FOLIA BIOLOGICA ET GEOLOGICA 61/1, 7–15, LJUBLJANA 2020 THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA OF EASTERN TIBET AND ITS DIFFUSION TO INDIA AND THE HIMALAYAN HILLS IZVOR GOJENE AJDE NA OBMOČJU DISTRIKTA MANKANG OBMOČJA SANJIANG VZHODNEGA TIBETA IN RAZŠIRITEV V INDIJO TER NA OBMOČJE HIMALAJE Ohmi OHNISHI1 http://dx.doi.org/10.3986/fbg0062 ABSTRACT The origin of cultivated buckwheat in Mankang district of the Sanjiang area of Eastern Tibet and its diffusion to India and the Himalayan hills Natural populations of the wild ancestor of cultivated common buckwheat were searched and collected, starting from its discovery in1990 and finishing the collections in 2005. Among the collections, the samples Zhuka, Xihe from Mankang district of Tibet are most closely related to culti- vated common buckwheat. On the other hand, cultivated populations of common buckwheat in Zhouba, Zhubalong both from Mankang district are most closely related with the wild ancestor of common buckwheat. This leads to the hypothesis on the origin of cultivated buckwheat in Man- kang district in the Sanjiang area. The diffusion route from the original birthplace to India and the Himalayan hills is proposed. Several characteristics of Indian and Himalayan common buckwheat are discussed. A main conclusion of the discussion is that European buckwheat is not of Indian ori- gin nor of the Himalayan origin. It probably came from the northern China through the Silk Road Key words: buckwheat, wild ancestor, origin, diffusion, India, Himalaya, short day plant IZVLEČEK Izvor gojene ajde na območju distrikta Mankang območja Sanjiang Vzhodnega Tibeta in razširitev v Indijo ter na območje Himalaje Iskali in zbirali so naravne populacije divjega prednika gojene navadne ajde, začeli so leta 1990 in zaključili 2005. Med zbranimi vzorci je bil vzorec Zhuka, Xihe iz Mankanga, Tibet, najbolj soroden gojeni navadni ajdi. Po drugi strani, vzorca gojenih ajd iz Zhouba in Zhubalonga, oboje iz Man- kanga, so najbolj sorodni divjemu predniku navadne ajde. Na osnovi tega lahko oblikujemo hipotezo o izvoru gojene ajde v Mankangu na območju Sanjianga. Pot širjenja od pr- votnega izvora v Indijo in na območja gorovja Himalaje je predlagana v tej razpravi. Avtor opisuje lastnosti navadne ajde v Indiji in na območju Himalaje. Glavni zaključek je, da ajda v Evropi ne izvira iz Indije ali z območja Himalaje. Ver- jetno je v Evropo prišla iz Severne Kitajske po Svilni poti. Ključne besede: ajda, divji prednik, izvor, razširjanje, In- dija, Himalaja, rastlina kratkega dne. 1 Professor emeritus of Kyoto University, Jinryo 3-10-3, Ohtsu city, Shiga prefecture 520-2132, Japan, e-mail: Ohmi.Ohnishi@ zd.ztv.ne.jp OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 8 FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 Since the time of de Candolle (1883), (a) what is the wild ancestor of cultivated common buckwheat and (b) where is the original birthplace of cultivated buck- wheat, these two problems have been the main issues to be solved by buckwheat scientists. The wild ancestor of cultivated buckwheat was clarified as F. esculentum ssp. ancestrale Ohnishi, which was first discovered in 1990 in the Wulang river valley in Yongsheng district of Yunnan prov- ince, in China by Ohnishi (1991). As for the birth- place of buckwheat, Ohnishi (2004, 2007, 2010, 2016, and 2018) has repeatedly claimed that the Sanjiang area of Yunnan, Sichuang provinces and east Tibet in China is the original birthplace of cultivated buck- wheat. In the Himalayan countries, India, Nepal, Bhutan, and Pakistan, buckwheat is cultivated extensively and buckwheat is consumed well. Buckwheat in India and the Himalayan hills has some characteristics which are not seen in other regions such as China, Japan and Eu- ropean countries. Today, I discuss the original birthplace of buck- wheat in more details, and I consider the diffusion route from the place of origin to India and to the Him- alayan hills. Finally, I discuss the characteristics of In- dian and the Himalayan buckwheat. As a conclusion, I suggest that the cultivated buckwheat in European countries has never come from India nor from the Himalaya, it probably came from northern China through the Silk Road. 1. INTRODUCTION 2. THE EXACT ORIGINAL BIRTHPLACE OF COMMON BUCKWHEAT The wild ancestor of cultivated common buckwheat was first discovered in Yongsheng district in Yunnan province of China in 1990 (Ohnishi, 1991). Ten-years searches for the wild ancestor in Yunnan and Sichuan provinces, and the searches in Mankang district of eastern Tibet in 2002 and 2004, and finally the search- es in the Tongyi river valley and the Nyiru river valley in 2004 and 2005 clarified the distribution areas of the wild ancestor of common buckwheat (Ohnishi 2007, see also Ohnishi and Tomiyoshi, 2005). Photo 1: Cultivated common buckwheat in Sanjian area (Weixi district, Yunnan provice). Flower color in this area near the original birthplace is beautiful pink. OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 9FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 Photo 2: The