Records of the presence, importance and relative abundance of the phureja potato in Peru

Historical sources on ancient Peru were used, including the works of Varcárcel (1985), the report by J.B. Martinet at the end of the 19th century (Martinet, 1977), and the works ofHerrera (1921) and (Vargas, 1936; Vargas, 1946; Vargas, 1955), among others. Historical information was also gathered on one of the pioneers in potato conservation and genetic improvement in the Paucartambo region (Cusco). This is Mr. Yabar, recognized for his valuable work between the 1930s and 1945, during which time he promoted early practices of conservation and selection of local potato cultivars (Yabar-Villagarcía, 2004). Another key source was the database of Ochoa (2003), which contains information on passport data from native potato collections carried out in Peru between 1947 and 1997.

Information about ex situ conservation of the phureja potato in Peru

In 2020, a contact was established with personnel responsible for the potato collections of the experimental stations at the National Institute for Agrarian Innovation (INIA), the institution in charge of preserving the genetic resources of cultivated plants in Peru, located in the localities of Puno, Cusco, Junín, Ayacucho and Cajamarca. During this period, detailed information was collected on the number of accessions (units of genetic material) of phureja potatoes conserved in each station. This work allowed us to understand the practices and criteria applied for the conservation of this germplasm in different regions of the country. In addition, in 2023, the database of the International Potato Center (CIP) was accessed to obtain the number of phureja potato entries and those corresponding to Peru.

In Cusco, access was granted to the germplasm database managed by a group of communities there known as the ‘Parque de la Papa’, managed by the NGO Andes del Cusco Association. This database is an exhaustive register of native potato cultivars, including phureja varieties, conserved ex situ. Among these materials are samples repatriated from CIP, preserved in collaboration with local communities associated with the park. In addition, information was collected from the Regional Center for Andean Biodiversity Research (CRIBA) of the Universidad Nacional de San Antonio Abad del Cusco (UNSAAC), specifically on the number of native potato and phureja varieties stored in its germplasm bank.

In the city of Paucartambo, the Salcedo Rojas family coordinates the activities of the Paucartambo Conservationists Association. After an interview with two family members, we were able to access (for systematization and analysis) the database on native potatoes maintained by 30 conservationists from the districts of Paucartambo, Challabamba, Colquepata, and Huancarani. In addition, an interview was conducted with Julio Hancco, an outstanding conservationist from the community of Pampacorral, located in the province of Lares, who is widely recognized for his work in the conservation of agricultural biodiversity.

In the Cajamarca region, interviews were conducted in 2011 and 2021 with 20 potato conservation farmers in the provinces of Cajamarca, Celendín, Hualgayoc and San Marcos, previously identified in a study by Seminario and Zarpán (2011). The objective of these interviews was to determine the number of germplasm entries they maintain and to analyze the socioeconomic factors that affect their conservation work.

Information about in situ conservation of the phureja potato in Peru

The catalogues of native potatoes produced in Peru during the last two decades were compiled and analyzed. Those catalogues that specify the species to which the accessions belong or that, at least, record the duration of tuber dormancy were included. Although these documents do not provide direct information on cultivar erosion, the presence or absence of phureja potatoes in these collections is considered a relevant indicator of the level of conservation of this group on farmers' farms.

In Cajamarca region, information was collected on phureja potato collections carried out since 2005 in several provinces of this region. These data provided a comprehensive overview of the conservation efforts of potato cultivars and varieties by the communities. In addition, these activities made it possible to explore the challenges, strategies and traditional knowledge associated with in situ conservation, especially highlighting the crucial role of communities in the preservation of the genetic diversity of the phureja potato. Also in 2021, in the provinces of Chota and Cutervo, interviews were conducted with 45 potato farmers and information was collected on the phureja cultivars planted in the previous season and the varieties lost in the last two to three decades (Figure 1). In the locality of Waqanqa, located in the district of Paucartambo, Cusco, direct observation was carried out between 16 and 19 February 2020 with the objective of identifying potato cultivars. In addition, 16 farmers from the districts of Paucartambo and Challabamba, who participated in the XIX Agricultural Fair, held on 11-12 September 2023, were interviewed (Figure 1).

