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Genetic resources and breeding of the Andean grain crop quinoa (Chenopodium quinoa Willd.)Sven-Erik Jacobsen Angel Mujica Introduction
Quinoa (Chenopodium quinoa Willd.) originated in the Andean region near Lake Titicaca in Peru and Bolivia, where the greatest genetic diversity is found (Gandarillas 1974). Cultivation of this very old crop spread northward to Colombia and southward to Chile (Bukusov 1965).
The species closest to cultivated quinoa are C. hircinum and C. berlandieri, whose number of basic chromosomes (2n=4x=36) is the same as that of the cultivated types, and C. petiolare and C. pallidicaule, which have 2n=2x=18 chromosomes. In each centre of diversity, morphological and electrophoretic similarities have been observed between the populations of cultivated quinoa and the wild species. This indicates that cultivated quinoa is usually accompanied by related wild populations (Jacobsen et al. 2000).
Several areas are considered centres of quinoa diversity, including the borders of Lake Titicaca, the salt deserts of Bolivia, the Mantaro valley and Callejón de Huaylas in Peru, the highlands of Ecuador, the southern part of Colombia, southern Chile, and north-eastern Argentina. Although institutions in several countries maintain Chenopodium genebanks, cultivated material and wild types from many areas remain uncollected (Table 1).
Quinoa breeding programmes have been conducted in several countries to improve yield, resistance to adverse factors, adaptation to different agro-climatic conditions (such as modern agriculture), and suitability for transformation into manufactured food products. Breeding techniques have included mass selection, individual selection and crossings.
Conservation and use of quinoa genetic resources when generating new varieties is essential for the sustainability of future production. Breeding programmes have succeeded in developing a small number of new varieties that outyield landrace varieties. Although these new varieties have improved production, their small number and consequent lack of genetic diversity endanger the future of quinoa production. Farmers have willingly adopted improved varieties throughout the altiplano, and a few varieties representing a very narrow genetic base are replacing landraces, a process known as genetic erosion. Thus, efforts to increase the number and genetic diversity of new varieties while simultaneously conserving landraces are essential (Bonifacio et al. 2001a).
Important centres of diversity
In growth habits and other characteristics, the greatest diversity in cultivated and wild-type quinoa is found in specific areas of the Andean region, as indicated in Table 2.
History of crop distribution
Quinoa distribution started with the expansion of the Inca empire, which extended from Pasto in Colombia down to the river Maule in Chile and to Catamarca in Argentina. In Colombia, quinoa (suba) was cultivated, utilized, and disseminated by the Chibchas, who extended its cultivation to the savannah of Bogota (Pulgar Vidal, 1954). In Ecuador, it has mainly been cultivated in the central mountain region. In Peru, the crop has been cultivated in different agro-climatic areas: the inter-Andean valleys and the altiplano, and recently in the arid mountain zone and coastal region. A core collection has been developed, consisting of 103 accessions, representing the diversity existing in the country (Ortiz et al. 1998a,b; 1999). In Bolivia, quinoa is distributed in the altiplano, the inter-Andean valleys, and the salt deserts of the south, with special characteristics of cultivation, processing and use in each region. Rojas et al. (2000) have shown that in the Bolivian altiplano there are four areas of diversity, one more than previously considered. In Chile, the crop is located in the border areas of the Bolivian altiplano, and in the south at sea level in Concepción and Valdivia, traditionally cultivated by the Araucans who distributed it to the Island of Chiloe (southern latitude 47º). In Argentina quinoa was cultivated down to Catamarca, but, because of competition from other crops, it has receded to the north-eastern part in the area of San Juan de Jujuy.
Quinoa has been introduced to other South and Central American countries for research and production through international development programmes, such as PROCISUR, PROCIANDINO and JUNAC, and the Food and Agriculture Organization (FAO). Quinoa has been introduced to the United States (Johnson 1993), where it is produced commercially, and to Europe (Risi and Galwey 1989; Limburg and Mastebroek 1996; Jacobsen 1997, 1999; Jacobsen and Risi 2001). A close relative to quinoa, the huanzontle (Chenopodium berlandieri ssp. nuttaliae) is grown in Mexico, and a grain chenopod, probably Chenopodium album, is grown in Tibet (Partap et al. 1998).
