in umetnosti
Slovenian Academy of Sciences and Arts
FAGOPYRUM volume 37(1), May 2020
An international journal on buckwheat research published by The Slovenian Academy of Sciences and Arts,  
Ljubljana, Slovenia, under the auspices of The International  Buckwheat Research Association (IBRA).
Confirmed by the Class of Natural Sciences of the The Slovenian Academy of Sciences and Arts  on  
June 6, 2019 and the Presidency of the Academy on November 12, 2019. 
Managing Editorial Board
Ivan Kreft (Editor-in-Chief) (Slovenia)
Christian Zewen (Associate Editor) (Luxembourg)
Blanka Vombergar (Associate Editor) (Slovenia)
Mateja Germ (Associate Editor) (Slovenia)
Kiyokazu Ikeda (Associate Editor) (Japan)
Clayton Campbell (Language Editor) (Canada)
Advisory Board
Y. Asami, Ryukoko University, Ohtsu, Japan
T. Bjorkman, Cornell Univerity, Geneva, USA
C. Campbell, Chairperson of the 7thISB, Canada
N. K. Chrungoo, North Eastern University, Shillong, India
N. N. Fesenko, All-Russia Research Institute of Legumes and Groat Crops, Orel, Russia
M. Germ, University of Ljubljana, Ljubljana, Slovenia
H. Hayashi, Tsukuba University, Tsukuba, Japan
Y. Honda, National Agriculture and Food Research Organization, Tsukuba, Japan
S. Ikeda, Kobe Gakuin University, Kobe, Japan
N. Inoue, Shinshu University, Minami-Minowa, Japan
D. Janovska, Crop Research Institute, Praha, Czech
R. Lin, Shanxi Academy of Agricultural Science, Taiyuan, China
R. L. Obendorf, Cornell University, Ithaca, USA
O. Ohnishi, Kyoto University, Kyoto, Japan
R. Ohsawa, Tsukuba University, Tsukuba, Japan
C. H. Park, Kangwon National University, Chunchon, Korea
J. C. Rana, ICAR-National Bureau of Plant Genetic Resources, New Delhi, India
G. N. Suvorova, All-Russia Research Istitute on Legumes and Groat Crops, Orel, Russia
G. Wieslander, Department of Medical Sciences, Uppsala University and University Hospital, Uppsala, Sweden
S.-H. Woo, Chungbuk National University, Cheongju, Korea
Y. Yasui, Kyoto University, Kyoto, Japan
Editor Emeritus: Toshiko Matano, Ohmi Ohnishi, Kiyokazu Ikeda
Subscription Information: One volume per year: subscription price for printed issues 2018 is US $80.00 for  
individuals and scientific institutions. Authors, reviewers and editors of the issue receive free printed copies.
Electronic versions are untill further freely available for academic and non-commercial use at
http://www.sazu.si/publikacije-sazu 
FAGOPYRUM is open to everyone who is interested in buckwheat and will cover all aspects of buckwheat 
research: genetics, cytology, breeding, agronomy, nutrition, utilization, biochemistry, ethnobotany and others. 
FAGOPYRUM will accept manuscripts in English only, which meet the scientific requirements set by the Editorial 
Board and which have not been published or submitted for publication elsewhere. Announcements concerning 
the promotion of research on buckwheat (workshops, symposium and so on), bibliographies and other information 
related to buckwheat will also be published. Deadline for receiving manuscripts for volume 38: September 30, 2020, 
to e-mail address: ivan.kreft@guest.arnes.si
Page setup: Medija grafično oblikovanje d.o.o., Prečna ulica 6, 1000 Ljubljana.
Front page photo: Quantitative mineral-element distribution maps in a representative Tartary buckwheat 
(Fagopyrum tataricum) grain cross-section (See paper of Pongrac et al.).
FAGOPYRUM volume 37(1) (2020)
CONTENTS
ORIGINAL PAPERS
Application of micro-PIXE (particle induced X-ray emission) to study buckwheat grain 
structure and composition
Paula PONGRAC, Mitja KELEMEN, Primož VAVPETIČ, Katarina VOGEL-MIKUŠ, Marjana REGVAR,  
Primož PELICON  .......................................................................................................................................................  5
Flavonoid concentration in milling fractions of Tartary and common buckwheat
Blanka VOMBERGAR, Vida ŠKRABANJA and Mateja GERM  .............................................................................  11
OBITUARY
Toshiko Matano
Ivan KREFT  .............................................................................................................................................................  23
NOTE
Note on the 14th International Symposium on Buckwheat at North-Eastern  
Hill University, Shillong, India from Sept. 3 to 6, 2019.
Ivan KREFT  .............................................................................................................................................................  25
INFORMATION
Information for authors  ........................................................................................................................................ 27

Research paper
Application of micro-PIXE (particle induced X-ray 
emission) to study buckwheat grain structure and 
composition
Paula PONGRAC1,*, Mitja KELEMEN1, Primož VAVPETIČ1, Katarina VOGEL-MIKUŠ1,2, 
Marjana REGVAR2, Primož PELICON1
1 Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
2 Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia
* Corresponding author:
 Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
 Tel: +38651222963. 
 E-mail addresses: paula.pongrac@ijs.si; mitja.kelemen@ijs.si; primoz.vavpetic@ijs.si; katarina.vogelmikus@bf.uni-lj.si; 
marjana.regvar@bf.uni-lj.si; primoz.pelicon@ijs.si
DOI https://doi.org/10.3986/fag0012
Received: April 18, 2020; accepted: May 6, 2020
Keywords: Tartary buckwheat, micro-PIXE, elements, calcium, magnesium, phosphorus, sulphur, embryo,  
grain tissues, spatial distribution 
ABSTRACT
Tartary buckwheat (Fagopyrum tataricum Gaertn.) is a gluten-free pseudo-cereal crop with a grain nutrient profile 
that makes it an excellent alternative foodstuff. The distribution of calcium (Ca), magnesium (Mg), phosphorus (P) and 
sulphur (S) was investigated by micro-PIXE (particle induced X-ray emission) to resolve allocation and concentration of 
the elements in nine distinct grain tissues. Magnesium, P and S were preferentially allocated to the cotyledons and the 
embryonic axis (both inner and outer tissues), and Ca was predominant in the pericarp where two Ca-rich layers were 
observed. Allocation of P and S to aleurone suggests that this layer of cells, although not as prominent as in cereal grain, 
is rich in phytate and proteins. Quantitative information on spatial distribution of mineral elements in the edible grain 
may be useful in the technological processing of the grain and particularly in reducing the amount of mineral-element 
loss during milling.
