Abstract

Plants respond to adverse biotic and abiotic conditions within their local environment, whereby they use their remarkable ability to adjust their physiology to cope with and acclimate to changing growth conditions. Climate change threatens agriculture, increasing the loss of soil and reducing areas suitable for crop production systems; by 2050 it will be necessary to increase plant productivity by 70% to satisfy the needs of an ever-increasing world population (FAO 2019). Crop yield is largely determined by climate conditions, therefore minor deviations from optimal conditions can strongly penalize yield potential in terms of quantity, but also quality. Considering the agricultural challenges we face for the next coming decades, a deeper understanding of the effect of environmental factors on crop growth and development could significantly reduce yield losses and improve quality, ensuring food security worldwide. The development of new varieties with high and stable genetic potential for high density crop production is the main challenge for breeding and modern agronomy. However, there are contrasting views to achieve this goal. It has been highlighted that modern cultivars usually achieve higher yields with plenty of soil nutrients and optimal climate conditions. However, there are several reports indicating a better performance of landraces (genotypes adapted to local regions) compared to modern genetic materials, which generally may present low to medium yields. It has been accepted that the main contributions of landraces are traits related to adaptations to stressful environments, which can be used in plant breeding programs (Dwivedi et al. 2016). Since the 1960s, there has been plenty of evidence of a slowdown in yield improvement rates of major food crops (including rice, wheat and maize) (FAO 2016), and current yield strategies are not enough to meet future requirements (Lenné and Wood 2011). Considering that climate change will affect the potential of traditional crops, searching for ancestral crops and landraces with high genetic diversity and food potential is mandatory. Thus, landraces and wild relatives will be important genetic sources for developing new varieties with higher yields (in terms of quantity and quality) and enhanced stress tolerance. Latin-American crops comprise high diversity of plant species as they are adapted to a wide range of environments; this has resulted in large genetic pools and, therefore one of the richest repositories worldwide (Bazile et al. 2014). Several cultivars from this region have been widely explored, and many hybrids and improved varieties have been produced. This is the case of Zea mays (maize) and Phaseolus vulgaris (pea). However, other crops yet remain to be further explored, such as Amaranthus sp (amaranto or kiwicha), Chenopodium pallidicaule (cañahua), Chenopodium quinoa (quinoa), Salvia hispanica (chia), Plukenetia volubilis (inchi) and Lupines mutabilis (lupino andino or tarwi), ones that show great food potential and an unexploited capacity to resist different abiotic stresses that make them suitable to grow in marginal environments. Besides, wild accessions of these species will remain a viable source of germplasm, not only to maintain high productivity, but also to increase seed quality (FAO 2016).