The genetic material of the Andean region is exchanged and disseminated at the individual level between investigators, research institutes, and international institutions and programmes. The interest in quinoa and the demand for the crop as a commodity is increasing, both nationally in the Andean countries and internationally from the USA and Europe (Nieto et al. 2000; Mujica et al. 2001). This is due to its modest demands for fertilizers and pesticides, an extreme tolerance to drought and saline soils (Mujica and Jacobsen 2001), and a high nutritive value due to a high protein quality and a high content of a range of minerals and vitamins (Jacobsen et al. 2001). For export the main demand is for organically produced quinoa (Nieto et al. 2000). The characteristics mentioned, along with its adaptability to different agroclimatic conditions, make it a potential crop for a wide range of agroclimatic conditions in South America and elsewhere (Jacobsen and Risi 2001), and several new products may be developed from quinoa (Jacobsen and Mujica 2000).
Importance of wild-type quinoa as a source of diversity
Wild-type quinoa, called ayaras or aspha quinoa, is distinguished from cultivated quinoa by its small, black seeds and its persistence outside the cultivated field. It is widely disseminated in quinoa cultivation areas of the Andes and in potential areas of expansion. These wild quinoas are more similar to the cultivated quinoa grown in the same area, than to other Chenopodium species, so that their inclusion into the species C. quinoa has been suggested (Wilson 1990). The wild species are important not only because of their high level of resistance to adverse factors, but also because they may contain useful chemical substances such as saponins, essential oils, vitamins and amino acids in higher amounts or better quality than in cultivated quinoa. At some point in the quinoa breeding, it will be desirable to use genes that govern production of these active ingredients and provide sources of resistance. These genes could also be used to develop other characteristics such as rapid root development, increased protein content, increased stomata sensitivity, higher level of calcium oxalate in leaves, and more pigmentation, all important characteristics for improving the species.
The genus Chenopodium contains more than 120 species, divided into 16 sections (Aellen 1960), including herbaceous species (Agathophyton), suffrutescents (Ambrine), and arboreal perennials (Skottsbergia), with the majority being annuals. The cultivated grain species are found in the section Chenopodium, which includes four sub-sections: Cellulata, Liosperma, Undata, and Grossefoveata. The sub-section Cellulata (2n=4x=36) is characterized by an alveolary pericarp, e.g. C. quinoa Willd. and C. berlandieri ssp. nutalliae. Its closest cultivated and wild types are C. hircinum (also known as C. quinoa ssp. milleanum) and C. quinoa ssp. melanospermum, respectively. The sub-section Liosperma (2n=2x=18), characterized by smooth grains, includes cañihua (C. pallidicaule Aellen).
The tetraploid species distributed throughout America, possibly derived from diploid types, originated in western North America and subsequently dispersed to the current locations in Central and South America (Wilson 1990). According to Wilson (1976) there are three branches of wild-types in the sub-section Cellulata developed through adaptive radiation, including evolution under direct human selection, in three areas: (a) South American, with C. hircinum and C. philippianum as the main species, (b) Northeast American, with C. bushianum and C. macrocalycium, and (c) Northwest American, with C. berlandieri.
All relatives (progenitors) of quinoa in South America are in the section Cellulata, which are also the wild types most important for improving and diversifying quinoa (Wilson 1980) (Table 3).
These wild types should be collected, characterized, and conserved for future use in improving quinoa. An example of the effective use of interspecific crossing is that produced with the C. hircinum (tetraploid) and C. petiolare (diploid) species, from which was obtained an allotetraploid (2n=4x=36) with all the characteristics of C. quinoa (Gandarillas 1984).
