Toward an Evolved Concept of Landrace

Abstract

The term “landrace” has generally been defined as a cultivated, genetically heterogeneous variety that has evolved in a certain ecogeographical area and is therefore adapted to the edaphic and climatic conditions and to its traditional management and uses. Despite being considered by many to be inalterable, landraces have been and are in a constant state of evolution as a result of natural and artificial selection. Many landraces have disappeared from cultivation but are preserved in gene banks. Using modern selection and breeding technology tools to shape these preserved landraces together with the ones that are still cultivated is a further step in their evolution in order to preserve their agricultural significance. Adapting historical landraces to present agricultural conditions using cutting-edge breeding technology represents a challenging opportunity to use them in a modern sustainable agriculture, as an immediate return on the investment is highly unlikely. Consequently, we propose a more inclusive definition of landraces, namely that they consist of cultivated varieties that have evolved and may continue evolving, using conventional or modern breeding techniques, in traditional or new agricultural environments within a defined ecogeographical area and under the influence of the local human culture. This includes adaptation of landraces to new management systems and the unconscious or conscious selection made by farmers or breeders using available technology. In this respect, a mixed selection system might be established in which farmers and other social agents develop evolved landraces from the variability generated by public entities.

Back to beaked: Zea mays subsp. mays Rostrata Group in northern Italy, refugia and revival of open-pollinated maize landraces in an intensive cropping system

“…The bulk of genetic diversity in crops is found in landraces (Camacho Villa et al, 2006; Zhou et al, 2015), defined as: “plant materials consisting of cultivated varieties that have evolved and may continue evolving, using conventional or modern breeding techniques, in traditional or new agricultural environments within a defined ecogeographical area and under the influence of local human culture” (Casañas et al, 2017). Additionally, crop landraces often show interesting adaptations towards marginal environments and pest resistance (Camacho Villa et al, 2006; Mikami, Carpentieri-Pípolo & Ventura, 2012; Mabhaudhi et al, 2016; Guzzon et al, 2017).…”

“…For these reasons, landraces are of key importance in increasing the eroded genepool of modern cultivars with the aim of adapting agriculture to climatic changes and achieving a more resilient and sustainable agricultural system (Veteläinen, Negri & Maxted, 2009; Warschefsky et al, 2014). Not only do landraces possess useful traits for crop breeding, but they are of immense heritage value, linked to local and traditional products, and should be preserved for their importance in enhancing food sovereignty and safeguarding cultural diversity (Pieroni, Pawera & Shah, 2016; Casañas et al, 2017; De Luca et al, 2018). …”

“…The prerequisite of on-farm conservation programmes is on the availability of inventories of landraces. These inventories are fundamental to designing national and regional conservation strategies and for monitoring the efficiency of conservation actions (Negri, Maxted & Veteläinen, 2009; Casañas et al, 2017). Moreover, landrace inventories are needed to understand the geographical pattern of landrace distribution which helps to guide the collecting missions of plant genetic resources (Perales & Golicher, 2014; Orozco-Ramírez, Perales & Hijmans, 2017).…”

“…Moreover, landrace inventories are needed to understand the geographical pattern of landrace distribution which helps to guide the collecting missions of plant genetic resources (Perales & Golicher, 2014; Orozco-Ramírez, Perales & Hijmans, 2017). According to some sources, over the last few years, in several European countries a process of reviving landraces has been instigated by farmers and consumers, associated with traditional food production and the cultivation of marginal areas (Koutsika-Sotiriou et al, 2010; Barthel, Crumley & Svedin, 2013; Casañas et al, 2017). Nonetheless, this process is not homogenous and it is likely to occurr only for some crops and/or in some areas, while in other situations abandonment of traditional genetic resources and the substitution of landraces with high-yielding modern cultivars are still major threats for agrobiodiversity conservation (Teklu & Hammer, 2006; Dyer et al, 2014; Quave & Saitta, 2016; Ardenghi et al, 2017).…”

Towards the Genomic Basis of Local Adaptation in Landraces

“…Moreover, there is a consensus that plant landraces are dynamic populations that may be particularly adapted to certain environments. Other features that are usually attributed to landraces are yield stability, adaptability to sustainable farming, and resilience to stress, although these characteristics are expected to be evident especially in low-input agricultural systems [6][7][8]. For instance, submergence survival in rice landraces was retained as a beneficial trait in local ecosystems [9].…”