Empirical evidence on genetic erosion of the phureja potato in Peru

An exhaustive literature search for research related to the genetic erosion of the phureja potato was carried out, covering articles and other scientific publications produced between 1980 and 2023 that document the loss of native potato germplasm in Peru. For this purpose, physical libraries and bibliographic databases of wide coverage, such as Google Scholar, SciELO, Web of Science and Scopus, were consulted in order to gather and analyze information on this topic.

Presence, importance and relative abundance of the phureja potato in Peru

According to information gathered from existing literature, catalogues, germplasm banks and farmers' knowledge, the phureja potato is grown or present in 11 of Peru's 25 regions. These regions are mainly located in the Andean zone, at altitudes ranging from 2,000 to 3,500 meters above sea level (Figure 1).

Since ancient times, the phureja potato has been an essential source of food and a key component in the food security of Andean communities (Forbes, Charkowski, Andrade-Piedra, Parker, & Schulte-Geldermann, 2020). In ancient Peru, five types of potato were identified, classified in Quechua language according to their morphological characteristics and agroecological adaptations: hatun papa (large potato), chaucha [= phureja] papa (early maturing potato), maguay papa (early planting potato), capo papa (possibly qjapo papa, associated with elevated areas and dark soils) and chiri papa (potato cultivated in cold regions) (Varcárcel, 1985).

Herrera (1921) described the diversity and quality of potatoes in Paucartambo (Cusco), classifying non-bitter potatoes into four groups. Within the group of elongated potatoes, he included the chaucha or phureja potato, characterized by its rapid growth, watery tubers and reddish buds, although there were also varieties with round tubers and white buds. These potatoes have a cultivation cycle of approximately three months.Vargas (1936) also highlighted the importance of phureja potatoes in Paucartambo. These, known locally as papa nueva, mosoc papa or misca mahuay, are sown early and are used both for immediate consumption and starch extraction. In addition,Vargas (1946) gathered a collection of 774 potato samples mainly from Puno, Apurímac and Cusco, of which 79% corresponded to Solanum andigenum and 10% to Solanum stenotomum. Later, in Las Papas Sudperuanas, Parte II, Vargas identified four clones of chaucha potatoes (1206, 1207, 1208 and 1209) belonging to S. stenotomum, and one clone (549) classified within S. andigenum (Vargas, 1946).

Luis Á. Yabar Ordóñez (1886-1965), a horticulturist originally from Paucartambo, stood out as a pioneer in the conservation of native potatoes in Peru during the period from 1930 to 1945. Yabar compiled and maintained a valuable collection of approximately 250 native potato cultivars, including the churumpis, chauchas or phurejas, miskillas, thumillas, tokolos and phasñachas groups (Yabar-Villagarcía, 2004). His work was widely recognized by specialists in the study of this tuber. In 1944, J. G. Hawkes acknowledged his contribution by naming a species in his honour: S. yabari, which included two varieties, S. yabari var. pepino and S. yabari var. cuzcoense. These species were later reclassified as part of S. stenotomum (Ochoa, 1999; Watanabe, Baigorria, & Olcese, 2008).

A report from the mid-1940s noted that commercial potato varieties in Peru included chata blanca, chata rosada, chata negra, chata negra, amarilla, shitu, mauna and chaucha (Derteano, 1944). In the 1960s, C. Ochoa documented the presence of specimens of chaucha blanca, chaucha colorada and chaucha negra in the province of Sandia, Puno (Ochoa, 1964). Subsequently,Soukup (1970) described the chaucha potato or phureja potato as an early maturing variety characterized by its rapid cooking, even at the first boiling.

In Cajamarca,Iberico (1981) noted that the chaucha potato is distinguished by its characteristic colour, similar to that of egg yolk, as well as its extremely smooth texture and pleasant flavour. This tuber is commonly consumed parboiled and with skin.Leiva, Gonzalo, and Saenz (1990) documented its use in traditional medicine, specifically to relieve headaches. In this context, it is applied sliced with salt as a poultice on the temples, or ground in combination with olluco (Ullucus tuberosus), white corn (Zea mays), salt and vinegar for therapeutic purposes.