Gaps in current genebanks in genetic diversity and geographical representation
There are many gaps in current genebank collections, both within and outside the Andes (Table 1). In some cases this is due to a lack of collection, and in other cases due to losses experienced during conservation or replenishment of the germplasm. Brenner and Widrlechner (1998) described a seed generation method for amaranth (Amaranthus sp.) in plastic tents within greenhouse, which was very effective with only 0.01% pollen contamination between tents.
In terms of genetic diversity, the following quinoa types still need to be collected: quinoa chullpi; ayara; pasankallas (early-maturing quinoa with large seed size); cultivated and wild-type quinoa with tolerance to salinity, frost, acidity, excess moisture, and heat; valley quinoa producing green forage and leafy vegetables; quinoa with resistance to downy mildew (Peronospora farinosa) (Danielsen et al. 2001), hail, and Eurysacca quinoae (q´hona q’hona) (Rasmussen et al. 2001); and wild Chenopodium sp.
For complete geographical representation, collections are needed in the islands of Lake Titicaca (Amantani, Taquile, Capachica peninsula, Chucuito peninsula, Luquina); the mountain areas of Puno (Azángaro, Cruiser, Macusani, Ayaviri, Santa Rosa); the mountain areas of Ilave (Nuñoa, Lampa, Pucará); the highland jungle (Ollachea, Phara, Patambuco); the mountain areas of Arequipa (Colca valley, Chuquibamba, Cotahuasi); the mountain areas of Cusco (Espenar, Canas, Ocongate, Chumbivilcas, Paucartambo); and the highland jungle of Cusco (Amparaes, Lares, Valley of the Mapocho-Quispicanchis River). In Ayacucho, potential collection sites include the dry areas of Vinchos and Pampa Cangallo; in central Peru, all cultivated areas of Huancavelica (mainly wild types); in Huancayo, the wild types of mountain areas; in Huaraz, Chiquian; in Cajamarca, the vicinity of Michiquillay (quinoa that grows in acid soil); in Lima, Province of Yauyos; in Piura, the Valley of Huancabamba; and all of the eastern slope of the Peruvian Andes, from Cajamarca to Puno.
In Bolivia, the cultivars pandelas, chullpis and pasankallas should be collected for future use for characteristics such as low saponin content and large grain size, and for resistance to salinity, frost, drought, and downy mildew. To preserve geographic distribution, wild types should be collected from the islands and around Lake Titicaca, areas above 3900 m, the salt deserts of Coipasa and Uyuni, Lake Poopó, the eastern slope of the Bolivian Andes (La Paz to Tarija), and the valleys of Cochabamba, Chuquisaca and Potosí.
In Ecuador, cultivars with characteristics such as short growing periods, resistance to mildew, and large green-matter production should be preserved. To maintain geographic distribution, collection should cover the high zones of Carchi, Imbabura, Pichincha, Cotopaxi, Tungurahua, Chimborazo (mainly wild types); the high areas of Cañar; and the eastern mountain range of the Ecuadorian Andes.
In Colombia, geographic distribution of quinoa and diversity should be preserved by collecting forage-producing species with large seeds, resistance to mildew, and low saponin content in Nariño, Pasto, Boyaca, Cundinamarca, and Ipiales (mainly wild type quinoa).
Chilean cultivar collections should include those that are less sensitive to day-length, early-maturing, and without saponin. To maintain the characteristics of these species, and their geographic distribution, quinoa should be collected in Antofagasta, Concepción, and the island of Chiloe.
Argentinian cultivars (mainly wild types) that need collection are found in high and cold areas of Salta, Jujuy, Calchaqui valley, Catamarca, and Patagonia. These species are early-maturing and have resistance to cold and drought.
Wild types from Lake Texcoco, Lake Puroepecha, Tlaxcala, Puebla, Hidalgo, Pascuaro, Oaxaca, Mistecas de Puebla, Oaxaca and Toluca, and huanzontle (Chenopodium berlandieri ssp. nuttaliae) should be collected in Mexico.