Fagopyrum 37(1):5-10 (2020)
5
INTRODUCTION
Over four decades ago, an interdisciplinary research 
team comprising scientists from the Jožef Stefan In-
stitute and the Biotechnical Faculty, University of Lju-
bljana began a fruitful collaboration with the aim to 
study elemental composition of edible crop tissues, in 
particular the presence of S in protein-rich seeds (Bud-
nar et al., 1980; Kump et al., 1977, 1976; Rupnik et 
al., 1977). Among other goals, they planned to employ 
a recently developed technique, the particle induced 
X-ray emission (PIXE), which enables a quantitative 
analysis of biologically relevant elements in plant tis-
sue. The technique was at its infancy and two main 
obstacles prevented significant progress: i) the size of 
the analytical beam (in millimetre range) exceeded the 
size of the regions of interest several-fold and ii) the 
energy range of the beam was inappropriate, leading 
to irreparable radiation damage to biological samples. 
Eventually, the beamline was equipped with magnetic 
lenses to focus the ion beam into the micrometre scan-
ning resolution (micro-PIXE), following the elegant 
original demonstration on wheat (Triticum aestivum 
L.) grain (Mazzolini et al., 1985). Along with that the 
beam energy profile was optimized. First high-quality 
element distribution maps were acquired almost thirty 
years after the discouraging initial attempts. The case 
study was common buckwheat (Fagopyrum esculentum 
Moench) grain (Vogel-Mikuš et al., 2009), followed 
by the analysis with improved lateral resolution (Pon-
grac et al., 2011). The detailed element distributions 
in Tartary buckwheat grain corroborated observations 
in common buckwheat grain in which the largest con-
centrations of Mg, P, S, potassium (K), iron (Fe) and 
zinc (Zn) were found in cotyledons and that of Ca in 
pericarp (Pongrac et al., 2013a). By contrast, 7-day-old 
cotyledons of Tartary buckwheat sprout relocated Ca to 
inter-vascular mesophyll, Mg to mesophyll and S to ep-
idermis (Pongrac et al., 2016a). The described progress 
was accompanied using complementary techniques 
such as scanning electron microscopy and fluorescence 
microscopy (Francisco and Kreft, 1989; Javornik and 
Kreft, 1980; Kreft and Kreft, 2000) and synchrotron 
radiation micro X-ray fluorescence mapping (Pongrac 
et al., 2013a; 2016b; 2016c; 2017). This short review 
emphasises tissue-specific allocation of Ca, Mg, P and 
S in Tartary buckwheat grain and specifically focuses 
on elemental composition of aleurone and embryonic 
axis.
MATERIALS AND METHODS
Tartary buckwheat grain was provided by a local 
grower (cultivar ‘Zlata’, Mlin Rangus, Dolenje Vrhpolje at 
Šentjernej, Slovenia) in 2018. The grain was soaked for 
4 h in Milli-Q water at 4°C, hand-cut into 2-mm-thick 
cross-sections (perpendicular to the embryonic axis) 
with a sharp stainless-steel platinum-coated razor blade, 
frozen in liquid nitrogen and freeze dried for 2 days at 
−24 °C and 0.120 mbar. The hand-cut dried sections were 
mounted between two layers of Pioloform foil stretched 
over aluminium frames (Vogel-Mikuš et al., 2009, 2014). 
The spatial distribution of the mineral elements was de-
termined using micro-PIXE set-up of the Jožef Stefan 
Institute, Slovenia, as described previously (Lyubeno-
va et al., 2012; Pongrac et al., 2013b). The quantitative 
mineral element distribution maps were generated using 
the GEOPIXE II software package (Ryan, 2000) and tis-
sue-specific concentrations were extracted from the nu-
merical matrices obtained with the GEOPIXEII software, 
using the ImageJ programme (Abràmoff et al., 2004).
RESULTS AND DISCUSSION
Quantitative distribution maps of Ca, Mg, P and S in 
Tartary buckwheat grain are shown in Fig. 1. 
Allocation of Ca to pericarp (Fig. 1A), where two dis-
tinct Ca-rich layers (one in inner pericarp and another in 
outer pericarp) were observed in agreement with previ-
ous observations in common buckwheat (Pongrac et al., 
2011; Vogel-Mikuš et al., 2009) and other crops: different 
cereal grain (Antonini et al., 2018; Pongrac et al., 2013c; 
Ren et al., 2007; Singh et al., 2014) and legume seed 
(Cominelli et al., 2020). A poor mobility of Ca in phloem 
(White and Broadley, 2003) and consequently the limit-
ed translocation of Ca from maternal (pericarp) to filial 
(embryo and endosperm) grain tissues may explain this 
observation. On average 3,000 mg Ca kg-1 was found in 
pericarp, which was 20 times more than in endosperm 
and 4 times more than in cotyledons (Fig. 2). 
Calcium is the only element to exhibit such distinct 
allocation to pericarp (Fig. 1). Magnesium is allocated to 
cotyledons and embryonic axis, with some Mg found also 
in the outer layer of pericarp (Fig. 1B). In pericarp the 
average Mg concentration was 4 times smaller than in 
cotyledons (8,600 mg kg-1 dry weight); and in endosperm 
4 times smaller (Fig. 2). Phosphorus is clearly allocated to 
cotyledons and the embryonic axis (Fig. 1C). The largest P 
concentration is found in the outer layer of embryonic axis 
Pongrac et al. (2020): Application of micro-PIXE to study buckwheat grain
6
(Fig. 2). Phosphorus distribution can be used as an ap-
proximation of the location of phytate, a salt of phytic 
acid which strongly binds (even immobilizes) some essen-
tial mineral elements (mainly the divalent cations), such 
as Mg, manganese, (Mn), Fe and Zn in grain and seed 
(Hallberg et al., 1987; Pongrac et al., 2013a; Regvar et al., 
2011). The co-localisation of Mg and P in Fig. 1 illustrates 
the fact. During germination these mineral elements are 
being enzymatically released to become available for the 
growth of the seedling. Endosperm and pericarp contain 
around 30-times less P per unit mass than the embryo 
(Fig. 2). Sulphur, on the other hand, can be used as an 
indicator of proteins (Budnar et al., 1980; Kump et al., 
1976), being present in two common amino acids, me-
thionine and cysteine. In wheat grain, S was mainly locat-
ed in sub-aleurone layer reflecting a significant presence 
of proteins in these cells (Pongrac et al., 2013c; Singh et 
al., 2014; Tosi et al., 2009), whereas in Tatary buckwheat 
grain, S is allocated mainly, to cotyledons and the em-
bryonic axis (Fig. 1D; (Pongrac et al., 2013a)). However, 
there is a thin layer enriched in Mg, S and P just under 
the pericarp, surrounding the endosperm. This is aleu-
rone, which is in contrast to cereal grain, a layer of small 
cells (approximately 10-15 µm in thickness) in buck-
wheat grain (Javornik and Kreft, 1980). Because aleurone 
of buckwheat grain is so inconspicuous (often strongly 
attached to the cotyledons) it is seldom mentioned, al-
though it has been previously noticed in common buck-
wheat (Vogel-Mikuš et al., 2009). In buckwheat grain the 
aleurone is known to contain large concentration of pro-
Figure 1 Quantitative mineral-element distribution maps in a representative Tartary buckwheat (Fagopyrum tataricum) grain cross-
section, comprising a centrally-positioned embryonic axis, a pair of cotyledons surrounding the endosperm and the pericarp. Distribution map 
of calcium (Ca; A), magnesium (Mg; B), phosphorus (P; C) and sulphur (S; D). The colour scales are in weight %.