wild ancestors growing in the Xihe river valley of Mankang district in eastern Tibet. The wild ancestors in this valley are genetically most closely related with cultivated buckwheat. Hence, the Xihe river valley along with the towns in northern Mankang district are considered as the original birthplace of common buckwheat. Photo 3: The cultivation of common buckwheat in Yanjing town of southern Mankang district. The brown part of the cultivated field is common buckwheat just before harvest. Yanjing town has a good weather condition for buckwheat cultivation and the wild ancestors of commom buckwheat are also growing at the margine of buckwheat fields, although those wild ancestors are not so closely related with cultivated buckwheat. OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 10 FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 The wild ancestor is distributed in 1. The Sanjiang area of Yunnan province and east- ern Tibet, 2. Sporadic distribution in northwestern Yunnan province and southwest corner of Sichuan province, and 3. The Tongyi river valley in Muli district of Si- chuan province and the Nyiru river valley in Shangrila district of Yunnan province. Both the Tongyi river and the Nyiru river are small tributary of the Shuiluo river, a tributary of the Jinshajiang river. Cultivated common buckwheat and wild ancestors are illustrated with Photos 1 – 4. Among the collected wild ancestor populations, the wild ancestors from the Sanjiang area were re- vealed to be the most closely related with cultivated common buckwheat in AFLP variation (Konishi et al., 2005) and allozyme variability (see Figure 1, see Ohni- shi and Nishimoto, 1988, for the procedures of the electrophoresis and the names of enzymes analyzed). A part of the data on the frequencies of allozymes can be found in Ohnishi (2007). The N-J tree of Figure 1 was written following by Saitou and Nei (1987) using PAUP* (Phylogenetic analysis using parsimony) version 4.0 (Swofford, 1990, 2002). The wild ancestors in the Tongyi river valley and the Nyiru river valley are highly variable in AFLP and allozymes, however, the populations from those val- leys are most distantly related with cultivated popula- tions of common buckwheat. The sporadically distrib- uted ancestral populations in Yunnan and Sichuan provinces showed intermediate closeness to cultivated buckwheat (Fig. 1). This may leads to the conclusion that the Sanjiang area is the original birthplace of common buckwheat. Konishi and Ohnishi (2007) showed that close genetic relationship between the wild ancestor in the Sanjiang area and cultivated populations is not due to recent hy- bridization between them. Now, by observing Fig. 1 more carefully, you may find that the Zhuka population and the Xihe popula- tion from Mankang district are most closely related with cultivated populations. The Adong population (in Yunnan province) and the Yanjing population (close to the border between Yunnan and Tibet, see Fig. 2) are both from the Sanjiang area, but they are slightly far away from the cultivated populations as compared with the Zhuka and the Xihe popultions (Fig. 1). Furthermore, by observing Fig. 1 from the culti- vated population side, you may find that the cultivated populations of Zhubalong and Zhouba (both come from northern Mankang district) are closely related with the wild ancestor of cultivated buckwheat (Figs. 1 and 2). Now, as a conclusion, we can say that the Yunnan part of the Sanjiang area is not involved in the origin of buckwheat cultivation, rather, Mankang district of the Photo 4: The landscape of northern Mankang district. Although this area is believed to be the original birthplace of common buckwheat, barley is mainly cultivated in cultivation fields. OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 11FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 Sanjiang area, particularly, north part of Mankang dis- trict is the original birthplace of cultivated buckwheat. So, it is reasonable that Wang (1986) reported archaeo- logical remains (buckwheat seed grains) in the archaeo- Figure 1: The N-J tree among the populations of wild ancestor and cultivated populations of buckwheat based on allozyme data. The name of locations written in Chinese letters in the figure should be expressed in pinyin as is shown in parentheses. Only the locations appeared in text are listed bellow. 西河(Xihe) 竹卡(Zheke) 阿東(Adong) 塩井(Yanjing) 博科(Boke) 塩源(Yanyuang) 金安(Jinan) 永勝(Yongsheng) 尼通(Nidong) 東義(Tongyi) 依吉(Yiqi) 竹巴龍(Zhebalong) 巴塘(Batang) 肋巴(Zhouba) logical site of Karuo village near Chamdu of east Tibet. This site is close to the original birthplace Mankang dis- trict of eastern Tibet (see Fig. 3).. 