Wild diversity in C. berlanderi including high and low elevation types, and large seeded types reported from the north-east seaboard and from the south shore of the great lakes.
Quinoa breeding programmes began in 1965 in Bolivia, financed by OXFAM (Oxford Famine Relief Committee) and organized by FAO through an agreement with the Bolivian government. A few years later breeding was initiated in Peru, through the national program of Andean crops of the Instituto Nacional de Investigación Agraria (INIA). This programme seeks to improve yield and resistance to drought and frost. Similar work has been conducted in Ecuador by the Instituto Nacional de Investigaciones Agropecuarias (INIAP), and until recently by the company Latinreco on a smaller scale. This latter programme targeted improved yield and uniformity. Currently breeding is carried out in Peru at INIA, Universidad Nacional del Altiplano-Puno, and Centro de Investigaciones en Cultivos Andinos (CICA), Cusco; The foundation Promoción de Investigaciones en Productos Andinos (PROINPA), Bolivia; INIAP, Ecuador; and Universidad Arturo Prat, Iquique, Chile. Due to quinoa’s reproductive biology, the breeding methods applied in most cases are similar to those used for autogamous plants, except for cultivars that present a predominance of allogamy (e.g. ayara, ccoyto).
Breeding objectives focus on adapting quinoa to modern agriculture requirements and to commercial processing. Therefore, plant breeders seek a high yield of saponin-free, early maturing, large seeds with a high level of resistance to biotic (pests and diseases) and abiotic (drought, frosts, salinity) factors; high protein content; and uniform, short plants composed of one, terminal, compact panicle. In addition, the specific problems of rural communities in the high Andes must be addressed. Agriculture in these areas is focused on the safety of the harvest, since plants must survive extreme climatic, soil, and economic conditions. Therefore, it is desirable to orient breeding toward both food security and market. The methods used most often in the Andes are mass selection, individual selection, and hybridization (Gandarillas 1967, 1979; Risi and Galwey 1984; Jacobsen 1993; Lescano 1994; Bonifacio et al. 2001b; Trognitz 2001).
Mass selection is a method derived by Andean farmers for purifying a variety or local ecotype, in which undesired genotypes are eliminated. This method comprises the following steps:
l An outstanding cultivar is chosen from a given locality, such as Amarilla de Marangani (in Peru) or Real (in Bolivia).
l A 2000 m2 plot of mass selection is sown, isolated from other cultivars by a minimum of 50 m (or by planting time), in 50-m rows 0.80 m apart (50 m´40 m).
l Plants are spaced 10 cm apart (10 plants per m).
l Prior to selection, the field is stratified in subplots of ten 5-m rows, 8 m wide (=10 rows), for a total of 50 subplots.
l In every subplot, the best 20 plants are selected (2 per row). Plants are chosen according to the desired agronomic characteristics (plant size, earliness, yield, resistance to pests and disease, etc.). Selection is done either visually or by weighing a sample of 1000 randomly selected panicles.
l The seeds of the 1000 selected plants are mixed, and small and immature seeds are eliminated. The resulting seed is used for the first cycle of mass selection (SM1).
l The original cultivar and the seeds of the first year of mass selection (SM1) are sown to compare and measure genetic progress.
l Screened seeds obtained from SM1 are used for the second cycle (SM2). Again, the original cultivars and their seeds are sown side by side in the mass selection plot.
l This procedure is applied to several generations until genetic improvement becomes non-significant. In this way, a new, largely homozygous plant variety is obtained. However, this does not produce a completely homogeneous population due to a certain degree of outcrossing (i.e., variation will still be observed in the population of the new variety due to the broad genetic base that remains). This method is suitable for the varied climate, soil, and pest conditions that exist in the Andean region.
The following varieties have been improved via the mass selection method: Kancolla, Real, Cheweca, Blanca de Juli, Blanca de Junín, Baer, etc. (Risi and Galwey 1984). The method is simple and very practical, since the best-performing cultivar can be obtained directly from the farmer’s field and, after a few years of selection, can be used or returned to the farmer.