Fagopyrum 37(1):5-10 (2020)
7
teins, as also supported by the S distribution maps shown 
here.
For optimum evaluation of nutritional quality of 
buckwheat grain the elemental distribution maps should 
be complemented with distributions of secondary me-
tabolites as accessible with MeV secondary ion mass 
spectrometry, currently being developed at the nuclear 
microprobe at the Jožef Stefan Institute. Because buck-
wheat grain contains large concentrations of rutin and 
quercetin (Fabjan et al., 2003), antioxidants exhibiting 
positive impact on human health, understanding their 
allocation will have important consequences in planning 
milling fractions and further grain processing.
CONCLUSIONS
Results demonstrate that in Tartary buckwheat grain 
Mg, P and S, are preferentially allocated to the cotyledons 
and the embryonic axis (both inner and outer tissues), 
while Ca presence is predominant in the pericarp, where 
two Ca-rich layers can be observed. Phosphorus and S 
distributions can be used as indicators for phytate and 
protein distribution, respectively. Understanding the 
quantitative distribution of mineral elements is essen-
tial for the technological processing of the grain, with an 
impact on the amount of mineral-element loss during 
milling.
ACKNOWLEDGEMENTS
This study was financed by the Slovenian Research 
Agency, through programmes P1-0143, P1-0212, P1-
0112 and I0-0005, basic projects (N7-0077, J7-9418, 
J7-9398, N1-0105 and N1-0090) and the applied project 
L4-9305, co-financed by the Ministry of Agriculture, For-
estry and Food, Republic of Slovenia. The funding organ-
izations had no role in the design, analysis or writing of 
this article. The authors are grateful to Prof. Alojz Kodre 
for reading early version of the manuscript and for his 
English editing.
Figure 2 A schematic picture of the Tatary buckwheat (Fagopyrum tataricum) grain cross-section and corresponding average concentration  
(mg kg-1 dry weight; in bold) with standard error of measurement (in italics) for calcium (Ca), magnesium (Mg), phosphorus (P) and sulphur 
(S) as extracted from the distribution maps.
Pongrac et al. (2020): Application of micro-PIXE to study buckwheat grain
8
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IZVLEČEK
Namen raziskave je bil proučiti razporeditev esencialnih elementov kalcija (Ca), magnezija (Mg), fosforja (P) in žvep-
la (S) v tkivih zrna tatarske ajde s tehniko mikro-PIXE (z delci inducirana emisija rentgenskih žarkov), ki omogoča kvan-
titativno analizo elementov z ločljivostjo enega mikrometra. Kemijska priprava zrna pri tehniki mikro-PIXE ni potrebna. 
Največje koncentracije Ca smo izmerili v luski, v kateri sta bili jasno vidni dve s Ca bogati plasti. Magnezija, P in S je 
bilo največ v kličnih listih in v tkivih embrionalne osi. Ker lahko razporeditev P in S uporabimo kot oceno razporeditve 
fitatov in beljakovin, sklepamo, da je s P in S bogat tanek sloj, ki obdaja celotno zrno in je jasno viden predvsem na delu, 
kjer meji na endosperm, v bistvu sloj alevronskih celic, v katerih so prisotni fitati in zlasti beljakovine. Kvantitativne 
informacije o prostorski porazdelitvi mineralnih elementov v zrnu so koristne pri razvoju tehnološke predelave zrnja in 
pri zagotavljanju zmanjšanja izgube mineralnih elementov med mletjem.
Pongrac et al. (2020): Application of micro-PIXE to study buckwheat grain
10
Research paper
Flavonoid concentration in milling fractions of 
Tartary and common buckwheat
Blanka VOMBERGAR1, Vida ŠKRABANJA2 and Mateja GERM*2
1 Education Centre Piramida Maribor, SI-2000 Maribor, Slovenia
2 Biotechnical Faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia
* Corresponding author: Mateja Germ, Biotechnical Faculty, University of Ljubljana, SI-1000 Ljubljana, Slovenia
E-mail addresses of authors:  
blanka.vombergar@guest.arnes.si, vida.skrabanja@guest.arnes.si, Mateja.Germ@bf.uni-lj.si
DOI https://doi.org/10.3986/fag0013
Received: December 5, 2019; accepted: March 30, 2020
Keywords: common buckwheat, Tartary buckwheat, flavonoids, milling, hydrothermal treatment 
ABSTRACT
Common buckwheat (Fagopyrum esculentum Moench) and Tartary buckwheat (F. tataricum Gaertn.) samples were 
used in milling, sieving and analysing experiments. Flavonoids were analysed in buckwheat samples, in milling and 
sieving fractions and after the contact of flour particles with water, to simulate conditions in dough.
In Tartary buckwheat, there was even more than 100-times higher content of flavonoids flour in comparison to 
respective fractions of common buckwheat flour. The highest concentration of flavonoids in milling fractions of Tartary 
buckwheat flour (granulation over 100 µm up to including 1000 µm) was established as 3.5–4.5% flavonoids/DM. 
