Effect of the Management of Seed Flows And

Agric Hum Values DOI 10.1007/s10460-015-9646-3

Effect of the management of seed ﬂows and mode of propagation on the genetic diversity in an Andean farming system: the case of oca (Oxalis tuberosa Mol.)

1 1 2 1 Maxime Bonnave • Thomas Bleeckx • Franz Terrazas • Pierre Bertin

Accepted: 3 August 2015 Ó Springer Science+Business Media Dordrecht 2015

Abstract The seed system is a major component of tra- cash and self-consumption landraces. Cash landraces were ditional management of crop genetic diversity in developing intensively exchanged; self-consumption landraces were countries. Seed flows are an important part of this system. isolated at the farmer level and prone to genetic drift and They have been poorly studied for minor Andean crops, complete loss. Merchants exported seeds of cash landraces especially those that are propagated vegetatively. We across Bolivia and into Peru and Argentina. New sexually examine the seed exchanges of Oxalis tuberosa Mol. (oca), a produced genotypes are less incorporated into cash landraces vegetatively propagated crop capable of sexual reproduc- than in self-consumed landraces. However, new genotypes tion. We studied the seed exchanges of four rural commu- incorporated into cash landraces are diffused faster and nities in Candelaria district (Cochabamba department, better, being more intensively exchanged. We propose Bolivia) at the international and local levels, emphasizing conservation strategies that can be applied to other vegeta- the spread of new sexually-produced genotypes through tively propagated and minor Andean crops. these exchanges. Interviews with 44 farmers generated socioeconomic, agronomic, crop diversity and seed Keywords Landrace diversity Á Minor crop Á Propagation exchange information, and data on the potential incorpora- mode Á Seed exchange Á Andes Á Wealth tion of new sexually-produced genotypes in the crop germplasm. We interviewed merchants to evaluate the input and output of genetic diversity in the communities studied. Introduction Results showed a positive effect of the farmers’ wealth on the diversity cultivated and on seed exchanges. Most seed Traditional management of crops is still practiced by a exchanges occurred at market, creating a distinction between large proportion of the world’s farmers, especially in developing countries. Those traditional practices, considered to be the most fragile components of the agrarian & Maxime Bonnave systems, have a major influence on evolution processes and [email protected] the genetic diversity of crops (Vigouroux et al. 2011). In Thomas Bleeckx these systems, almost every farming practice results in an [email protected] effect on the global genetic diversity of crops. Franz Terrazas Oca is a clonally propagated tuber crop cultivated [email protected] mainly in the Andes. Consumed as a part of the local staple Pierre Bertin diet, oca follows potato, the main crop, in the agricultural [email protected] rotation and plays an important role in interfering in the life cycle of potato pests (Terrazas and Valdivia 1998). At the 1 Earth and Life Institute, Universite´ catholique de Louvain, Croix du Sud 2 – 11 (L7.05.11), 1348 Louvain-la-Neuve, difference of potato, oca cultivation has not spread Belgium worldwide and has not been the subject of intensive sci- 2 Fundacioń PROINPA (Promocioń e Investigaciońde entific research. To our knowledge, no plant breeding Productos Andinos), Cochabamba, Bolivia programs have been conducted for this crop. 123 M. Bonnave et al.

Similarly to the other tuber crops domesticated in the Seed exchanges are of crucial importance on the Andes (potato, mashua—Tropaeolum tuberosum R. & P.— dynamic conservation of genetic resources (Pautasso et al. and ulluco—Ullucus tuberosus C.), oca shows an important 2012). They have been very few studied for oca. However, intraspecific phenotypic variability and genetic diversity a well-developed literature is available for other Andean (Pissard et al. 2006, 2008a; Malice et al. 2009; de Haan tuber crops, especially for potato. Most farmers obtain their 2009). Moreover, studies demonstrated the existence of an tuber seeds by producing them. However, farmers usually intra-landrace diversity, genetically and/or phenotypically, replace their tuber seeds every 4–6 years, when seeds are for various landraces (Emshwiller 2006; Pissard et al. ‘tired’, which means that they observe a decrease in yield 2008b; Bonnave et al. 2014). Such phenomenon, along or vigor, probably due to pathogen accumulation (Bianco with an inconstancy of the folk naming system, has also and Sachs 1997; Zeven 1999; Ramirez 2002; Garcıá and been observed in the Andes for potato (Quiros et al. 1990). Cadima 2003). In the case of potato, a formal seed system As farmers use very few morphological criteria (mainly exists, providing farmers with quality controlled seeds, based on the tuber color, shape and taste) to name their although it only covers 5 % of the potato seed demand in landraces, confusion between different genotypes can the Andes (Thiele 1998; Ezeta 2001). For the other Andean occur. When obtaining a genotype they do not own, tuber crop (oca, mashua and ulluco) such system does not farmers can therefore incorporate it in a morphologically exist. Therefore, a vast majority of Andean tuber seeds are similar landrace, therefore creating intra-landrace diversity. obtained by informal sources such as direct exchanges Farmers usually obtain these genotypes from seed between families in the same community, local markets, exchanges. However, sexual reproduction or mutation agricultural fairs, traditional seed routes passing by villages accumulation may also be the source of new genotypes. recognized for their seed production or during celebrations. Oca has a fully functional sexual reproduction system Seeds can be purchased or obtained by traditional methods (Trognitz et al. 1998) and sexual reproduction leading to such as barter, gift, loan or inheritance, and as a payment productive plants has been observed in Bolivia in field for work or by collaborative work (production is split conditions. Moreover, surveys showed that an incorpora- between a farmer who supplied seeds and another who tion of sexually produced genotypes into the cultivated supplied land) (Brush et al. 1981; Thiele 1998; Garcıá and germplasm was highly probable, although unconsciously Cadima 2003). Zimmerer (2002) showed that farmers tend realized by the farmers. This incorporation would take to acquire new seeds from extracommunity sources and place when, to replenish seed stocks, farmers would gather that seeds flows are not circumscribed at the household and tubers of k’ipas. K’ipa is a quechua term meaning volun- community level. Ramirez (2002) observed that in Peru teer plants of a crop species emerging in sites of former farmers used oca seeds coming from production sites sit- fields in the years following cultivation of this crop. It uated 80 km away. According to Espinoza (1998), seeds should not be confused with k’ita, which is the quechua can be distributed across the country via the markets of the term for wild relatives. At this moment, tubers arising from big cities. Finally, Andean tubers seeds flows take place vegetative propagation of the landraces previously culti- within and among the different agroecological habitats vated in these fields and tubers arising from recent sexually where they are cultivated, especially among different alti- produced genotypes would be mixed up because of the tudinal levels (farmers sow seeds that are considered very few morphological criteria used to differentiate lan- ‘‘tired’’ at higher altitude and then bring them down again) draces (Bonnave et al. 2014). Brush et al. (1981) and Johns (Brush et al. 1981; Thiele 1998; Zimmerer 2002; Terrazas and Keens (1986) made a similar hypothesis on the use of and Valdivia 1998). potato k’ipas in Bolivia. Moreover, Quiros et al. (1992) A decrease in the number of oca landraces cultivated by observed active incorporations of sexually-produced new farmers (provoking irreparable genotypic erosion) has been potato genotypes in Peru. Farmers would collect botanical described in the literature for communities in Bolivia, Peru seeds, sow them in beds and carry out a selection of the and Ecuador (Bianco and Sachs 1997; Tapia and Estrella best new landraces based on the size, number and quality 2001; Garcıá and Cadima 2003). The causes of this erosion of the tubers. Similarly, cassava (Manihot esculenta C.) could be diverse, including: the increasing linkage of farmers in Guyana actively seek volunteer plants arising production to the market, which demands only a few uni- from sexual reproduction and take care of these plants until form varieties; loss of traditional knowledge and familiar maturity. When they are judged satisfactory, these new germplasm because of rural exodus; decreasing demand in genotypes are multiplied as a new landrace or assigned to cities from the poor social prestige of consuming oca; and a an existing landrace (Elias et al. 2001). For more infor- rise in pests and diseases (Terrazas and Valdivia 1998; mation on mixed clonal/sexual systems, we invite the Huamań 2001). reader to consult the extensive literature review by McKey This study approaches the landrace diversity, the seed et al. (2010). exchanges and the management of sexually produced new 123 Effect of the management of seed flows and mode of propagation on the genetic diversity in an… genotypes of oca in four semi-traditional communities of The entire region, considered as a microcenter of bio- Bolivia in order to gain a better understanding of the diversity for Andean tubers, presents ideal climatic and dynamics influencing landrace/genotypic diversity at the pedagogical conditions for their production. However, as community level (the studied communities can not be for all mountainous areas, heterogeneity is observed in considered as fully traditional as they are highly influenced altitude, climatic conditions and soil composition, which by the nearby Colomi market, which involves modern creates diversity in the agricultural practices and cultivated socioeconomic actors and modern transportation routes). varieties inside the small district of Candelaria. Terrazas Although similar researches have been conducted for and Valdivia (1998) and Garcıá and Cadima (2003) rec- potato, an economically important crop that benefits of a ognized three different agro-ecological zones in Candelaria lot of institutional support and research, this research is (Table 1). novel as it approaches the management of the landrace diversity of a subsistence minor crop and its relation to the Interviews with farmers market. Moreover, it is the first time that seed exchanges and the management of sexually-produced new genotypes Sample selection are considered together. The principal research questions are: We selected four communities (Chimpa Rancho, Chull- (i) Is the management of landrace diversity and seed pani, Piurata and Pico Central; Fig. 1) because of their flows linked to socio-economic criteria such as agro-ecological zone [following the hypothesis of Terrazas wealth? and Valdivia (1998) that agricultural practices and seed (ii) What is the relative importance of the market and management vary between zones] and their tradition of of traditional direct exchanges in the seed supply cultivating oca. For each community, the isolation from the and demand and what are the origins and desti- market was estimated and the number of inhabited houses nations of seeds flows? was assessed by field observations, discussions with the (iii) Do farmers incorporate sexually-produced new community leader and observation of satellite images genotypes into their landraces and are those new (Table 2). A total of 44 interviews (35 men and 9 women) genotypes included into the seed exchange mech- were conducted. At least 28 % of the inhabitants of each anisms and therefore distributed to other farmers? community were interviewed. As no detailed list of inhabitants was available, the farmers interviewed could The answer to these questions would permit to identify not be selected randomly and, as proposed by Almekinders key actors and processes of the management of genetic and Louwaars (1999), one of every four or five houses was resources of minor vegetatively propagated crops. This selected, taking care to choose a geographically represen- would allow the creation of more efficient in situ conser- tative sample in order to cover the different agro-ecological vation programs by targeting these key actors and by zones. considering these processes, which is vital in order to halt genetic erosion of theses crops. Interviews