Individual selection allows researchers to take advantage of the great variability of the quinoa sown by Andean farmers or quinoa held in genebank collections. It entails selecting and isolating outstanding individual plants, and evaluating successive generations. In many cases, different forms, varieties, or ecotypes of quinoa are mixed together in farmers fields, which facilitates selection.
For this method to be effective, desired traits must be pre-selected by:
l Sowing a cultivar on a 2000 m2 (50 m´40 m) plot in rows 0.80 m apart, 10 plants per m (sowing may also be done directly in farmers fields).
l Plants are selected in the plot according to the desired characteristics. A total sample of 5000 plants is needed, using sample stratification to avoid selection errors caused by variation in fertility, location, or other external factors. Of these 5000 plants, 100 plants are selected.
l In the second year, plants are selfed by cultivating 4000 individual plants in 5-m rows, 0.80 m apart, with 10 cm between each plant.
l Plants with the desired characteristics of the most uniform rows are selected, and plants with undesired traits are eliminated. All or part of the row may be harvested, according to the quantity of desired material.
l In the third year, sowing 400 selected lines for evaluation of yield or other characteristics such as earliness, seed colour, plant height, and growth habit. If low saponin content is desired, start selection with selfed plants, eliminating those that are bitter-tasting (this does not require continued selfing, as the sweet flavour can be maintained via recessive genes).
l In the fourth cycle, testing the selected lines (40 in total) choosing the best ones (8–10 high-yielding, uniform plants with desirable agronomic traits).
l In the fifth year, conducting regional testing of one or two lines that outperform local cultivars in desirable characteristics.
l In the sixth year, increasing the material, launching the new variety, and distributing the improved seed obtained through the selection process.
Plants obtained through this method will be homogeneous and will have pure, homozygous characteristics. Examples include selections from Amarilla de Maranganí, Nariño, Chucapaca, Roja Coporaque, and Quillahuaman-INIA (Mujica 1993). To compare the efficiency of this selection method with conventional methodologies, Mujica (1988) estimated desirable genetic parameters for improving quinoa with highly heritable traits and constructed selection indices. Rather than selecting for yield only, other traits positively correlated to yield were used.
The optimal recommended indices are:
With one variable: I1=2.88 (diameter of the central glomerulus, with a relative efficiency of 144.48%)
With three variables: I3=2.91 (diameter of the stem)+0.23 (diameter of the panicle)+2.04 (diameter of the glomerulus with a relative efficiency of 148.32%)
The optimal index for quinoa selection should not exceed three traits, not including yield, due to the practical difficulties of analyzing multiple variables.
Hybridization seems potentially helpful in quinoa breeding for adaptation to modern production systems, seed size, disease resistance, etc. This method has potential for incorporating several desirable traits in a single variety. If large seed size, low saponin content, earliness, and short height are the desired traits, hybridization must be used, since these traits are found in different cultivars and in different environments. The problem is that hybridization using manual emasculation and pollen transfer is very difficult in quinoa, due to its large number of self-fertile, small perfect flowers, clustered together to form the inflorescence.
Other methods are being developed to differentiate crossed material from selfed material. These include the use of genetic markers, and morphological markers including plant and fruit colour, inflorescence type, and other dominant characteristics such as seed flavour. Jacobsen (1993) has evaluated a method that entails planting the selected parents together in a pot, covering them, and providing them with pollinated air inside a greenhouse. This method requires that the hybrid plants be easily recognized by morphologic or genetic markers. Careful selection of the progenitor material is crucial to ensure the success of the crossings, and it is necessary to determine the level of heritability of the main traits as well as their correlation to the parents’ traits. Mujica (1988) studied the heritability of 32 traits and identified their correlation to yield.
Ward (1998) has described a new male sterile cytoplasm in quinoa, which is stable in transmission and readily restorable. The restorer allele is widely distributed, and appears to be present at two duplicate loci in the quinoa genome. This restorable male sterile cytoplasm has great potential both for new variety development, and for the production of hybrid quinoa (Ward 1998).
