Domesticated 6,000–10,000 years ago in the Andean highlands of southern Peru [1, 2], the cultivated potato (Solanum tuberosum L.) has quickly become one of the major staple foods worldwide . With a global production of 377 million tonnes in 2016, for a total gross value of $111 billion, the potato is now the fourth most important food crop in the world, after rice, wheat and corn .
Current potato breeding efforts aim to improve yields, food processing qualities, resistance to abiotic stress (e.g. drought), and resistance to pathogens [5, 6]. In their search for traits of interest to be introgressed into S. tuberosum, breeders can rely on the large botanical diversity of potatoes encompassing 4 cultivated and 107 wild species , distributed throughout Latin America (Figure 1), from New Mexico to Patagonia [7, 8].
Being adapted to a broad array of environmental and climatic conditions, wild potatoes possess desirable agricultural traits, such as higher disease and drought resistance. Recent genomic studies in the potato clade (Solanum sect. Petota) indeed revealed the extraordinary diversity of wild potato germplasm available for potato improvement [9, 10].
My project deals with the reproductive biology of Solanum chacoense (Figure 2), a wild potato species whose genome was recently sequenced . In breeding research, S. chacoense is studied for its high capacity to resist to a wide range of pathogens, such as potato virus Y [12, 13], bacteria causing potato wilt [14, 15] and common scab [16, 17], or fungi responsible for potato black scurf and blackleg , and powdery mildew .
Solanum chacoense has also a peculiar secondary metabolism producing high levels of specific glycoalkaloid compounds, such as leptines and leptinines , that are particulary efficient against the Colorado potato beetle . This small herbivore insect (Figure 3) is a major potato pest that can completely destroy cultures by feeding on leaves. Effort is being made to better understand genes involved in those metabolic pathways [22, 23] and to introduce them into the cultivated potato [24, 25, 26, 27].
Being a diploid species, S. chacoense is also studied as an alternative model to the tetraploid cultivated potato for molecular and cellular biology, especially in plant reproduction research. For instance, in our research institute, S. chacoense has been used in the Cappadocia lab to decipher the mechanisms underlying S-RNase-based gametophytic self-incompatibility [28, 29, 30, 31]. The Geitmann lab, now at McGill University, used S. chacoense in their research about cytomechanics of pollen tube growth [32, 33, 34].
The Matton lab uncovered various proteins involved in reproductive signal transduction pathways in S. chacoense, including RALF peptides [35, 36], MAP kinases (missing reference) and receptor-like kinases [37, 38, 39, 40]. Our lab also produced large-scale transcriptomic , proteomic  and secretomic  studies about S. chacoense reproduction.
My PhD project aims at understanding how pollen–pistil interactions, especially pollen tube guidance, are involved in the reproductive isolation of wild potatoes, i.e. the mechanisms by which they avoid interspecific hybridization.