Materials and methods We conducted all interviews in Quechua, the local native language, and recorded them for later consultation. The ﬁrst Context part of the interviews aimed to gather socioeconomic and general agronomic information as well as data relative to This study took place between January and May 2013 in oca crop diversity and seed exchanges (sales and acquisi- the district of Candelaria (17.27S, 65.92W, 3300 m), tions). To obtain information that was easy to compare municipality of Colomi, province of Chapare, department between farmers and suitable for statistics, this ﬁrst part was of Cochabamba, Bolivia (Fig. 1). The district is geo- conducted as a structured interview. Such interviews are graphically organized into communities, each from 50 to adapted to the collection of precise data that cannot be 500 persons, all depending on agricultural incomes. The misinterpreted. On the contrary of a simple questionnaire, Human Development Index of Colomi is of 0.42, which is they offer the interviewer the opportunity to reformulate, low compared with all Bolivia (0.675) (PRODISEC 2002; explain and deepen the questions (Bernard 2006). UNDP 2013). The principal commercial node is the The second part of the interviews aimed to obtain Colomi market, which is ideally situated on the Cocha- information about the management of k’ipas and was bamba-Santa Cruz national road. conducted as a semi-structured interview, with open

123 M. Bonnave et al.

Fig. 1 Map of the four communities studied, with the location of the homes of the 44 farmers interviewed and of the Colomi market. Datum = WGS 84. Projection = Mercator Auxiliary Sphere. Data source: www.diva.gis.org, ESRI topographic layer questions on the thematic, to allow the farmers to share sexually-produced genotypes could be incorporated into their knowledge more freely and avoiding a bias due to the the cultivated landraces. expectations of the interviewers. This method is more suitable in explaining and demonstrating the complexity of Data analysis the subject and understanding the nature and foundation of the observed variability (Almekinders and Louwaars 1999; We constructed a grid encoded into a database to encom- Bernard 2006). Information was gathered on the knowl- pass all the information from the structured part of the edge of the existence of k’ipas, their use (speciﬁcally their interviews, and carefully and completely analyzed all the use as seeds) and management in order to assess if records. The analysis of the semi-structured interviews 123 Effect of the management of seed ﬂows and mode of propagation on the genetic diversity in an…

Table 1 Altitude, environmental conditions, main rotation, other crops and fallow period of the three agro-ecological zones of Candelaria (Terrazas and Valdivia 1998; Garcı´a and Cadima 2003) Lower zone or Pampa Intermediary zone or Ladera Higher zone or Puna

Altitude (m) 3000–3350 3350–3650 3650–4100 Environmental conditions Temperate Temperate to cold Cold Humid Humid Highly humid Low slopes (\10 %) Medium to high slopes (20–70%) Low slopes \20 % Main rotation Potato (commercial and Potato (traditional, commercial Potato (traditional and improved varieties)a and improved varieties) commercial varieties) Oca and/or faba beansa Oca and/or faba beans Oats Oats or barleya Ulluco and/or faba beans Oats Other crops Tarwi, Isanõ and Ullucoa Tarwi, Isanõ and Ulluco Oca and Ulluco Fallow period 1–3 years 3–4 years 10–15 years a Latin names: Potato (Solanum tuberosum L., Solanum phureja J. & B), faba beans (Vicia faba L.), Oats (Avena sativa L.), barley (Hordeum vulgare L.), Tarwi (Lupinus mutabilis S.), Isanõ(Tropaeolum tuberosum R. & P.), Ulluco (Ullucus tuberosus C.)