C. Ochoa, noted for his extensive potato collections between 1947 and 1997, collected a total of 322 phureja potato samples from 15 departments of Peru. These samples were organized according to their relative abundance as follows: Amazonas (140), Puno (52), Cajamarca (30), Ayacucho (28), Piura (16), Huánuco (12), Junín (11), Lima (11), La Libertad (6), Apurímac (4), Huancavelica (4), Ancash (2), Cusco (2), Pasco (1) and Lambayeque (1). These data reflect the distribution and prevalence of the phureja potato during this period. However,Ochoa (2003) noted that these samples were preserved only as herbarium specimens in various museums in Peru and other parts of the world.

Ex situ conservation of the phureja potato in Peru

In Peru, 6,295 native potato accessions have been identified in eight databases of working collections, including a university, a civil association and four experimental stations of INIA located in the Sierra (Table 1). Of these, only 0.3% correspond to the Phureja Group, which shows its minimal representation, even in the three main collections of the Cusco region, where its presence is insignificant. At the international level, CIP, which houses the world collection of potato germplasm, conserves only nine accessions of Solanum tuberosum L. Phureja Group from Peru, out of a total of 181 accessions of this species, most of which originate from Colombia and Ecuador (CIP, 2023).

The database of the Paucartambo Native Potato Growers' Association initially registered 2,500 cultivars. Each farmer maintains between 38 and 140 cultivars on average. Within this group, only two cultivars belong to the Phureja Group: Puka q'achirma and K'ello q'achirma. Both varieties are kept by a single farmer in the locality of Challabamba.

Julio Hancco, a well-known conservationist from Pampacorral, Cusco, reported that he had a collection of 350 potato cultivars, although none belong to the Phureja Group. He also reported having limited knowledge of this category of potato. Consistently, the analysis of the catalogue of a lot composed of 115 documented cultivars from his collection did not show the presence of cultivars of the Phureja Group either (Hancco, Blas, & Quispe, 2008).

In 2010, 20 conservationists of the Cajamarca Potato Producers Association dedicated to the conservation of native potatoes, including cultivars of the Phureja or Chaucha Group, were identified in Cajamarca. Of these, 17 maintained between 1 and 12 cultivars of the Phureja Group (Table 2). By 2021, the number of active conservationists decreased to 18, of which only 11 preserved between 1 and 10 cultivars of this group (Table 2). The total reduction in the number of native potato accessions in general and of the Phureja Group in particular was 50% and 52%, respectively.

The decrease in cultivars observed in 2021, together with the reduction in the number of active conservationists, is partly attributed to the advanced age of the latter, with an average age of 62 years, which limited their ability to continue conservation work. In addition, there were significant changes in the main economic activities of the conservationists: five focused primarily on livestock, four replaced agriculture with other occupations (such as carpentry, salaried work or temporary migration), three moved to urban areas while maintaining only partial agricultural activities, and one completely abandoned his activities due to chronic illness. Together, the remaining small collections total 35 accessions conserved ex situ in Cajamarca (Table 2).

In situ conservation of the phureja potato in Peru

Between 2006 and 2023, 27 regional catalogues of native potato were prepared, of which 19 met the established inclusion criteria. A total of 2,102 native potato accessions were identified in these catalogues, of which 4.3% correspond to the Phureja group (Table 3). Among the most outstanding catalogues are: Cuyo Cuyo (Puno), in the south, with 13 cultivars of the Phureja group (Wildlife Conservation Society , 2022); Huánuco, in the centre of the country, with 17 cultivars of phureja potato (Egúsquiza, 2015); and Cajamarca, in the north, which records 43 cultivars of Phureja. The Cajamarca collection was morphologically characterized, highlighting the first 15 accessions collected in three districts of Hualgayoc, which achieved a successful harvest (Figure 2) (Seminario & Zarpán, 2011; Seminario, Tapia, & Seminario, 2019). In addition, in 2021, in the Cajamarca provinces of Chota and Cutervo, 24 cultivars of Phureja planted in local farms during the last agricultural seasons were identified, and identified by their traditional names.