Hybridization methods used include hybridization with mass selection, hybridization with genealogical selection, and hybridization with regressive crosses.
(a) Hybridization with mass selection
This method consists of crossing two selected progenitors to produce a desirable combination of characteristics. F1 seed from the crosses is sown on a sufficiently spaced and sized plot to obtain F2 seed. Seed from F2 is sown in bulk up to generation F6, from which individual plants are selected that have the desired traits of the progenitors. The selected plants are then sown in rows (one panicle per row), followed by selection between families of panicles in rows, and within the families selected. The following year, the selected lines are tested, and the outstanding lines are launched as varieties. In the F6 generation, most plants will be homozygous for most traits. A similar method was used to develop the sweet (non-bitter) variety Sajama (Gandarillas and Tapia 1976).
(b) Hybridization with pedigree selection
This method consists of crossing two progenitors with desirable characters. The F1 is planted in an area large enough to obtain sufficient F2 plants and to enable identification of the phenotypical characters. In F2, individual, outstanding plants are selected that show the phenotypical traits sought by the crossing. The selected individual plants are cultivated as single-panicle rows to obtain F3. In this generation, all lines that do not produce the desired characteristics, selected between and within lines, are eliminated. Within the selected lines, superior plants are chosen for sowing in rows, so that lines from clearly identified families are available.
In F4 either the complete family or lines from a family are selected. This is continued in F5, and in F6 as the lines are increased. Subsequently, the testing of the lines is done in multiple years and localities.
This method has yet not been utilized, although it has been proposed for obtaining durable resistance to Peronospora farinosa in quinoa (Mujica 1994).
The interest for quinoa as a crop which can be grown under very harsh climatic and edaphic conditions, providing a highly nutritious food product, is increasing. On the national level quinoa may help alleviate malnutrition in the Andean region, and may create incomes for the poor Andean farmers by satisfying the increased market demands nationally and from the export markets of the USA and Europe. For these reasons it is of utmost importance to characterize and conserve the genetic diversity existing, which will lead to diversified uses in the future. This is the key to securing the genetic diversity of the species and guaranteeing food security.
We kindly thank Dr David Brenner, Plant Production Station, Iowa State University, Ames, for commenting on the manuscript.
Aellen P. 1960. Chenopodium. In: Illustrierte Flora von Mitteleuropa, 2nd edn, vol. 3C, G. Hegi, Hanser, Munich, pp. 533-657.
Bonifacio A, Fairbanks D, Jacobsen SE, Blajos J, Stevens M, Jellen E. 2001a. Sustainable production of quinoa (Chenopodium quinoa Wild), a neglected food crop in the Andean region. Project proposal approved by the McKnight Foundation, Minneapolis, MN, USA.
Bonifacio A, Mujica A, Alvarez A, Roca W. 2001b. Mejoramiento genético, germoplasma producción de semilla. In: Mujica A, Jacobsen SE, Izquierdo J, Marathee J, eds. Quinua (Chenopodium quinoa Willd.)—ancestral cultivo andino, alimento del presente y futuro. FAO, UNA-Puno, CIP, Santiago, Chile, pp. 114-160.
Brenner DM, Widrlechner MP. 1998. Amaranthus seed regeneration in plastic tents in greenhouses. Plant Genetic Resources Newsletter 116:1-4.
Bukusov SM. 1965. Las plantas cultivadas en México, Guatemala y Colombia. Publicación Miscelanea Nº20 Instituto Interamericano de Ciencias Agricolas. Lima, Perú.
Danielsen S, Jacobsen S-E, Ames T. 2001. Impact of downy mildew on the yield of quinoa. In: CIP Program Report 1999–2000, pp. 397-401.
Gandarillas H. 1967. Observaciones sobre la biología reproductiva de la quinua. Sayaña 5:26-29.
Gandarillas H. 1974. Genética y origen de la quinua. Instituto Nacional del Trigo. Boletín informativo Nº 9, La Paz, Bolivia.