Table 2 For each community: latitude and longitude of the geographical center, agro-ecological zones cultivated, number of inhabited houses and number of interviews realized and percentage of households interviewed Community Lat. (°) Long. (°) Agro-ecological Households Interviews % Households zones realized interviewed

Chimpa Rancho 17.26 65.92 Pampa 58 16 28 Ladera Chullpani 17.23 65.94 Pampa 36 12 32 Ladera Pico Central 17.32 65.96 Ladera 18 6 33 Punta Piurata 17.25 65.96 Ladera 18 10 56

followed three steps: (1) ten randomly selected interviews (E), which reﬂects how close in proportion each landraces were fully transcribed and translated; (2) a thorough are. Evenness was calculated according to the formula: examination of the transcripts permitted the creation of a E ¼ H0= ln S grid containing all pertinent information; and (3) we lis- tened to the 34 other interviews and encoded them into the where H0 is the Shannon index and S refers to the number grid. of landraces present in a given community. High evenness

The richness of a landrace i (ni) is equal to the number therefore results from landraces having equal abundances of farms where it is cultivated and was determined in each (Tamiru Oli 2006). community. Landrace diversity data was analyzed with the Several pertinent categorization criteria were defined to Shannon diversity index (H0), which takes into account the analyze the results: sex, age, community, agro-ecological proportional abundance of landraces, according to the zone, wealth, number of cultivated varieties and total formula: production of oca. The categorization of agro-ecological XS zones could not be based on the communities because 0 H ¼À pi ln pi farmers in the same community could possess fields at i¼1 different altitudes. Therefore, each farmer was asked at which zones he owned fields, was attributed a corre- where p is the frequency of landrace i (n /N, where N is the i i sponding value to allow calculations of means and was sum of the number of farms where individual landraces categorized into one of the three agro-ecological zones were found) and S is the number of landraces. Shannon (Table 3). The wealth categorization was realized using the diversity index increases both with richness and evenness

123 M. Bonnave et al.

Table 3 Categorization of Agro-ecological zone Attributed value Agro-ecological zone of farmers into an agro-ecological attributed to farmers ﬁelds owned by farmers zone and attributed value based on the agro-ecological zones of Pampa 1 Pampa the ﬁelds owned. Ladera baja and ladera alta mean low and 2 Pampa and ladera baja high altitude slope, respectively Ladera 3 Ladera baja 4 Ladera baja and ladera alta Puna 5 Ladera alta and/or puna

method described by Bianco and Sachs (1997) for six sell their production and where a large proportion of them criteria. For each criterion, a specific value was attributed buy seeds if necessary. The interviews were structured, to whether the farmer was above or under the average level of be short and precise, as merchants had little time to allow to the criterion (Table 4). Among the other services they interviewers. Ten interviews were held in April–May 2013, provide, cattle are often considered as a store of wealth in at the time of the harvest, when merchants (only women) traditional agriculture. The livestock index criterion rep- buy oca from the farmers. The goal of these interviews was resents the ‘cost equivalence’ of the total livestock owned, to determine if and how seeds produced in Candelaria could calculated by summing the relative cost at the market in be distributed to other parts of the province/depart- Colomi (considering the cost of a cow as a basic unit) of ment/country. The merchants were also asked if they sold each owned animal (pork = 0.4; sheep = 0.2; seeds in Colomi and where those seeds came from. The horse = 1.5). The sum of the six values provided the answers to that question were highly imprecise because they wealth index. Farmers with a wealth index \5 were con- usually sold seeds to the farmers in August or September; sidered as poor (39 % of farmers), those with an index [6 that is, during the sowing period. Another set of ten inter- as rich (14 %) and those in between (5 or 6) as interme- views was held in September. Merchants were only asked diary (48 %). These proportions are similar to those where they came from, what were the landraces of the seeds observed by Garcıá and Cadima (2003) in the same region. they were selling and where those seeds came from. All Simple descriptive statistics were used to compare the interviews were transcribed and translated. Quantitative and different groups of farmers and their behavior. Correlation qualitative data were obtained from those transcriptions and paired t test, ANOVAs and HSD Tukey–Kramer tests were analyzed with simple descriptive statistics. used to test the relations between variables. Contingency tables were realized to test the effect of category variables. All tests were realized with R software (R Core Team Results 2013), JMPÒ (SAS Institute, Cary, NC, USA) and ExcelÒ (Microsoft, Redmond, WA, USA). Socioeconomic and agronomic profiles

Market interviews The average age of the farmers we interviewed was 50 years, their families averaged ﬁve members and the We interviewed merchants from the market at Colomi, near average size of their farms was 3.55 ha. The average Candelaria, where almost all the farmers we interviewed wealth index was 1.99. Community membership did not

Table 4 Mean, range and Criteria Mean Range Attributed value attributed value for each criterion used tocategorize the Farm size (ha) 3.16 0.5–16 0 or 1a wealth of farmers interviewed Family size 5.08 1–11 0 or 1a Potato production (bags) 79.21 16–200 0 or 1a Oca production (bags) 31.61 2–100 0 or 1a Livestock index 6.37 0–17 0 or 1a Employment of day laborers (False or True) 0 or 1b a Below or above average value of the criterion, respectively b False or True, respectively

123 Effect of the management of seed flows and mode of propagation on the genetic diversity in an… affect those four variables. Almost all farmers had not intended for the market, although also often consumed by finished grade school. households, whereas self-consumption landraces were The crop rotations and fallow periods observed in the only intended for family consumption. The proportion of communities were consistent with the usual rotations for farmers growing cash landraces was far more significant the agro-ecological zone cultivated by these communities than the proportion of farmers growing self-consumption (Table 2). The exceptions were almost all the farmers in landraces in all communities studied (Table 5a, b, c). All Chimpa Rancho, and half of the farmers of Chullpani, who farmers cultivated at least one or two cash landraces had stopped to practice fallow periods. Information about while only one-third cultivated self-consumption lan- the reasons for the interruption of this practice was not draces. All communities cultivated the same pool of cash collected. More than 70 % of the farmers employed daily landraces (in different proportions) while the pools of workers except in Pico Central, where only 33 % employed self-consumption landraces varied between communities. daily workers. Eighty percent of the farmers paid for labor The average number of self-consumed landraces per farm exclusively in cash, and 20 % paid with seeds or cash. The was 0.43 while the average number of cash landraces per ayni (an informal system where two farmers agree to work farm was 2.43. The most widespread landraces where on each other’s farm) was occasionally practiced by 75 % Senõra and Kayara and were cultivated by respectively 68 of all interviewed farmers. Farmers owned an average of and 65 % of the farmers. The Shannon diversity index five potato varieties and the average potato production was was considerably lower for self-consumed than for cash 79.21 bags (range 16–200 bags). landraces while, on the contrary, the evenness was higher for self-consumed than for cash landraces. This indicates Oca production and landrace diversity that, although better distributed among farmers, self-consumed landraces have a very low richness. The Pico The average production of oca was 32 bags (approximately Central community, which is the smallest community, is 100 kg each) with a minimum of 2 bags and a maximum of also the community managing less diversity, both for cash 100 bags. The average yield was 13 bags harvested per sown and self-consumed landraces. bag (range 4.6–25). No statically significant effect of the community was found. The total production per farmer was positively correlated (0.38) to yield (in bags harvested per Farmers’ seed exchanges sown bags) (p = 0.0104). Farmers intended that 82 % of their production should be for sale, 9 % for self-consumption Farmers’ seed sales and 9 % for seed stock renewal. All farmers declared that they sold their production at the Colomi market because of Sixty percent of the farmers sold seeds; of these farmers, the good prices that could be obtained and because of its half of them sold every year and the other half sold from proximity. Three farmers also declared that they occasion- time to time. Sales were made in different proportions (i) in ally sold their production to more distant markets (Punata, the market of Colomi, (ii) directly to neighbors or (iii) to Tiraque and Sacaba, which are 50, 20 and 34 km further the members of other communities (Fig. 2). Frequencies of away than Colomi, respectively). One farmer reported that sales varied for each of those contexts; farmers who sold he sometimes rented a truck with other farmers to sell his seeds to the market tended to do it every year (70 % of production directly in La Paz (distance = 420 km). them) and farmers who sold seeds to neighbors or other A total of 11 different landraces were cultivated in the communities tended to do it only from time to time (62 % four communities and each farmer possessed an average of of them). Only two farmers sold seeds in markets other 2.86 landraces. Total production per farmer was positively than Colomi (Punata and Sacaba). Ten farmers sometimes correlated (0.40) to the number of landraces owned (precise frequency was not obtained) sold seeds in small (p = 0.0073). A correlation of 0.42 was observed between quantities at the annual agricultural fair in Candelaria or the number of cultivated landraces and the sown quantity Colomi, mostly to farmers of other valleys who came (p = 0.0048). Likewise, a correlation of 0.39 was observed especially to buy seeds. When asked specifically about between the number of cultivated landraces and wealth exceptions, some farmers who first declared that they did (p = 0.0091). However, although these parameters were not sell seeds finally said that they sometimes did, but only taken into account when calculating the farmers wealth, no when a special demand was made by another farmer. correlation was observed neither between farm size nor Farmers who sold seeds were wealthier (average of 2.31) daily workers employment on the one hand and landrace than farmers who did not sell some seeds (average of 1.47, diversity on the second hand. p = 0.0199). Farmers who sold seeds had a higher total Farmers made a distinction between cash and self- production (average of 43 bags) than those who did not sell consumption landraces. Cash landraces were mostly seeds (average of 20 bags, p = 0.0058). 123 M. Bonnave et al.