The exploration conducted in the community of Waqanqa (Paucartambo, Cusco) indicated that potato cultivation has been reduced in area and cultivars. No phureja potato cultivars were found. On the contrary, corn, apple and pasture crops stood out. Also, 16 farmers participating in the XIX Agricultural Fair of Paucartambo (11-12 September 2023), who were interviewed, indicated that they maintained between 2 to 250 varieties of native potato, and nine of them planted one to two chaucha cultivars (puka chaucha or k'ello chaucha). They mentioned that these potatoes had been lost due to lack of time to attend to the crop, because of their rapid sprouting and the scarcity of seed.

Empirical evidence of genetic erosion of the phureja potato in Peru

Genetic erosion in potatoes of the Phureja Group had its first documented evidence in Waqanqa, the largest community in the Mapacho river valley, in Paucartambo. This group of potatoes, traditionally cultivated in the region, showed a progressive disappearance since the 1960s, being reduced to only four or five varieties in 1987. Factors such as labour shortages, migration to urban areas and low local appreciation of these cultivars led to their replacement by improved varieties (Zimmerer, 1991; Zimmerer, 1992).

Canahua, Tapia, Ichuta, and Cutipa (2002) conducted a study in regions with extensive areas of potato and quinoa cultivation in six provinces of Puno. The results indicated that the cultivation of potatoes of the Phureja Group is restricted to small areas in the localities of Moho, Yunguyo and Viquechico. In addition, it was concluded that these cultivars are in danger of disappearing due to their low yields, despite being valued for their short maturity cycle and remarkable regeneration capacity.

Haan and Thiele (2004) documented a decline in the frequency of cultivation of cultivars of the Phureja Group in the district of Yauyos, Lima. This phenomenon was attributed to factors such as limited seed availability, low capacity for germplasm exchange, labour shortages, and farmers' increasing preference for more commercial cultivars such as ‘Huayro’ and ‘Peruanita’.

(CIP and FEDECH, 2006), together with Haan, Núñez, Bonierbale, and Ghislain (2010), conducted a study in Huancavelica on two potato groups, identifying the presence of 144 and 557 cultivars from four provinces and eight communities, but found no cultivars belonging to the Phureja Group. This absence was attributed to factors such as seed loss, temporary migration of inhabitants, substitution by modern cultivars and the lack of dormancy characteristic of this species. However,Brush, Carney, and Humán (1981) documented the existence of a single cultivar of Solanum phureja called ‘Pujuya’ in the community of Aymará, Tayacaja district, Huancavelica, known for its frost resistance and also cultivated by farmers in nearby regions such as Chongos Alto, in Huancayo, Junín.

The Ministry of Agriculture conducted research in the southeastern Junín department on native potatoes, identifying that it was currently difficult to find cultivars of the Phureja Group (MINAGRI, Grupo Yanapai, INIA and CIP, 2017). Similarly, Plasencia et al. (2018), in a study on the diversity of native potatoes in Challabamba (Paucartambo) and Quillcas (Junín), reported the presence of all the species studied, except S. tuberosum L. Phureja Group, although the causes of its absence were not determined.

Seminario and Zarpán (2011) andSeminario et al. (2019) estimated a 17% reduction in cultivars of the Phureja Group in five provinces of Cajamarca over the previous two decades. The main causes of this decline include the lack of time to attend to the crop, due to its short sowing and harvesting cycles; the preference of local communities for livestock activities rather than agriculture; the low quality of seed, which in many cases was depleted and with poor yields; the expansion of mining projects in the region; the trend towards the cultivation of modern varieties and more commercial native cultivars; labour shortages, caused by emigration and employment in non-agricultural activities; and the limited availability of seed for crop regeneration.

In 2021, a field study in the provinces of Chota and Cutervo (Cajamarca) revealed the loss of eight Phureja potato cultivars in the last two decades, reducing the total recorded from 32 to 24 (Table 2). The missing cultivars included Huevo de perdiz, Baya, Cemelina, Rosada, Morada, Negra, Chilopa and Amapola. The main causes identified are the rapid growth cycle of this group, which makes its management difficult; the preference for modern cultivars that are more competitive in the market; the prioritization of livestock; and the low quality of the available seeds, known as ‘tired seeds’. Currently, the remaining germplasm of Phureja potato in Cajamarca comprises 67 cultivars, of which 43 have been morphologically characterized in five provinces, while 24 are only nominally registered in Chota and Cutervo. It is essential to extend studies to other provinces to evaluate diversity and promote its conservation.