Draft:Cañihua

Genetics

Cañihua is a member of the Goosefoot family (Amaranthaceae) and falls under the Chenopodium species, the genus comprises 150 herbaceous flowering plants. The plant belongs to the pseudocereals, similar to the increasingly popular quinoa (Chenopodium quinoa) and is closely related to it. Cañihua (AA, 2n = 2x = 18) is a diploid A-Genome relative of the allotetraploid quinoa (AABB, 2n = 4x = 36 ). Quinoa's genome represents a recent polyploidization event between North American and Eurasian diploid species donating the A and B subgenomes of modern quinoa, respectively. The South American Cañihua is not believed to be the direct A genome donor for Quinoa but a close relative to it.

Breeding

The pseudocereal is considered a semi-domesticated plant by many researchers. Initiating genetic enhancement efforts for cañihua is necessary for the continued or intensified cultivation of this crop. The plant shows morphologically weedy characteristics, non-uniform maturation, and tendency to sheed shattering. A further agronomic issue is the small seed size that makes harvesting and processing of the seed difficult.

Breeding goals are to  increase the plant height and non-shattering behaviour, among other characteristics. Since 2019 a whole assembly reference genome for cañihua is available and renewed interest in improving agronomic properties using modern plant breeding is expected by experts.

Domestication

Cañihua is considered a semi-domesticated plant by many researchers. Nevertheless, clear distinctions between wild and cultivated lines can be shown phylogenetically. Chenopodium pallidicaule was domesticated by the Tiwanaku culture, a pre-Columbian civilization that thrived in the Andean Altiplano. The lacustrine region of Lake Titicaca is considered the centre of origin – it is there where genetic variability in cañihua is still greatest. Morphological seed inquiries and bibliographic reviews suggest that domestication could have occurred 3'500 years before present. In archaeological sites remains of cañihua starches are found with an age of 5'000 to 3'200 years. Other sources date the cultivation as far back as 7'000 years. The exact history of domestication remains speculative.

After the Spanish Conquest cultivation of cañihua was discouraged due to its association with indigenous cultures. Today cañihua remains confined to Peru and Bolivia and the crop has not spread outside the arid highland regions. It is cultivated in the Peruvian Sierra zone and in the Altiplano of Bolivia, with the Punio department being particularly significant for cañihua cultivation.

Cultivars

In the Peruvian highlands approximately 50 different genotypes are sown. There are different ways by which cañihua varieties are differentiated and the naming may vary by region. A possible discrimination is by coloration of seeds or fluorescence into Wila (red), Q’illu (yellow), Janq’u (white), Chiara (black) and others. Another common classification involves distinguishing varieties by their growth habitat. Saiwa varieties display an upright growth habit, Last’as exhibit a semi-prostrate one, and Pampa Last'as have a prostrate growth habit, growing close to or along the ground. Saiwa types are well-suited for hillsides due to their lodging tolerance, while Last’as materials are preferable in plains. The majority of cultivated landraces belong to the Last’as type.

There are only a few improved landraces of or even cultivars of cañihua. In Peru, the National Institute for Agricultural Innovation (INIA) has selected four landraces with favorable agronomic characteristics: Cupis, Ramis, and Illpa INIA 406. In Bolivia there are three improved varieties belonging to the Last’as type: Kullaca, Illimani and the most resent Qañawiri. Improved landraces typically show outstanding yield and reduced risk of grain losses in the maturity stage and during harvest.

There is an ongoing conservation effort for the genetic diversity of cañihua in Peru. The germplasm banks of Camacani-UNA-Puno and Illpa-INIA-Puno currently house 430 unique samples from specific locations, accompanied by passport data and agronomic and morphological characterizations.