Table 5 a: Diversity of self-consumed (SC) landraces in each community, b: Diversity of cash (C) landraces in each community, c: Diversity of landraces in each community a Community Richness among interviewed farmers Proportion of Shannon Evenness Mean farmers cultivating diversity number of Kellu Lluchu Zapallo Pukan˜awi Bola Sauciri SC landraces index landraces/farm chun˜o Kellu kamusa

Chimpa Rancho 4 2 1 1 0 2 0.38 1.47 0.64 0.43 Chullpani 0 0 2 0 1 0 0.42 0.63 0.57 0.45 Pico Central 1 2 0 0 0 0 0.17 0.63 0.57 0.16 Piurata 1 0 0 2 0 0 0.40 0.63 0.57 0.5 Total 6 4 3 3 1 2 0.36 1.66 0.56 0.43 b Community Richness among interviewed farmers Proportion of farmers Shannon Evenness Mean number of cultivating C landrace diversity index landraces/farm Sen˜ora Kayara Kamusa Titicoma Yuraq

Chimpa Rancho 12 8 6 6 7 0.88 1.57 0.43 2.15 Chullpani 9 11 7 5 3 1 1.53 0.43 2.66 Pico Central 1 5 3 3 0 1 1.26 0.5 2 Piurata 8 5 3 3 2 1 1.48 0.48 2.9 Total 30 29 19 17 12 0.95 1.55 0.33 2.43 c Community Proportion of farmers Shannon diversity Evenness Mean number of cultivating both types index landraces/farm of landraces c Chimpa Rancho 0.31 2.05 0.52 2.56 Chullpani 0.42 1.72 0.47 3.16 Pico Central 0.17 1.63 0.60 2 Piurata 0.4 1.75 0.55 2.9 Total 0.31 1.99 0.41 2.86

Farmers’ seed purchases seeds transactions were monetary; six farmers still used barter. It was also still possible to obtain seeds as a pay- Of the 73 % of the farmers who purchased seeds, 60 % ment for harvest labor. Finally, 75 % of the farmers of the purchased every 2 or 3 years and the other 40 % some- intermediary wealth class only acquired seeds at the mar- times or rarely. The 27 % of the farmers who did not renew ket, while 66 % of the rich farmers also acquired seeds their seed stock explained that they did not need to, their through neighbors or other communities. yield being stable over time. Farmers who did not renew The farmers seemed to pay special attention to the origin their stock did not have statistically different yields (in of the seeds bought at the market, to avoid buying seeds bags harvested per bags sown) from those who renewed originating from their own community. For the same rea- their seed stock. The percentage of farmers who did not son, two farmers explained that they did not buy seeds from renew their seed stock varied between wealth categories the Colomi market and preferred to visit other markets. (47, 15 and 0 % of the poor, intermediary and rich farmers, Farmers declared that they acquired new seeds because respectively). Moreover, rich farmers renewed their seed seeds tend to get ‘tired’ over the years, which meant that stock more frequently (67 % of them did so every they observed a yield decrease. A few explained this 2–3 years) than the poor farmers (35 %). Seed purchases decrease by citing an accumulation of diseases and insect were made in different proportions at the market, to pests. It seemed that catastrophic climatic events (mostly neighbors or to members of other communities (Fig. 2). frost and hail) did not particularly affect the oca seed There was no formal seed supply available. Almost all system. Only three farmers had to buy seeds after such

123 Effect of the management of seed ﬂows and mode of propagation on the genetic diversity in an…

Fig. 2 Seed exchange system in the four communities studied events. The other farmers declared that seed production was them ascribed this to the cultivation of different landraces in always ensured because oca is a resistant plant. Moreover, the field, at the same moment or from one year to another. farmers usually cultivated several fields in different places, One farmer explained that when k’ipas grow during a few and these were never subject to catastrophic events at the consecutive years in a field, tubers of colors that do not same time. The new seeds were almost always varieties that correspond to cultivated landraces could be observed. the farmers owned or used to own. Only four farmers Half of the farmers systematically weeded out the k’ipas sometimes tried out a new variety. Farmers sowed the new in cultivated fields because they compete with the culti- seeds apart from those they produced to compare yields. The vated crop, disturb fieldwork and can spread diseases. The best seeds were then kept for the following growing season. other half let them grow to maturity. In both cases, farmers Finally, all farmers owning fields at different altitudes always used the tubers. One-third of the farmers only used them observed an altitudinal rotation to obtain higher yields: seeds for feeding pigs. The other two-thirds used the tubers for from a cultivar cultivated at one agro-ecological zone would self-consumption, sales or as seeds, in different proportion always be sown at another one the next year. and at different frequencies (Fig. 3). Farmers sold k’ipas tubers when they produced some in large quantities or Management of k’ipas when they had unforeseen need for cash. Old farmers were more prone to sell k’ipas tubers (C60 years old; 78 % of All farmers knew that k’ipas can grow in fields previously them) than young farmers (\45 years old; 45 % of them). cultivated with oca and thought that they only originated Richer farmers were more prone to sell k’ipas tubers (83 % from tubers. Two-thirds of the farmers affirmed that k’ipas of them) than poorer farmers (46 % of them); and k’ipas can grow in any crop cultivated after oca (oats, fava bean tubers were sold by 67 % of the farmers owning three or ulluco). The remaining one-third of the farmers found landraces or fewer, and by 38 % of those owning more than k’ipas to be less encountered in oat fields because of the three landraces. shadow created by this crop. For 50 % of the farmers, Half of the farmers did not use k’ipas tubers as seeds k’ipas could be found in fields from 1 year to more than because they have low yields, transmit diseases or because 5 years after cultivation. They explained that the k’ipas they never thought about it. One of the farmers explained population may increase year after year, especially when that he did not use k’ipas as seeds because they ‘change fields are cultivated without interruption. On the contrary a color’. Farmers used k’ipas tubers as seeds when they fallow period of a few years makes k’ipas disappear. lacked seeds at the moment of sowing (poor calculation of K’ipas with different morphologic characteristics were seed quantities or poor production during the previous observed in the same field by 66 % of the farmers. Most of year) or when they mixed the harvested k’ipas tubers with