Gandarillas H. 1979. Botánica. In: Tapia M, Gandarillas H, Alandia S, Cardozo A, Mujica A, Ortiz R, Otazu V, Rea J, Salas B, Zanabria E, eds. Quinua y Cañihua, Cultivos Andinos. CIID-IICA. Serie de Libros y materiales educativos Nº 40 Bogotá, Colombia, pp. 20-33
Gandarillas H. 1984. Obtención experimental de Chenopodium quinoa Willd. Ministerio de Asuntos Campesinos y Agropecuarios IBTA, La Paz, Bolivia.
Gandarillas H, Tapia G. 1976. Epoca de siembra de la quinua. In: Segundo Congreso Internacional de Quenopodiáceas, Potosí, Bolivia. 26–29 abril. IICA, Serie informes de conferencias, cursos y reuniones Nº 96, Bolivia, pp. 21-23.
Jacobsen S-E. 1993. Quinoa (Chenopodium quinoa Willd). A novel crop for European agriculture. PhD thesis, Dept of Agriculture Science, Royal Veterinary and Agricultural University, Denmark, pp. 63-64.
Jacobsen S-E. 1997. Adaptation of quinoa (Chenopodium quinoa) to Northern European agriculture: Studies on developmental pattern. Euphytica 96:41-48.
Jacobsen S-E. 1999. Potential for quinoa (Chenopodium quinoa Willd.) for cool and wet regions of Europe. In: Proceedings of COST 814-Workshop: Alternative Crops for Sustainable Agriculture, 13–15 June 1999, Turku, Finland. BioCity, Turku, Finland, pp. 87-99.
Jacobsen S-E, Mujica A. 2000. New elaborated products from quinoa: protein concentrates and colorants. In: Proceedings of COST 814 Conference, Crop Development for Cool and Wet Regions of Europe, Pordenone, 10–13 May, Italy. European Commission, Luxembourg, pp. 517-520.
Jacobsen S-E, Risi J. 2001. Distribución geografica de la quinua fuera de los paises Andinos. In: Mujica A, Jacobsen SE, Izquierdo J, Marathee J, eds. Quinua (Chenopodium quinoa Willd.)—Ancestral cultivo andino, alimento del presente y futuro. FAO, UNA-Puno, CIP, Santiago, Chile, pp. 56-70.
Jacobsen S-E, Mujica A, Guarino L. 2000. The genetic resources of the Andean grain crop quinoa (Chenopodium quinoa Willd.). Proc. International Conference on Science and Technology for Managing Plant Genetic Diversity in the 21st Century, Kuala Lumpur, Malaysia, 12-16 June, 2000.
Jacobsen S-E, Repo R, Mujica A. 2001. El potencial de la quinua en la alimentación global. I Congreso Nacional de Industria Alimentaria “Visión al Futuro” (I CONIA), 23-27 abril, 2001, Universidad Nacional de San Agustin, Arequipa, Peru.
Johnson D. 1993. Blue corn and quinoa: New grain for the south-west. New Crops News 3(1).
Lescano L. 1994. Genética y mejoramiento de cultivos altoandinos. Programa Internacional de Waru Waru. Convenio INADE/PELT-COTESU, Puno, Peru, pp. 133-148.
Limburg H, Mastebroek HD. 1996. Breeding high yielding lines of Chenopodium quinoa Willd. with saponin free seed. In: Proceedings of COST-Workshop, 22-24/2 1996, KVL, Copenhagen. European Commission EUR 17473/KVL, Copenhagen, pp. 103-114.
Mujica A. 1988. Parámetros genéticos e índices de selección en quinua (Chenopodium quinoa Willd.). PhD thesis, Chapingo, Mexico.
Mujica A. 1993. Manual del cultivo de quinua. Proyecto TTA-AID-INIA, PIWA. Lima, Peru, pp. 32-46.