Immediately after the direct contact of flour particles of common and Tartary buckwheat with water the apparent 
concentration of flavonoids rose (even for 100% or more) in the first 5–30 minutes of contact. After one hour, due to the 
degradation of flavonoids, their concentration decreased. Concentration of flavonoids are after 24 hours of contact of 
flavonoids with water in all milling fractions lower in comparison to the value after first 5 minutes of contact with water.
Fagopyrum 37(1):11-21 (2020)
11
INTRODUCTION
Buckwheat is used as a food ingredient after husking, 
milled, prepared at different temperatures and in a diver-
sity of media, predominantly in water. Research imita- 
ting real technological process producing foods and dishes 
from buckwheat are important for evaluating nutritional 
value of foods based on buckwheat. In buckwheat grain 
there are important polyphenolic substances, including 
flavonoids. Among consumers of buckwheat foods and 
dishes there is growing interest for the composition and 
nutritional value of products.
Among buckwheat species and cultivars there are 
differences in content of flavonoids, including rutin. The 
concentration of flavonoids may depend on genotype, 
development phases, weather, altitude, year of growing 
and harvest, storage and other factors. Different plant 
parts may contain different content of flavonoids. Se- 
veral authors report higher content of rutin in Tartary 
buckwheat in comparison to common buckwheat (Su-
zuki et al., 2002; Fabjan et al., 2003; Lin, 2004; Asami 
et al., 2007; Fabjan, 2007). There could be as well dif-
ferences among samples of Tartary buckwheat. Several 
authors (Fabjan et al., 2003; Briggs et al., 2004; Chai et 
al., 2004; Park B.J. et al., 2004; Suzuki et al., 2005; Jiang 
et al., 2007; Ghimeray et al., 2009, Kreft, 2013; Kreft et 
al., 2013; Kreft et al., 2016ab; Kreft 2016; Germ et al., 
2019) report about diverse results on samples of buck-
wheat. According to Liu in Zhu (2007) the main flavonoid 
in Tartary buckwheat is rutin, along with quercetin and 
quercitrin (Fabjan, 2007; Morishita et al., 2007). In the 
grain of common buckwheat there are flavonoids rutin, 
epicatechin and epicatechingalat. Dietrych-Szostak and 
Oleszek (1999) isolated from common buckwheat 6 fla-
vonoids, namely rutin, quercetin, orientin, vitexin, isovi-
texin and isoorientin. Rutin and isovitexin in dehusked 
buckwheat grain and all 6 of them in husk. Some litera-
ture data are presented in Table 1.
Crushing, milling and sieving are the main procedures 
to obtain buckwheat milling fractions. The gain of flour is 
in buckwheat normally about 40–50% of the total mass 
of grain. The rest are husks and peripheral parts of grain 
(testa, cotyledons). Peripheral parts of grain are crushed 
differently in comparison to endosperm, and they do 
not pass the fine sieves. Cotyledons are richer in rutin 
in comparison to endosperm, so flour may contain less 
rutin in comparison to the whole grain (Kreft, 1995). The 
methods of treatment of the grain, like husking, crush-
ing, milling and sieving have an impact on the concentra-
tion of flavonoids and other polyphenolic substances. As 
well as the presence of husk and bran particles in darker 
flour milling fractions may also have impact on the flavo-
noids and other polyphenolic substances. Allocation of 
flavonoids in different parts of buckwheat grain have im-
pact on the utilization value of milling fractions. Know- 
Buckwheat species Sample
Flavonoid  
concentration Reference
Common buckwheat Grain 24.4 µg/mg Ghimeray et al. (2009)
Common buckwheat Grain 0.04% Jiang et al. (2007)
Common buckwheat Grain 18.8 mg/100 g DM Dietrych-Szostak in Oleszek (1999)
Tartary buckwheat Grain 142.2 µg/mg Ghimeray et al. (2009
Tartary buckwheat Grain 2.04 % Jiang et al. (2007)
Common buckwheat 16 milling fractions 2.35–135.4 mg/100 g Hung in Morita (2008)
Common buckwheat Flour from shop (Slovenia) 0.016 Avguštin (2009)
Common buckwheat Flour 0.0098 %/DM Quettier-Deleu et al. (2000)
Common buckwheat Husk 0.0456 %/DM Quettier-Deleu et al. (2000)
Common buckwheat (diverse cultivars) Husk 102.1–151.5 mg/100 g Dietrych-Szostak (2004)
Common buckwheat Husk 74 mg/100 g DM Dietrych-Szostak in Oleszek (1999)
Common buckwheat Bread  (mixed: wheat, buckwheat) 7.76–26.9 mg/kg Bojňanská et al. (2009) 
Tartary buckwheat (Korea) Sprouts powder 24 g/kg Gadžo et al. (2009)
Table 1: Flavonoid content in buckwheat grain, husks and milling fractions
Vombergar et al. (2020): Flavonoid concentration in milling fractions
12
ledge about the distribution of flavonoids in milling frac-
tions, in the relation to the size of particles (granulation) 
is of importance for the simple, swift, and efficient way 
of obtaining flavonoid-rich milling fractions, especially in 
Tartary buckwheat. 
MATERIAL IN METHODS
Material
Common buckwheat (Fagopyrum esculentum Moench) 
and Tartary buckwheat (F. tataricum Gaertn.) samples 
were used in milling, sieving and analysing experiments. 
Two samples (T1 and T2) of Tartary buckwheat were in-
cluded, obtained from Luxemburg and a sample of com-
mon buckwheat (variety Darja, sample D), obtained from 
Biotechnical faculty, Ljubljana, Slovenia. By milling and 
sieving of Tartary buckwheat sample T1 and common 
buckwheat four fractions were obtained with different 
granulations. Each of them was mixed with water. Sam-
ple T2 was obtained as flour, which was sieved into two 
fractions with different granulation. 
Methods
Samples T1 and D were milled by cereal mill Quadro-
mat Junior Model No. 08 801 01 (Brabender Duisburg, 
Germany), to obtain two fractions by planary sieves (Ta-
ble 2).
To the flour fractions, water was added and the dough 
was made. Amount of added water and contact time flour/
water prior to freezing is reported in Table 3. Fractions 
over 1000 µm (T1 F22 and D F22) contained mainly husk 
and some bran, so they were just rinsed in water (Table 3). 