123 M. Bonnave et al. their regular harvest and therefore could not differentiate them markets of Cochabamba, El Alto and Oruro. Two of the from each other. Farmers always assigned the k’ipas tubers to merchants were retailers and sold direct to consumers. The a previously owned landrace on the basis of the color and the others were wholesalers and sold to other merchants or shape of the tuber, and gave them the same name. They never retailers, who then sold the merchandise in the cities that gave new names to varieties presenting different colors or depended on those large markets (Fig. 4). Two of the tuber shapes. Apparently the culinary characteristics of the wholesalers explained that they sometimes sold to Peruvian tubers, which are very important in traditional landrace clas- or Argentinian merchants, who then imported the mer- sification, were not determined at the time of harvest. Almost chandise into their countries. Merchants were not willing to all farmers made no distinction between normal seeds and share quantitative data on the volumes of merchandises k’ipas seeds, and mixed them in the same field. However, they managed because of important competition between three farmers sowed k’ipas seeds separately from normal themselves. seeds to assess the performances of both types of seeds and Seven out of ten merchants also bought tuber seeds. kept the best one for the following year. Seeds are smaller than consumption tubers; they are oval and not washed by farmers. Half of the merchants bought The market as a seed exchange platform the seeds at harvest time and stocked them until the sowing period. The other half bought them at sowing time and sold At harvest time directly to producers. Merchants sold the seeds in the same places where they sold consumption tubers. Very little The Colomi market merchants interviewed at the time of information could be gathered on the provenance of the harvest presented diverse profiles. All except one (who seeds sold to the Colomi farmers. Four merchants said that came from La Paz) came from Colomi (four) or Cocha- the Colomi farmers used their own seeds or seeds produced bamba (five). They bought oca tubers for consumption in in the region. In contrast to the farmers, generally most of large or small quantities from all the farmers wishing to the merchants simply named landraces by their principal sell. The final destinations of merchandise were the big color, leading to confusion between various landraces of a similar color.

At sowing time

The merchants interviewed at sowing time were all selling seeds (only of cash landraces) and not buying. They dis- played their merchandise in two different places, according to its origin. The four merchants from Colomi whom we interviewed were installed in the covered market. They all exclusively sold seeds bought from Colomi farmers, who were also their clients except for one who also sold to a retailer from La Paz. The six other merchants interviewed, installed in a square apart from the covered market, were all from the nearby communities of Kotani (ﬁve of them) and Aguire (one of them), which usually do not depend on the Colomi market. These communities are situated at a higher altitude than most of the Colomi communities. All the merchants of Kotani and Aguire interviewed were also farmers. They specialized in seed production and afﬁrmed that their seeds carried fewer diseases than those produced in Colomi. They usually sold to Colomi farmers.

Discussion

Landrace diversity

Fig. 3 Proportions and frequencies of the different uses of k’ipas (in Eleven different landraces were listed in the four commu- percentage of farmers) nities studied. This number has to be considered in context, 123 Effect of the management of seed ﬂows and mode of propagation on the genetic diversity in an…

Fig. 4 Origin and destination of the seeds sold in Colomi market. The information was obtained from the 20 interviews held in the market. Final destination cities were cited as examples by the merchants; the list is therefore not complete

as different farmers could attribute the same names to other crops such as potato and rice in traditional manage- different landraces or give different names to the same ment systems (Zimmerer 1996; Rana et al. 2007). How- landraces. Such discrepancies in the use of names have ever, in those studies, the number of cultivated landraces been observed by Bianco and Sachs (1997) and Bradbury was correlated to the total owned land; therefore the and Emshwiller (2011) for oca and Quiros et al. (1990) for authors explained that wealthier farmers possessed more potato and is due to the use of very few characteristics to available land to cultivate more landraces. In contrast, in differentiate landraces (principally the colors and secon- the present study, no direct statistically valid correlation darily the texture and flavor of tubers). Moreover, it is between land possession by the farmers and the number of possible that farmers omitted landraces cultivated in small cultivated landraces was found. However, the number of quantities or intended to a particular use, because they do landraces was correlated to the quantity of oca the farmers not consider those as important (Almekinders and Lou- sowed and harvested. Thus it seems that wealthier farmers waars 1999). make the choice to cultivate a higher surface proportion with oca and grow more landraces of oca, independently of the land area they own. According to Mayer and Glave Cash and self-consumption landraces (1999), wealthier farmers are better endowed with agricultural resources and skills. Their practice of cultivating A few cash landraces are cultivated by almost all farmers more landrace diversity could be due to a wish to diversify (95 % of farmers cultivated at least one cash landrace). The in order to ensure a higher yearly income by counteracting market stimulates the cultivation of those more homoge- the variability of yields and prices of individual landraces, nous and productive landraces. In contrast, the diversity of as postulated by various authors (Bellon 1996; Bianco and self-consumption landraces represents more than half of Sachs 1997; Alvarez et al. 2005; Vigouroux et al. 2011). the total observed diversity (6 out of 11 landraces grown by Moreover, wealthier farmers have a better access to labor, farmers) but is owned by a small percentage of the inter- being able to pay daily workers. Zimmerer (1991) showed viewed farmers (only 36 % of them grew at least one). that the better availability of labor would enable farmers to Farmers keep using these landraces because they have undertake the greater complexity of tasks coming with other uses and tastes than the cash landraces, because they cultivating more landraces. In this study, we only gathered are more adapted to the local ecosystems or because they a logical value fro each farmer (yes or no) on daily workers are part of their cultural heritage, as observed in other employment. We found no statistically valid relation studies on tuber crops in the Andes (Terrazas and Valdivia between these values and landrace diversity. In order to 1998; Ramirez 2002; Vela´squez-Milla et al. 2010). Elderly confirm this hypothesis, gathering more precise informa- farmers explained that young farmers are not interested in tion (e.g. the number of workers or the quantity of work those landraces anymore. This conjunction of limited rep- realized by the workers) is necessary. resentation and of loss of interest of the younger genera- tions makes self-consumption landraces vulnerable to The use of k’ipas genetic erosion. Two-thirds of the farmers use k’ipas for other than pig Wealth as a driving force for diversity conservation feeding. Although some farmers seem to sell k’ipas systematically, most of them sell those tubers only following Wealthier farmers cultivate more landraces than poorer unexpected events such as a sudden need for cash, to farmers. This confirms the results of Bianco and Sachs complete a bag or after a bad harvest. Similarly, half of the (1997) from a community in Peru. This is also observed for farmers use k’ipas as seeds but only when they lack regular