3. DIFFUSION OF CULTIVATED BUCKWHEAT TO INDIA AND THE HIMALAYAN HILLS Cultivated common buckwheat migrated from its orig- inal birthplace, the Sanjiang area of southwestern China to northern China first, then to the Korean pen- insula and Japanese islands (Murai and Ohnishi, 1996). From northern China, cultivated buckwheat mi- grated west, to the central Asian countries, then to Eu- ropean countries through the Silk Road as I discussed in the previous 13th International Symposium on Buckwheat (Ohnishi, 2016). From the original birthplace of common buck- wheat, Mankang district, cultivated buckwheat first went west (Murai and Ohnishi, 1996), overcoming high mountains, the Hengdan mountains, in the three- river region (the Sanjiang area), and entered to the Yaruzanpu river basin, then finally arrived at Bhutan, Sikkim, Nepal and India. There exists only one route connecting Mankang district in the Sanjian area and the Yaruzampu basin in Tibet as seen in Fig. 3. After OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 12 FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 Figure 2. Distribution of the wild ancestor of cultivated common buckwheat in Mankang district of the Sanjiang area. : village or town where the wild ancestor was found. Northern population such as Zhouba, Zhuka and Xihe are close to cultivated populations (Fig. 1) OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 13FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 arriving these countries, it is easy for buckwheat to travel further west along the Himalayan hills, because the Himalayan hills may provide a comfortable culti- vated conditions for cultivated buckwheat. Only a few crops diffused through the same route as buckwheat. Tea plant, Camellia sinensis, originated in Yunnan province in China, diffused through the same route as common buckwheat, became an impor- tant cultivated plant in India and the Himalayan hills. Only the crop diffused opposite direction from the Himalayan hills to the Sanjiang area is the finger mil- let (Eleusine coracana), originated in Africa. It arrived at the Indian subcontinent, India and Pakistan. Then it diffused to southern China, through the same route as of buckwheat, but in the opposite direction (Hoshi- kawa, 1992). Figure 3. Diffusion route of cultivated buckwheat from Mankang district in the Sanjiang area to India and the Himalayan hills. As shown in Fig. 3, the Karuo archaeological site, from where the oldest buckwheat seed grains were report- ed, is located not so far away from the original birthplace of cultivated buckwheat. Along the diffusion route, wild perennial buckwheat, F. cymosum ssp. pillus (syn. Fago- pyrum pillus Chen, see Chen, 1999) and a weed species F. gracilipes are found, near to Dongmai village, Bomi dis- trict of Tibet, and Paro of Bhutan, respectively (Fig. 3). It is well-known that F. cymosum growing in the west of the Yaruzampu grand canyon is all tetraploid, and is often called F. dibotris in Nepal and India (see Hara, 1972). OHMI OHNISHI: THE ORIGIN OF CULTIVATED BUCKWHEAT IN MANKANG DISTRICT OF THE SANJIANG AREA 14 FOLIA BIOLOGICA ET GEOLOGICA 61/1 – 2020 Here, I mention several characteristics of buckwheat and buckwheat cultivation in India and the Himalayan hills. 4.1. Buckwheat cultivation as a fresh vegetable in India Both common buckwheat and Tartary buckwheat are cultivated as a fresh vegetable in India, rather than as a grain crop. As a result of long history of cultivation as a fresh vegetable, local varieties for such purpose have become the varieties with very small grains. I observed such a small grain variety in Bageshwar town, the state of Uttar Pradesh, west India. This custom of buck- wheat use as a fresh vegetable is found both in eastern India and western India. 4.2. Common buckwheat in India and in the Himalayan hills is a short day-length plant Common buckwheat in India and in the Himalayan hills is usually cultivated in fall to early winter, from September to December. As a result of cultivation under the condition of mild temperature and of short day-length, buckwheat in India and the Himalayan hills have become short day-length plant, with charac- teristics of tall vigorous vegetable parts with relatively longer cultivation period as compared with buckwheat from northern China and Japan. 4. CHARACTERISTICS OF BUCKWHEAT IN INDIA AND IN THE HIMALAYAN HILLS European common buckwheat has the character- istics of long-day to neutral day-length plant as the de- scendants of diffused buckwheat through the Silk Road (Ohnishi, 1993, 2016). The characteristics of buckwheat in the Himalayan hills, short-day plant, is opposite to the characteristics of European buckwheat, day-neutral to long day-length plant. This leads to the conclusion that European buckwheat does not have the origin in India nor in the Himalayan hills. 4.3. Making buckwheat noodle by hands in Ladakh of India Buckwheat noodle was not developed well in Nepal, India, and Pakistan. Two methods of making buckwheat noodle (Ohni- shi, 2016), one using a noodle making wooden equip- ment, I call this as a Chinese method, one using special cooking knife to cut and make fine noodle of buck- wheat dough, I call this as a Japanese method. Neither methods diffused to Nepal and India. In Bhutan a buckwheat noodle making equipment, called Putta in Bhutan, is used, hence buckwheat noodle is served as a daily food. If peoples know neither methods, what happens for them? 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