After 30 days of storage below, the samples were freeze-
dried. By spectrophotometric analyses (spectrophoto- 
meter TECAN Genios), using 5% AlCl3 (reaction between 
flavonoids and AlCl3), which results in yellow colour with 
maximum at 420 nm (Dutra, 2008; Zhang et al., 2005; 
Bohm, 1997), concentration of flavonoids was deter-
mined. Statistical analyses were performed using Micro-
soft Excel 2003 and program STAT G (Statgraphics 5.0, 
Statistical Graphics Corporation, ZDA), and by ANOVA, 
significance was accepted at p<0.05 (Ferligoj, 1997; Fer-
ligoj and Lozar Manfreda, 2009). All measurements and 
analyses were performed in three independent samples.
RESULTS
Milling fractions of studied common and Tartary 
buckwheat samples contained very different amount of 
flavonoids (Table 4). Concentration of flavonoids was 
(sample D) much lower in common buckwheat in compar-
ison to Tartary buckwheat (Table 4, Fig. 1.) Comparison 
of respective fractions of Tartary buckwheat T1 and com-
mon buckwheat D (Table 4, Fig. 1.) showed much higher 
(50 do 100-times higher) concentration of flavonoids in 
Sample Process Fractions Further process Subfractions Granulations
Tartary buckwheat, grain
(T1) Milling
T1 F1 Sieving
T1 F11 ≤ 100 µm
T1 F12 100 µm < x ≤ 236 µm
T1 F2 Sieving 
T1 F21 236 µm < x ≤ 1000 µm
T1 F22 > 1000 µm and bran, husk
Common buckwheat Darja, grain
(D) Milling 
D F1 Sieving 
D F11 ≤ 100 µm
D F12 100 µm < x ≤ 236 µm
D F2 Sieving 
D F21 236 µm < x ≤ 1000 µm
D F22 > 1000 µm and bran, husk
Tartary buckwheat – flour (T2) / / Sieving 
T2 F11 ≤ 100 µm
T2 F12 >100 µm
T1 - Tartary buckwheat, flour from entire grain 
D - Common buckwheat Darja, flour from entire grain 
T2 - Tartary buckwheat, obtained as flour
Table 2: Milling and sieving of common buckwheat (sample D) and Tartary buckwheat (samples T1 and T2) with characterization of fractions
Fagopyrum 37(1):11-21 (2020)
13
T1 - Tartary buckwheat, whole grain flour 
D - Common buckwheat, whole grain flour 
T2 F1 - Tartary buckwheat flour
Sample 
No. Sample Mass (g)
Water addition
(mL)
Contact times (flour and water) 
prior to freezing Freezing and storage
Tartary buckwheat (T1) –  
milling fractions
0.08 h, 1 h, 2 h, 
4 h, 8 h, 12 h, 24 h
0.5 h: –35 °C to –40 °C; 
 1 month: –15 °C to –20 °C 
1 T1 F11 250 200 SAME SAME
2 T1 F12 125 100 SAME SAME
3 T1 F21 100 130 SAME SAME 
4 T1 F22 125 200 SAME SAME
Common buckwheat (D) – 
milling fractions
0.08 h, 1 h, 2 h, 
4 h, 8 h, 12 h, 24 h
0.5 h: –35 °C to –40 °C; 
1 month: –15 °C do –20 °C 
5 D F11 250 200 SAME SAME
6 D F12 250 200 SAME SAME
7 D F21 250 235 SAME SAME 
8 D F22 250 400 SAME SAME
Tartary buckwheat flour  
(T2) 
0.08 h, 1 h, 2 h, 
4 h, 8 h, 12 h, 24 h
0.5 h: –35 °C to –40 °C; 
1 month: –15 °C to –20 °C 
9 T2 F1 250 200 SAME SAME
10 T2 F11 200 160 SAME SAME
11 T2 F12 200 160 SAME SAME 
Table 3: Dough samples being prepared for freezing
Sample Subfraction
Flavonoids
Milled sample
Dough (flour and water)
0.08 h (5 min)
Dough (flour and water)
24 h
%/DM %/DM %/DM 
Tartary buckwheat (T1) T1 F11 0.709 1.444 1.112 
Tartary buckwheat (T1) T1 F12 4.470 4.766 4.311 
Tartary buckwheat (T1) T1 F21 3.542 4.262 3.551 
Tartary buckwheat (T1) T1 F22 0.178 0.178 0.062 
Common buckwheat Darja (D) D F11 0.015 0,017 0.006 
Common buckwheat Darja (D) D F12 0.043 0.085 0.042 
Common buckwheat Darja (D) D F21 0.051 0,088 0.069 
Common buckwheat Darja (D) D F22 0.055 0.071 0.055 
Tartary buckwheat (T2) T2 0.916 1.226 0.955 
Tartary buckwheat (T2) T2 F11 0.243 0.363 0.199 
Tartary buckwheat (T2) T2 F12 1.011 2.639 2.063 
T1 - Tartary buckwheat (from grain)
D - Common buckwheat Darja (from grain)
T2 - Tartary buckwheat (from flour) 
DM - dry matter
Table 4: Comparison of flavonoid content in milling fractions of Tartary and common buckwheat (samples T1,T2, D) and in milling  
fractions with added water after 5 minutes and after 24 hours of flour-water contact
Vombergar et al. (2020): Flavonoid concentration in milling fractions
14
Figure 1: Comparison of flavonoid content in milling fractions of common and Tartary buckwheat
T1 F11 - Tartary buckwheat flour, granulation ≤ 100 µm
T1 F12 - Tartary buckwheat flour, granulation 100 µm < x ≤ 236 µm
T1 F21 - Tartary buckwheat flour, granulation 236 µm < x ≤ 1000 µm
T1 F22 - Tartary buckwheat flour, granulation > 1000 µm, including bran and husk 
D F11 - Common buckwheat flour, granulation ≤ 100 µm
D F12 - Common buckwheat flour, granulation 100 µm < x ≤ 236 µm
D F22 - Common buckwheat flour, granulation > 236 µm < x ≤ 1000 µm
D F22 - Common buckwheat flour, granulation >1000 µm, including bran and husk 
T2 F1 - Tartary buckwheat flour, additional sample
T2 F11 - Tartary buckwheat flour, additional sample, granulation ≤ 100 µm 
T2 F12 - Tartary buckwheat flour, additional sample Granulation >100 µm
Tartary buckwheat milling fractions in comparison to 
respective common buckwheat milling fractions. How-
ever, among fractions, containing mainly husk and bran, 
in Tartary buckwheat it was only about 3 times more 
flavonoids at Tartary buckwheat in comparison to com-
mon buckwheat. In the investigated samples the highest 
concentration of flavonoids was in the range 3.5–4.5% 
in dry matter in milling fractions of Tartary buckwheat 
T1 (with granulation over 100 µm, including up to 1000 
µm). These are milling fractions of dark coarse flours. 