123 M. Bonnave et al. seeds. Therefore, farmers seem to consider k’ipas as a Baniya et al. (2001) identified similar observations for the safety net against unforeseen events. finger millet crop in Nepal, where acquiring seeds from Farmers are not aware that k’ipas can originate from other farmers is considered as a mark of incompetence for botanical seeds. Farmers do not seem to willingly select the farmers. and propagate plants arising from sexual reproduction as it Farmers usually buy seeds of landraces they already has been observed for potato in Peru (Quiros et al. 1992) cultivated and very few sometimes tried out new landraces. and cassava in Guyana (Elias and Mckey 2000; Elias et al. As the market usually does not provide information on the 2001). However, their observations of different morpho- field performances of the seeds, farmers could be unwilling types in the fields previously cultivated with oca, especially to take the risk of trying out new landraces (Lipper et al. after a few years, indicate that they probably observed such 2009). Even when the farmers buy seeds of a landrace they plants without knowing their origin. The farmers only use know, they still evaluate their performance by sowing the k’ipas as seeds when their colors matched those of known new seeds apart from those they produced the previous landraces, and incorporate them into those landraces year. In the light of these results, it seems that a seed without later distinction. As the sole use of color does not certification process, which would provide the information permit one to distinguish different genotypes from each on performance of unknown landraces that is currently other, it is more than probable that new genotypes are lacking, could enhance the adoption of such landraces. incorporated into the landraces as it was suggested for potato by Johns and Keen (1986) and Brush et al. (1981). Wealth as a driving force for diversity propagation This concurs with our previous results (Bonnave et al. 2014): plantlets originating from botanical seeds were A higher proportion of wealthier farmers sell and buy observed in various communities (two of them in Cande- seeds, and more frequently, than do poorer farmers. Seed laria) and molecular studies proved that incorporation of sales and purchases, which are mostly monetary transac- new genotypes issuing from sexual reproduction into the tions, are easier to realize for wealthier farmers. Moreover, cultivated landraces is highly probable. most of the farmers who do not renew their seed stock consider that this practice do not enhance yield, the Seed exchanges opposite opinion to those farmers who renew it. Wealthier farmers might have a higher degree of agronomical An important proportion of the farmers (73 %) renew their knowledge than the poorer farmers, resulting in a better seed stock of oca. Almost all of them renew their seeds at understanding of the degeneration of seeds over the years, the market, where only the cash landraces are available. and in an adapted reaction to yield decreases. Finally, as Only 18 % of the farmers acquire seeds directly from their wealthier farmers have a higher production than the poorer neighbors or from farmers in other communities. This low farmers, it might be easier for them to conserve tubers from proportion of direct exchanges could reflect a weakening of the harvesting to the sowing period and to sell them as the social structure of the communities studied, as farmers seeds, and avoid selling or consuming them during the dry often explain that market exchanges are more trustworthy. season. As suggested by Subedi et al. (2003), those farmers Although farmers do not explain the reason of their higher can therefore be considered as nodal farmers, implicated in trust in market exchanges over direct exchanges, it could many exchanges, and could act as the principal guardians be due to the presence of a formal potato seed supply (for of diversity in the region. which quality is ensured) at the market, therefore increasing farmers’ trust in market seed exchanges. However, Cash and self-consumption landraces buying seeds from the market may be seen as modern by farmers, therefore influencing them to declare to the The market only provided cash landraces. Self-consump- interviewers that they buy most of their seeds at the market. tion landraces can only be exchanged directly, and cash An important imbalance was observed between farmers landraces are sometimes exchanged in this way. As it is not who declared that they sold seeds to neighbors and those a regular practice, it seems that self-consumption landraces that declared they bought seeds from neighbors. The social are not regularly exchanged, in contrast to cash landraces, prestige of selling seeds may be one of the reasons for which benefit from the dynamism of market exchanges. farmers being more willing to declare having sold seeds The high rates of exchanges of cash landraces favor a than having bought some. In contrast, buying seeds at a continual mix of their gene pools. Self-consumption lan- place other than the market could show low social prestige draces, which are less exchanged, are exposed to consid- that could drive farmers to avoid declaring such purchases. erably more genetic drift.

