The accessions provided by this subset (or nursery) unite late blight resistance and adaption to high-elevation tropics. This subset can also be utilized for further crop improvement resulting in new varieties or be used by farmers to increase production and productivity in mid-elevation tropics.

Breeding efforts of CIP’s potato breeding program using germplasm of wild species, landraces and improved material have resulted in the development of two advanced populations with specific adaptation to the most important agro-ecologies of the tropics and subtropics: the Highland-Tropics Adapted Late Blight Resistant Population and the Lowland Sub-Tropics Virus Resistant Population. The Highland-Tropics Adapted Late Blight Resistant Population combines high levels of resistance to late blight with economically important traits such as tuber yield, tuber quality, processing and improved adaptation to warm environments and mid-season maturity (90 day growing period under short day length conditions). The Lowland Sub-Tropics Virus Resistant Population contains clones with resistance to the most important virus diseases (PVY, PVX and PLRV) of potato and adaptation to warm, arid environments with early maturity under short days and mid-maturity under long days. To promote the exchange and evaluation of CIP’s advanced clones, 12 subsets of clones were created (Gastelo et al. 2014). These subsets or “nurseries” offer trait combinations such as adaptation to tropical, subtropical and temperate regions of different altitudes, tolerance and/or resistance to biotic and abiotic constraints as well as agronomic or tuber quality traits: for tropical highland environments, resistance to late blight and virus is combined with drought tolerance while for mid-elevation tropics late blight resistance is matched with heat tolerance and in case of subtropical highlands, late blight resistance goes with a short to medium growth cycle. Generally, the nurseries contain clones that have the potential to counterbalance the effects of increasing temperatures in both traditional and new areas of potato cultivation.

The Potato Highland Tropics Late Blight Resistant Nursery is part of the Highland-Tropics Adapted Late Blight Resistant Population.