Fraction of Tartary buckwheat husk had low content of 
flavonoids. Interestingly, husk fraction of common buck-
wheat had a high content of flavonoids, in comparison to 
other milling fractions of common buckwheat. 
Concentration of flavonoids was different between 
two samples of Tartary buckwheat (Table 4, Fig. 1). In 
comparison of two fine milled light Tartary buckwheat 
flours (T1 in T2) with the same granulation (up to in-
cluding 100 µm) we established different content of 
flavonoids (Table 4, Fig. 1), in both cases the concentra-
tion of flavonoids was very low. Comparison of Tartary 
buckwheat sample T1 and common buckwheat D showed 
different allocation of flavonoids among milling fractions 
(Fig. 1). In the Table 4 it was reported that in common 
buckwheat milling fractions with the granulation up to 
100 µm it was much less flavonoids in comparison to 
fractions over 100 µm. Highest concentration was in the 
fraction F22 (husk and bran), and lowest in the fraction of 
light flour F11.
It was studied the content of flavonoids in the dough, 
made from different milling fractions of Tartary and 
common buckwheat (samples T1, T2, D) after first 5 min-
utes, and up to 24 hours of contact of flour particles with 
added water (Table 5; Fig. 1). 
Fagopyrum 37(1):11-21 (2020)
15
Impact of water on the flavonoids concentration was 
similar for common and Tartary buckwheat (Figs. 2 and 
3, Table 4). Apparent flavonoid concentration in most of 
milling fractions rose for about 2 times in the first five 
minutes after the addition of water, in comparison to un-
treated, dry samples. The highest elevation was in flavo-
noids concentration in coarse and fine flours (coarse and 
fine), and somewhat less in fractions with bran and husk. 
With few exceptions, it was gradually decreased during 
24 hours of contact of flour particles with water. Gra- 
dual lowering of flavonoid concentration in the time 0.08 
to 24 hours was different among samples and fractions, 
but lowering from apparent flavonoid concentration in 
the time 0.08 to 24 hours was a general appearance, it 
was a linear correlation among time and flavonoid con-
centration (r2 = 0,9953; p<0,05; y = – 0,0733 + 0,8739x). 
Only in the fraction of bran and husk (F22) flavonoids 
concentration was after 24-hours of contact of particles 
a Tartary buckwheat T1 F11 b Tartary buckwheat T1 F12
Figure 2: Flavonoid concentrations in dough from different milling fractions of Tartary buckwheat (T1) over a 24-hour time period
T1 F11 - Tartary buckwheat, granulation ≤ 100 µm
T1 F12 - Tartary buckwheat, granulation 100 µm < x ≤ 236 µm
T1 F21 - Tartary buckwheat, granulation 236 µm < x ≤ 1000 µm
T1 F22 - Tartary buckwheat, granulation > 1000 µm including bran and husk 
0.08 - 5 minutes; 0.5 - 30 minutes, 1 – one hour; 2,4,8,12,24 – hours of contact with water
c Tartary buckwheat T1 F21 d Tartary buckwheat T1 F22
with water as low as 60 %, in comparison to starting con-
centration before the addition of water. 
DISCUSSION 
From the point of view of functionality most inte- 
resting are milling fractions with the granulation over 
100 µm up to including 1000 µm (the milling gain of 
these fractions is about 30%); from point of view of 
nutritional functionality less interesting fractions are 
fine light flours with the granulation below 100 µm (in 
milling the gain of light flours is nearly about 50%), as 
they are poor in flavonoids, and also contain low concen-
tration of proteins and minerals (Vombergar, 2010). Col-
lection and mixing of fractions (with the granulation over 
100 µm up to including 1000 µm), especially in Tartary 
buckwheat is the best possibility to obtain flour material 
rich in flavonoids, proteins and minerals.
Vombergar et al. (2020): Flavonoid concentration in milling fractions
16
Highest concentration of flavonoids was established in 
Tartary buckwheat T1 in milling fractions with the gran-
ulation over 100 up to 1000 µm (fractions F12 and F21), 
namely 3.54–4.47% (Table 4). This is about 100-times 
more in comparison to the concentration of flavonoids 
in common buckwheat Darja with the same granulation 
groups (0.043–0.051%) (Table 4, Fig. 1). The results are in 
line with previous results about the difference in flavonoid 
concentration in common and Tartary buckwheat (Piao in 
Li, 2001; Škrabanja et al., 2004; Hung in Morita, 2008). 
It was established that in common buckwheat it is 
not similar distribution of flavonoids among fractions 
as in the case of Tartary buckwheat (Table 4, Fig. 1). 
In common buckwheat it is the richest with flavonoids 
the fraction of bran and husk F22 with granulation over 
1000 µm (D F22 0.055 % flavonoids), what was not the 
case in Tartary buckwheat. This is the reason for the in-
tensive research of the concentration of flavonoids, espe-
cially rutin, in the husk of common buckwheat (Oomah 
a Common buckwheat D F11 b Common buckwheat D F12
Figure 3: Flavonoid concentrations in dough from different milling fractions of common buckwheat (D) over a 24-hour time period
D F11 - Common buckwheat, subfraction with granulation ≤ 100 µm
D F12 - Common buckwheat, subfraction with granulation 100 µm < x ≤ 236 µm
D F22 - Common buckwheat, subfraction with granulation > 236 µm < x ≤ 1000 µm
D F22 - Common buckwheat, subfraction with granulation >1000 µm and bran, husk 
0.08 - 5 minutes; 0.5 - 30 minutes, 1 – one hour; 2,4,8,12,24 – hours of contact with water
c Common buckwheat D F21 d Common buckwheat D F22
in Mazza, 1996; Watanabe et al., 1997; Dietrych-Szostak 
and Oleszek, 1999; Kreft et al., 1999; Quettier-Deleu 
et al., 2000; Steadman et al., 2001b; Dietrych-Szostak, 
2004). We detected lower difference in the content of 
flavonoids between common and Tartary buckwheat in 
the fraction of husk, than between fractions of flours. So, 
we suggest the possibility for using of husk of common 
buckwheat as a source of flavonoids, especially in areas, 
where Tartary buckwheat is not a traditional crop, as they 
grow common buckwheat. 