123 Effect of the management of seed ﬂows and mode of propagation on the genetic diversity in an…

The market as an international exporter and local importer them, the incorporations are not spread; and as self-con- of landraces sumption landraces are more exposed to genetic drift, the new genotypes can quickly be lost. Seeds produced in the Colomi region are exported almost Such incorporations into cash landraces should be less everywhere oca grows in Bolivia and probably even to frequent because of the stricter morphological criteria other countries such as Peru and Argentina. As observed defined by the market. However, because of the dynamism for potato by Almekinders et al. (2009) in the markets of of the exchanges for those landraces, just one incorporation the Cochabamba region, wholesalers and retailers play an can model the genetic diversity in several regions of the important role in the transfer of the genetic diversity of the country. This concurs with our previous molecular study of oca cultivated by the Colomi farmers, by selecting, trans- the genetic diversity of landraces (Bonnave et al. 2014)in porting and selling seeds to distant regions. Lipper et al. the same region, which showed that the K’ellu Kayara cash (2009) noted that, in various marketplaces of the world, landrace, the landrace most cultivated by the farmers of the merchants seemed to treat identification of landraces more interviewed communities, is composed of genotypes that casually than did farmers, simply naming them by their arose from at least five different sexual reproduction color. This leads to confusion between different landraces events. Seed exchanges may, therefore, have regrouped and could result in highly genetically heterogeneous lan- genotypes arising from sexual events that took place in draces, as observed in our previous study (Bonnave et al. different places of the country, resulting in the creation of 2014). landraces that are genetically highly heterogeneous. In contrast, the seeds sold to the Colomi farmers come from Colomi communities or nearby regions. Farmers Conservation strategies seem to pay attention to the origin of those seeds, not buying seeds from their own community. It appeared that a Results show the importance of taking into account the few communities are specialized in seed production. existence of two different landrace profiles. As Bellon and Farmers from those communities explained that they pro- Hellin (2011) observed for maize, cash and self-con- duced seeds of better quality, with fewer diseases. The sumption landraces can be considered as two different higher altitudes at which farmers from those communities germplasms with two distinct, although overlapping (cash cultivated seem to allow the production of healthier tubers, landraces are also consumed by the farmers’ families), which are favored by farmers as seeds. This seems to be functions in farmers’ livelihoods. They have different consistent with the fact that the farmers interviewed patterns of diversity, management and seed exchanges. observed an altitudinal rotation in their own fields, as also Therefore, these two profiles need to be addressed differ- observed by Thiele (1998) for potato. High altitude would ently when planning conservation strategies. permit a considerable reduction in seed degeneration by Cash landraces are not numerous but are well repre- slowing down or stopping the cycles of pests and diseases, sented in the communities, are cultivated in large quanti- leading to the production of healthier seeds than those ties, and are present an important intra-landrace diversity obtained at lower altitude. Altitude could also permit a because of the numerous seed exchanges organized by the better conservation of seeds in the dry season. Finally, the farmers with the support of the market. The market seems very low frequency of catastrophic climatic events and the to guarantee the conservation of those landraces. In con- production in repeated fields under different climatic contrast, self-consumption landraces are owned in small ditions almost always ensure sufficient seed production, quantities by very few farmers and are not exchanged reducing the need for buying seeds. often. However, they represent more than half of the observed landrace diversity in the studied communities. Spread of new genotypes arising from sexual reproduction This part of the landrace diversity is therefore very sensi- tive to genetic erosion and to a bottleneck effect leading to As self-consumption landraces most often differ from one the permanent loss of unique landraces and of the genes farmer to another and seeds of those landraces cannot be they carry. It seems that lack of a market demand for these bought at the market, it is more difficult for farmers to find landraces is the most important incentive to abandon their such seeds in case of need. Farmers will therefore probably cultivation. obtain some in fields of k’ipas. Moreover, the selection Therefore, the incorporation of a landrace into the criteria of seeds are not as strict as those for cash landraces. market system seems to augment the chances of long-term Incorporations of new genotypes into self-consumption conservation of this landrace, as postulated by Lipper et al. landraces are therefore more likely than into cash lan- (2009). Measures promoting a more varied demand by draces. However, as those landraces are not much consumers could permit the conversion of self-consumed exchanged between farmers and are not owned by many of landraces into cash landraces and an increase in genetic 123 M. Bonnave et al. diversity that benefits from the important support of the and very vulnerable to genetic erosion. The lack of exchan- market for conservation and propagation. ges of these landraces creates a bottleneck in which genetic On the other hand, the maintenance of local self-con- diversity is invariably lost. This progressive loss is alarming sumed landraces is important because it allows the con- since the evolutionary potential to adapt to changing envi- servation of potentially interesting genes independently ronmental conditions mainly resides in the diversity of these from market pressure. In contrast to cash landraces, these locally adapted landraces. Therefore, conservation strategies landraces, which are conserved independently, are less must focus on the preservation of these endangered genetic subject to homogenization of their genetic resources, as resources. Local and international genetic diversity conser- they are not usually exchanged. The sociocultural traditions vation programs must consider the positive and negative (e.g. culinary, language, religion) that drive the farmers to effects of the markets while developing their strategies, as conserve these landraces are very fragile components of the these have a growing influence on the genetic diversity of agrarian system (Vigouroux et al. 2011). The conservation crops. Complementary conservation strategies should be of these traditions seems to be a good way to preserve the implemented, promoting landrace diversity at the market genetic diversity of these landraces. Both resistance to level and supporting the sociocultural traditions that drive cultural discrimination, and educational programs to the local conservation of landraces. encourage young farmers’ perpetuation of traditions, need to be encouraged (Vela´squez-Milla et al. 2010). However, Acknowledgments The authors would like to thank all the farmers the perpetuation of traditions cannot be sustainable if it and merchants who contributed to this study. MB, TB and PB would like to thank Antonio Gandarillas and all the staff of the PROINPA prevents farmers from attaining their wish for modernity foundation, especially Franz Terrazas, Ximena Cadima, Rhimer and a secure future for their children, to which the driving Gonza´les and Julio Gabriel. MB acknowledges the support of fel- market force can contribute. Complementary, innovations lowships from Fonds pour la formation a` la Recherche dans l’In- solutions are needed to encourage farmers to conserve dustrie et dans l’Agriculture (Fund for Research Training in Industry and Agriculture, Belgium). PB thanks the Conseil de la Recherche of diversity while being integrated in today’s world. Zim- UCL. merer (2002) proposed initiatives such as communitarian seed banks, diversity fairs (already in place in Candelaria, although more directed towards potato conservation) or References associations of ‘conservation farmers’ as good ways to promote self-consumed landrace conservation. Finally, the Almekinders, C.J., and N.P. Louwaars. 1999. Farmers’ seed produc- creation of a yearly market (at sowing time) dedicated to tion: New approaches and practices. London: Intermediate seed exchanges would permit farmers to exchange seeds of Technology Publication Ltd. Almekinders, C.J., R. Cavatassi, F. Terceros, P.R. Romero, L. landraces that cannot be found in the traditional market. Salazar, L. Lipper, and T.J. Dalton. 2009. Potato seed supply and Promoting seed exchanges of those landraces would also diversity: Dynamics of local markets of Cochabamba Province, permit the propagation of new genotypes obtained by Bolivia—a case study. In Seed trade in rural markets: Implica- sexual reproduction. tions for crop diversity and agricultural development, ed. L. Lipper, C.L. Anderson, and T.J. Dalton, 75–94. London: FAO and Earthscan. Alvarez, N., E. Garine, C. Khasah, E. Dounias, M. Hossaert-McKey, Conclusions and D. McKey. 2005. Farmers’ practices, metapopulation dynamics, and conservation of agricultural biodiversity on-farm: A case study of sorghum among the Duupa in sub-sahelian Although seed exchanges have been thoroughly studied in Cameroon. Biological Conservation 12: 533–543. the Andes region for the potato crop, they have been poorly Baniya, B.K., A. Subedi, R.B. Rana, R.K. Tiwari, and B. Chaudhary. studied for the other tuber and minor crops of this region. 2001. Finger millet seed supply system in Kaski district of Even if no formal seed system exists for most of these crops Nepal. In On farm management of agricultural biodiversity in Nepal. Proceedings of a national workshop, 24–26. Kathmandu: in this region (apart from potato), the increase of the use of NARC/LI—BIRD/IPGRI. the market in seed exchanges has an important effect on their Bellon, M.R. 1996. The dynamics of crop infraspecific diversity: A genetic diversity. The market favors the cultivation and conceptual framework at the farmer level. Economic Botany 50: exchange of a few cash landraces, which present a highly 26–39. Bellon, M.R., and J. Hellin. 2011. Planting hybrids, keeping heterogeneous genetic diversity that is constantly mixed up. landraces: Agricultural modernization and tradition among Cash landrace seeds can be transported long distances. small-scale maize farmers in Chiapas, Mexico. World Develop- Moreover, in the case of tuber crops, sexually produced new ment 39: 1434–1443. genotypes incorporated in cash landraces are more likely to Bernard, H.R. (ed.). 2006. Research methods in anthropology: Quali- tative and quantitative approaches, 4/e. Oxford: AltaMira Press. be spread, as observed for oca. On the other hand, self-con- Bianco, M., and C. Sachs. 1997. Growing Oca, Ulluco, and Mashua in sumed landraces, which still represent an important pro- the Andes: Socioeconomic differences in cropping practices. portion of the existing genetic diversity, seem to be isolated Agriculture and Human Values 15: 267–280. 123 Effect of the management of seed flows and mode of propagation on the genetic diversity in an…