Mujica A. 1994. Esquema de la resistencia duradera de la quinua (Chenopodium quinoa Willd). In: Memorias del primer taller sobre resistencia duradera en cultivos alto andinos de Bolivia, Colombia, Ecuador y Perú, 30 Mayo-3 Junio, Quito, Ecuador, pp. 105-111.
Mujica A, Jacobsen S-E. 2001. Importancia de los factores abióticos adversos en la agricultura andina. In: Jacobsen S-E, Portillo Z, eds. Memorias, Primer Taller Internacional sobre Quinua- Recursos Geneticos y Sistemas de Producción, 10-14 May 1999, UNALM, Lima, Peru. CIP, Lima, Peru, pp. 169-174.
Mujica A, Jacobsen S-E, Izquierdo J, Marathee J. 2001. Resultados de la Prueba Americana y Europea de la Quinua. FAO, UNA-Puno, CIP, Lima, Peru.
Nieto C, Arroyo R, Jacobsen S-E, Peralta E. 2000. Investigación de tecnología apropiada para la producción de quinua organica en Ecuador. Project proposal PROMSA, Ecuador.
Ortiz R, Ruiz-Tapia EN, Mujica-Sanchez A. 1998a. Sampling strategy for a core collection of Peruvian quinoa germplasm. Theoretical and Applied Genetics 96:475-483.
Ortiz R, Stølen O, Christiansen JL, Madsen S, Jacobsen S-E. 1998b. Geographical and morphological pattern of variation defined a core collection of Peruvian germplasm. In: Proc. Research Council for Development Research and Centre for Tropical Ecosystems Research, Copenhagen, Denmark, 21 October, 1998, pp. 75-77.
Ortiz R, Madsen S, Ruiz-Tapia EN, Jacobsen S-E, Mujica-Sanchez A, Christiansen JL, Stølen O. 1999. Validating a core collection of Peruvian quinoa germplasm. Genetic Resources and Crop Evolution 46:285-290.
Partap T, Joshi BD, Galwey NW. 1998. Chenopods (Chenopodium spp.). IPGRI series: Promoting the conservation and use of underutilized and neglected crops, 22. IPGRI, Rome, Italy.
Pulgar Vidal J. 1954. La quinua o suba, alimento básico de los Chibchas. Economía Colombiana 1(3):549-560.
Rasmussen C, Jacobsen S-E, Lagnaoui A. 2001. Las polillas de la quinua (Chenopodium quinoa Willd.) en el Perú: Eurysacca (Lepidoptera: Gelechiidae). Revista Peruana de Entomología. 42:57-59.
Risi J, Galwey NW. 1984. The Chenopodium Grains of the Andes: Inca Crops for modern agriculture. Advances in Applied Biology 10:166-169.
Risi J, Galwey NW. 1989. The Chenopodium grains of the Andes: a crop for temperate latitudes. In: Wickens GE, Haq N, Day P, eds. New crops for food and industry Chapman and Hall, London, UK, pp. 222-234.
Rojas W, Barriga P, Figueroa H. 2000. Multivariate analysis of the genetic diversity of Bolivian quinoa germplasm. Plant Genetic Resources Newsletter 122:16-23.
Trognitz B. 2001. Mejoramiento de la quinua para resistencia a factores adversos. In: Jacobsen S-E, Portillo Z, eds. Memorias, Primer Taller Internacional sobre Quinta-Recursos Geneticos y Sistemas de Producción, 10-14 May 1999, UNALM, Lima, Peru. CIP, Lima, Peru, pp. 215-221.
Ward S. 1998. A new source of restorable cytoplasmic male sterility in quinoa. Euphytica 101:157-163.
Wilson HD. 1976. Genetic control and distribution of leucine aminopeptidase in the cultivated chenopods and related weed taxa. Biochemical Genetics 14:913-919.
Wilson HD. 1980. Artificial hybridization among Chenopodium species sect. Chenopodium. Systematic Botany 5:235-263.
Wilson HD. 1990. Quinua and relatives (Chenopodium sect. Chenopodium subsect. Cellulata). Economic Botany 44:92-110.
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