Milling affects the release of flavonoids during the ex-
traction of buckwheat polyphenols. Size of particles is an 
important characteristic of flours. Smaller particles have 
relatively higher surface area, so the action of enzymes 
could be different in comparison to crude flour parti-
cles. Enzymes in fine milled flours with small particles 
could be more active. Polyphenols are included in many 
cell components. So, their extraction to the liquid phase 
could be different.
Fagopyrum 37(1):11-21 (2020)
17
Suzuki et al. (2002) and Yasuda (2001, 2007) are 
reporting about the enzyme flavonol-3-glukosidase, im-
portant for the degradation of rutin in buckwheat under 
certain conditions. This enzyme is located in grain in the 
testa and cotyledons. Predominant amount of enzyme is 
in cotyledons, but more active is enzyme stored in tes-
ta (Suzuki et al., 2002). Rutin is degraded to quercetin. 
Suzuki et al. (2004) reported about the correlation of 
enzyme concentration in buckwheat flour with the con-
centration of water soluble acids. Mukasa et al. (2009) 
established that rutin in the husked round formed buck-
wheat grain is degraded quickly but it is not the case in 
soaked intact grain. It is supposed that this is due to struc-
tural isolation of rutin to the rutin degraded enzymes. 
There are different ways of rutin degradation, for ex-
ample the oxidation of rutin and some other biochem-
ical reactions, transferring rutin to other metabolites. 
Enzymes, degrading rutin could be blocked in their func-
tion. Steaming, cooking and extruding preserve a part 
of rutin and may prevent the appearance of bitter taste 
(Paulíčková et al., 2004). Mukasa et al. (2009) confirmed 
that most of rutin remain in grain after cooking one hour. 
Thermal treatment may have impact on the degradation 
of flavonoids according to Dietrych-Szostak in Oleszek 
(1999). Şensoy et al. (2006) reported that roasting, treat-
ment with dry hot air, has no impact on antioxidative 
properties of light or dark buckwheat flour.
Simulation of technological process of dough making 
(contact of flour with water) revealed the biochemical 
events, with impact to some dough constituents (mainly 
flavonoids – rutin and quercetin).
CONCLUSION
In regard to functional aspect and nutritional value 
are most interesting buckwheat milling fractions with 
granulation over 100 µm up to including 1000 µm (mill-
ing gain about 30%); less interesting are fractions of light 
fine flours with granulation less than 100 µm (milling 
gain nearly 50%), which does not contain much proteins, 
minerals and flavonoids. Collecting and mixing of frac-
tions with granulation over 100 µm up to including 1000 
µm), especially at Tartary buckwheat is the best possibil-
ity to get flour of high nutritional and functional value, 
because of flavonoids, proteins and minerals. 
Tartary buckwheat has a much higher content of fla-
vonoids in comparison to common buckwheat, even more 
than 100-times more in Tartary buckwheat flour in com-
parison to common buckwheat flour. The highest concen-
tration of flavonoids in milling fractions of Tartary buck-
wheat flour T1 (granulation over 100 µm up to including 
1000 µm) was established as 3.5–4.5% flavonoids/DM. 
Flavonoids in milling fractions with different granu-
lation are differently allocated. Allocation is different in 
Tartary buckwheat and common buckwheat.
Immediately after the direct contact of flour particles 
of common and Tartary buckwheat with water the ap-
parent concentration of flavonoids rose (even for 100% 
or more) in the first 5–30 minutes of contact. After one 
hour, due to the degradation of flavonoids, their concen-
tration became lower. Concentration of flavonoids are 
after 24 hours of contact of flavonoids with water in all 
milling fractions lower in comparison to the value after 
first 5 minutes of contact with water. 
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ACKNOWLEDGEMENTS
This study was financed by the Slovenian Research Agency, through the applied project L4-9305, co-financed by the 
Ministry of Agriculture, Forestry and Food, Republic of Slovenia. 
IZVLEČEK
Z vidika funkcijskega dodatka ter hranilne in prehranske vrednosti so zanimive mlevske frakcije ajde z granulacijo 
nad 100 µm do vključno 1000 µm (teh je pri mletju okoli 30 %); nezanimive pa so frakcije finih belih mok z granulacijo 
pod 100 µm (pri mletju nastaja skoraj 50 % belih mok), saj so revne z beljakovinami, minerali in flavonoidi. Zbiranje 
in mešanje frakcij (z granulacijo nad 100 µm do vključno 1000 µm), predvsem pri tatarski ajdi, pomeni najboljšo izbiro 
glede vsebnosti beljakovin, mineralov in flavonoidov. 
Tatarska ajda ima bistveno višjo vsebnost flavonoidov kot navadna ajda (tudi več kot 100-krat več flavonoidov v 
moki). Najvišja vsebnost flavonoidov je v mlevskih frakcijah tatarske ajde T1 (z granulacijo nad 100 µm do vključno 
1000 µm) in sicer 3,5–4,5 % flavonoidov v sušini. 
Flavonoidi, se po mlevskih frakcijah (z različno granulacijo) različno razporejeni. Razporeditev med mlevskimi frak-
cijami ni enaka pri tatarski in navadni ajdi.
Pri neposrednem stiku mlevskih frakcij tatarske in navadne ajde z vodo vsebnost flavonoidov v vseh mlevskih frakci-
jah naraste (tudi za 100 % in več) v prvih 5–30-ih minutah delovanja. Po eni uri začne koncentracija flavonoidov padati 
zaradi razpada flavonoidov, oksidacijsko redukcijskih procesov, encimatskih procesov in drugih biokemijskih reakcij. 
Koncentracija flavonoidov po 24-ih urah stika moke z vodo je vedno nižja v primerjavi z začetno vrednostjo flavonoidov 
v testu po 5-tih minutah stika z vodo.
Fagopyrum 37(1):11-21 (2020)
21

DOI https://doi.org/10.3986/fag0014
On March 22, 2020, our dear friend and teacher Toshiko Matano,  
Professor Emeritus of Shinshu University, Nagano Prefecture, Japan,  
passed away at her home in Ina, Japan.
Toshiko Matano
Toshiko Matano was in 1980 one of the founding mem-
bers of the International Buckwheat Research Associa-
tion (IBRA). For 40 years, since 1980, Prof. Matano was a 
member of the international board of IBRA, making sig-
nificant contribution for the development of IBRA. Prof. 