Bonnave, M., G. Bleeckx, J. Rojas Beltrań, P. Maughan, M.-C. of the vegetatively propagated Andean tuber crop, Mashua Flamand, F. Terrazas, and P. Bertin. 2014. Farmers’ unconscious (Tropaeolum tuberosum), highlighted by Intersimple Sequence incorporation of sexually-produced genotypes into the germ- Repeat Markers and Multivariate Analysis Methods. Interna- plasm of a vegetatively propagated crop (Oxalis tuberosa Mol.). tional journal of plant science 169: 1248–1260. Genetic Resources and Crop Evolution 61: 721–740. Pissard, A., J. Rojas Beltrań, and A.-M. Faux. 2008b. Evidence of Bradbury, E.J., and E. Emshwiller. 2011. The role of organic acids in intra-varietal genetic variability in the vegetatively propagated the domestication of Oxalis tuberosa: A new model for studying crop oca (Oxalis tuberosa Mol.) in the Andean traditional domestication resulting in opposing crop phenotypes. Economic farming system. Plant Systematics and Evolution 270: 59–74. Botany 65: 76–84. PRODISEC. 2002. Plan de desarollo municipal ajustado 2003–2007 Brush, S.B., H.J. Carney, and Z. Huamań. 1981. Dynamics of Andean del gobierno municipal de Colomi. Colomi: Viceministerio de potato agriculture. Economic Botany 35: 70–88. planificacion estrategica y participacion popular. de Haan, S. 2009. Potato diversity at height: Multiple dimensions of Quiros, C.F., S.B. Brush, D.S. Douches, K.S. Zimmerer, and G. farmer-driven in situ conservation in the Andes. PhD thesis Huestis. 1990. Biochemical and folk assessment of variability of Wageningen University, The Netherlands. Andean cultivated potatoes. 1990. Economic Botany 44: Elias, M., and D. McKey. 2000. The unmanaged reproductive ecology 254–266. of domesticated plants in traditional agroecosystems: An exam- Quiros, C.F., R. Ortega, L. Raamsdonk, M. Herrera-Montoya, P. ple involving cassava and a call for data. Acta Oenologica 21: Cisneros, E. Schmidt, and S.B. Brush. 1992. Increase of potato 223–230. genetic resources in their center of diversity: the role of natural Elias, M., D. McKey, O. Panaud, M.C. Anstett, and T. Robert. 2001. outcrossing and selection by the Andean farmer. Genetic Traditional management of cassava morphological and genetic Resources and Crop Evolution 39: 107–113. diversity by the Makushi Amerindians (Guyana, South Amer- R Core Team. 2013. R: A language and environment for statistical ica): Perspectives for on-farm conservation of crop genetic computing. Vienna: R Foundation for Statistical Computing. resources. Euphytica 120: 143–157. Ramirez, M. 2002. On farm conservation of minor tubers in Peru: The Emshwiller, E. 2006. Evolution and conservation of clonally prop- dynamics of oca (Oxalis tuberosa) landrace management in a agated crops. Insights from AFLP data and folk taxonomy of the peasant community. Plant Genetic Resources Newsletter 132: Andean tuber oca (Oxalis tuberosa). In Darwin’s harvest, ed. 1–9. T.J. Motley, N. Zerega, and H. Cross, 308–332. New York: Rana, R.B., C. Garforth, B. Sthapit, and D.I. Jarvis. 2007. Influence of Columbia University Press. socio-economic and cultural factors in rice varietal diversity Espinoza, J. 1998. Comercializacioń y consumo de tube´rculos management on-farm in Nepal. Agriculture and Human Values andinos en la regioń de Cochabamba. Sub-proyecto R5-002. 24: 461–472. Programa colaborativo biodiversidad de raıćes y tube´rculos Subedi, A., B. Chaudhary, B. Baniya, R.B. Rana, R.K. Tiwari, D. andinos. Cochabamba: CIP-CODUSE-CONDESAN. Rijal, and D.I. Jarvis. 2003. Who maintains genetic diversity and Ezeta, F.N. 2001. Produccioń de semilla de papa en latinoame´rica. how? Policy implications for agro-biodiversity management. In Revista Latinoamericana de la Papa 12: 1–14. Agrobiodiversity conservation on-farm: Nepal’s contribution to Garcıá, W., and X. Cadima. 2003. Manejo sostenible de la a scientific basis for national policy recommendations, 10 agrobiodiversidad de tube´rculos andinos: Sıńtesis de investiga- February 2002, Kathmandu, Nepal, ed. D. Gauchan, B.R. ciones y experiencias en Bolivia. Cochabamba: Fundacioń Staphit, and D.I. Jarvis. Rome: IPGRI. PROINPA. Tamiru Oli, M. 2006. Assessing diversity in yams (Dioscorea spp) Huamań, Z. 2001. Semilleros comunales de papas nativas del Peru´. from Ethiopia based on morphology, AFLP markers and tuber Biodiversidad 30: 20–22. quality, and farmers’ management of landraces.Go¨ttingen: Johns, T., and S.L. Keen. 1986. Ongoing evolution of the potato on Cuvillier Verlag. the altiplano of western Bolivia. Economic Botany 40: 409–424. Tapia, C., and J. Estrella. 2001. Genetic erosion quantification in Lipper, L., T.J. Dalton, C.L. Anderson, and A. Keleman. 2009. Ullucus (Ullucus tuberosus Caldas), oca (Oxalis tuberosa Mol.) Agricultural markets and the sustainable utilization of crop and mashua (Tropaeolum tuberosum R.&P.). In Proceedings of genetic resources. In Seed trade in rural markets: implications for the international symposium ‘Managing biodiversity in agricul- crop diversity and agricultural development, ed. L. Lipper, C.L. tural ecosystems,’ 8–10 November 2001. Montreal. Anderson, and T.J. Dalton, 75–94. London: FAO and Earthscan. Terrazas, F., and G. Valdivia. 1998. Spatial dynamics of in situ Malice, M., C.L. Villarroel Vogt, A. Pissard, C. Arbizu, and J.-P. conservation: handling the genetic diversity of Andean tubers in Baudoin. 2009. Genetic diversity of the Andean tuber crop mosaic systems. Plant Genetic Resource Newsletter 114: 9–15. species Ullucus tuberosus as revealed by molecular (ISSR) and Thiele, G. 1998. Informal potato seed systems in the Andes: Why are morphological markers. Belgian Journal of Botany 142: 68–82. they important and what should we do with them? World Mayer, E., and M. Glave. 1999. Alguito para ganar (a little something Development 27: 83–99. to earn): Profits and losses in peasant economies. American Trognitz, B., M. Hermann, and S. Carrioń. 1998. Germplasm Ethnologist 26: 344–369. conservation of oca (Oxalis tuberosa Mol.) through botanical McKey, D., M. Elias, B. Pujol, and A. Duputie´. 2010. The seed. Seed formation under a system of polymorphic incompat- evolutionaly ecology of clonally propagated plants. New Phy- ibility. Euphytica 101: 133–144. tologist 186: 318–332. UNDP. 2013. Human Development Report 2013. New York: United Pautasso M., A. Guntra, A. Barnaud, S. Caillon, P. Clouvel, O.T. Nations Publications. Coomes, M. Deleˆtre, E. Demeulenaere, et al. 2012. Seed Vela´squez-Milla, D., A. Casas, J. Torres-Guevara, and A. Cruz- exchange networks for agrobiodiversity conservation. Agronomy Soriano. 2010. Ecological and socio-cultural factors influencing for sustainable development 33: 151–175. in situ conservation of crop diversity by traditional Andean Pissard, A., M. Ghislain, and P. Bertin. 2006. Genetic diversity of the households in Peru. Journal of Ethnobiology and Ethnomedicine Andean tuber-bearing species, oca (Oxalis tuberosa Mol.), 7: 40. investigated by inter-simple sequence repeats. Genome 49: 8–16. Vigouroux, Y., A. Barnaud, N. Scarcelli, and A.-C. Thuillet. 2011. Pissard, A., C. Arbizu, M. Ghislain, and P. Bertin. 2008a. Influence of Biodiversity, evolution and adaptation of cultivated crops. geographical provenance on the genetic structure and diversity Comptes Rendus Biologies 334: 450–457.

123 M. Bonnave et al.

Zeven, A.C. 1999. The traditional inexplicable replacement of seed Thomas Bleeckx received his master degree from the faculty of and seed ware of landraces and cultivars: A review. Euphytica bioscience engineering of the Universite´ catholique de Louvain. 110: 181–191. Zimmerer, K.S. 1991. Labor shortage and crop diversity in the Franz Terrazas received his master degree from the Gembloux agro- southern Peruvian sierra. Geographical Review 81: 414–432. bio Tech faculty of the Universite´ de Lie`ge. He works as a genetic Zimmerer, K.S. 1996. Changing fortunes: Biodiversity and peasant resources researcher at the PROINPA. His research is centered on the livelihood in the Peruvian Andes. Berkeley, CA: University of in situ conservation of Andean crops. California Press. Zimmerer, K.S. 2002. Geographies of seed networks for food plants Pierre Bertin is the group leader of the research on genetic (potato, ulluco) and approaches to agrobiodiversity conservation variability of crop species in the laboratory of Ecophysiology and in the Andean countries. Society & Natural Resources 16: Plant Breeding of the Earth and Life Institute at the Universite´ 583–601. catholique de Louvain (UCL). His research is centered on the genetic diversity of crop species and on the use of this genetic diversity for breeding purposes. Maxime Bonnave received his doctorate in 2015 from the Earth and Life Institute, Universite´ catholique de Louvain, in Belgium. His work has been centered on the study of the genetic diversity of Andean underused and neglected tuber crops.

123