Matano was one of emeritus editors of FAGOPYRUM 
journal. In 1995 she organised with Prof. Akio Ujihara the 
6th International Symposium on Buckwheat in Ina, Shin-
shu University, and in the period 1995-1998 she served 
as the Chair-person of IBRA. Among her contributions 
to the international buckwheat research community was 
the establishment of Buckwheat Gallery on www pages, 
and scanning of many important papers on buckwheat, 
including those presented at IBRA Symposia. Many of 
presentations scanned by T. Matano were all the time, 
and are even now, available on www pages, freely acces-
sible for scientists and other interested people. There are 
many users of papers published in this way, but it is less 
23
Fagopyrum 37(1):23-24 (2020)
known that they were scanned and served to the interna-
tional buckwheat community by Prof. Matano.
Prof. Matano made important steps for mutual un-
derstanding among scientists belonging to different na-
tions, and continents, belonging to different agricultural 
and food traditions, practices and cultures. Prof. Matano 
was a person filled with love and compassion for the sur-
rounding world and people, an outstanding scientist and 
teacher.
Toshiko Matano was born in Kyoto, Japan on May 4, 
1932, she graduated at the Laboratory of Crop Science, 
Department of Agronomy, Faculty of Agriculture, Kyoto 
University and there received her PhD degree. She got 
job at the Shinshu University at Ina, located at Minami 
Minowa village, Nagano Prefecture. Under the supervi-
sion of Prof. Toshiko Matano, many students of Shinshu 
University obtained their university degrees of different 
levels. Prof. Matano was a principal investigator of many 
research projects on Modeling of expression mechanism 
of productivity of common buckwheat, Adaptability of 
Tartary buckwheat to environmental factors, Studies on 
the historical relationship of agriculture between East 
and Southwest Asia – Agronomical and prehistorical 
analysis of natural and cultivated vegetation. She joined 
as well many other research projects. Prof. Matano stud-
ied Asian buckwheat noodles (soba) eating habits, as well 
in comparison to buckwheat groats (kasha, or kaša) dish-
es and culture in Slovenia, Czech Republic and Poland. 
On her research travels Prof. Matano visited among other 
countries as well South Korea, China, Afghanistan and 
Himalaya regions, Russia, Bosnia-Herzegovina, Croatia, 
many times Slovenia, and Italy, Czech Republic, Austria, 
Germany, Poland, Sweden, Finland, Canada, Australia 
and other countries. Among the significant publications 
of Prof. Toshiko Matano is a book on buckwheat (soba), 
in Japanese, with rich illustrations, for children, with 
co-author Eriko Hirano.
We will be missing very much the kind words, com-
pany, understanding and encouragements by Professor 
Emeritus Toshiko Matano.
Ivan Kreft 
24
25
Fagopyrum 37(1):25-26 (2020)
DOI https://doi.org/10.3986/fag0015
Note on the 14th International Symposium  
on Buckwheat at North-Eastern Hill University, 
Shillong, India from Sept. 3 to 6, 2019.
Ivan KREFT
The Department of Botany, North-Eastern Hill University 
(NEHU), Shillong, India in collaboration with ICAR-Na-
tional Bureau of Plant Genetic Resources (NBPGR), India, 
and DBT-Institute of Bioresources and Sustainable De-
velopment (IBSD), India organized the 14th International 
Symposium on Buckwheat at North-Eastern Hill Univer-
sity, Shillong from Sept. 3 to 6, 2019 at North Eastern 
Hill University, Shillong. The Symposium was organized 
under the ageis of International Buckwheat Research 
Association on the theme "DIVERSIFYING FOOD SYS-
TEMS FOR HEALTH AND NUTRITIONAL SECURITY". 
Prof. S. K. Srivastava, Vice Chancellor, North-Eastern 
Hill University was the Chief Patron of the Organizing 
Committee. Dr. Trilochan Mohapatra, Secretary, Depart-
ment of Agricultural Research and Education, Ministry 
of Agriculture Govt. of India and Director General, Indi-
an Council for Agricultural Research, Govt. of India was 
the Chairman of the International Scientific Advisory 
Committee of the Symposium. Prof. Nikhil Chrungoo of 
NEHU was the Organizing Secretary of the Symposium.  
Dr. J.C. Rana of Bioversity International and Dr. Aijaz Ah-
mad Wani of University of Kashmir, Srinagar, India were 
the Joint Secretaries of the Symposium. Sh. Tathagata 
Roy, Hon’ble Governor of the Indian province of Megha-
laya, graced the Inaugural function of the Symposium 
as the Chief guest and   inaugurated the symposium. 
26
Dr. Trilochan Mohapatra, Secretary (DARE), Ministry of 
Agriculture Govt. of India and DG, ICAR, New Delhi was 
the Guest of Honour in the inaugural function. Prof. S. 
K. Srivastava, Vice Chancellor, North-Eastern Hill Uni-
versity, Shillong spoke about importance of Buckwheat 
as a food crop and also its importance in culture. Dr. T. 
Mohapatra spoke on the importance of underutilized 
crops such as Buckwheat in mitigating nutritional inse-
curity of people. Sh. Tathagata Roy, the Hon’ble Gover-
nor of Meghalaya spoke on the importance of buckwheat 
as a food crop and the need to promote its utilization 
by masses. Prof. O. Ohnishi, Emeritus Professor, Kyoto 
University, Japan was conferred "Life time achievement 
award" for his contribution towards buckwheat research. 
Sh. Tathagata Roy, the Hon’ble  Governor of Meghalaya 
presented the award to Prof. Ohnishi. Prof. Dr. Meiliang 
Zhou, of Chinese Academy of Agricultural sciences, Bei-
jing, Dr. Manoj Prasad of NIPGR, New Delhi and Dr. J. 
C. Rana of Bioversity International, New Delhi were 
conferred Golden Peacock Awards during the Inaugural 
function of the Symposium. Dr. Trilochan Mohapatra, 
Secretary (DARE), Ministry of Agriculture Govt. of India 
and DG, ICAR, New Delhi presented the awards to the 
recipients. The organizing committee of the Symposium 
also included Professors and other scientists from NEHU 
and elsewhere in India, Research fellows of School of Life 
Sciences of NEHU and Graduate students of the Depart-
ment of Botany, NEHU. Prof. Nikhil Chrungoo of NEHU 
was elected by IBRA Assembly as Chairman of IBRA for 
the period of the next three years. Poland was by IBRA As-
sembly decided to be the country for organizing the next 
15th International Symposium on Buckwheat in 2022.
27
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