102
seasonal mean of 737 to 126 mm (International Potato Center 2017a). Potential
future impacts of climate change will exacerbate this trend (Zemba et al. 2013).
In Kenya, certified seed production meets approximately 5% of demand, which
has slowly increased from 0.6% in 2009 (International Potato Center 2016). The
majority of farmers obtain seed from informal sources or save a portion of their
harvest as seed for several generations. This is the case in most potato-producing
countries in SSA, where certification protocols are not put into practice. The low
yields plaguing this region (8–15 t/ha compared to realistic yields of 20–30 t/ha
obtainable under smallholder farmer conditions) are largely a consequence of farmers’ limited access to quality seed of biotic and abiotic stress tolerant climate-smart
varieties (Demo et al. 2015).
9.3.1.1 Climate-Smart Varieties
Climate change can be a major threat to potato production systems in Africa. In
many of the drier potato growing regions, climate change causes yields to decline as
a result of water and heat stress. Yields will decrease even further where there is no
possibility of irrigation, to the extent that growing potatoes will become impossible.
Traditional potato growing areas are also at risk of increasing temperatures; hence
varieties need to be heat tolerant. To adapt the potato to overcome these challenges,
breeding efforts by CIP prioritize resilience to the most likely future abiotic and
biotic stresses: heat tolerance, water use efficiency, earliness and disease tolerance.
In a series of adaptive participatory trials in several SSA countries, some climatesmart potato clones have shown great adaptability to erratic weather conditions.
With 15–20% less precipitation and a temperature increase of 2–3 °C under the
scenarios of climate change, these clones have shown greater tolerance to drought
and heat without yield losses (International Potato Center 2017b). This reduces the
risk of yield losses due to climate change, and offers farmers in mid-altitude regions
the possibility to integrate potato into their agrifood system.
From 2013 to 2015, 15 clones were evaluated for water-stress tolerance over
three seasons (2013–2015) at three locations ranging from 1300 to 1700 masl,
where seasonal precipitation averaged 295 mm (range 210–414 mm) and yielded
significantly greater than the existing varieties (Table 9.2, International Potato
Center 2017b). In 2016 and 2017, five of these biotic and abiotic-stress tolerant
clones with water-stress tolerance and enhanced resistance to late blight and viral
diseases were officially released in Kenya, specifically: Unica, Lenana, Wanjiku,
Chulu and Nyota.
9.3.1.2 Complexity of the Seed Potato Production System
Seed potato goes through physiologically different forms and rounds of bulking
before arriving at the final product. The first generation (G0) is the product of tissue
culture (TC) plantlets (the foundation and conservation material) in the laboratory.
M. L. Parker et al.
seasonal mean of 737 to 126 mm (International Potato Center 2017a). Potential
future impacts of climate change will exacerbate this trend (Zemba et al. 2013).
In Kenya, certified seed production meets approximately 5% of demand, which
has slowly increased from 0.6% in 2009 (International Potato Center 2016). The
majority of farmers obtain seed from informal sources or save a portion of their
harvest as seed for several generations. This is the case in most potato-producing
countries in SSA, where certification protocols are not put into practice. The low
yields plaguing this region (8–15 t/ha compared to realistic yields of 20–30 t/ha
obtainable under smallholder farmer conditions) are largely a consequence of farmers’ limited access to quality seed of biotic and abiotic stress tolerant climate-smart
varieties (Demo et al. 2015).
9.3.1.1 Climate-Smart Varieties
Climate change can be a major threat to potato production systems in Africa. In
many of the drier potato growing regions, climate change causes yields to decline as
a result of water and heat stress. Yields will decrease even further where there is no
possibility of irrigation, to the extent that growing potatoes will become impossible.
Traditional potato growing areas are also at risk of increasing temperatures; hence
varieties need to be heat tolerant. To adapt the potato to overcome these challenges,
breeding efforts by CIP prioritize resilience to the most likely future abiotic and
biotic stresses: heat tolerance, water use efficiency, earliness and disease tolerance.
In a series of adaptive participatory trials in several SSA countries, some climatesmart potato clones have shown great adaptability to erratic weather conditions.
With 15–20% less precipitation and a temperature increase of 2–3 °C under the
scenarios of climate change, these clones have shown greater tolerance to drought
and heat without yield losses (International Potato Center 2017b). This reduces the
risk of yield losses due to climate change, and offers farmers in mid-altitude regions
the possibility to integrate potato into their agrifood system.
From 2013 to 2015, 15 clones were evaluated for water-stress tolerance over
three seasons (2013–2015) at three locations ranging from 1300 to 1700 masl,
where seasonal precipitation averaged 295 mm (range 210–414 mm) and yielded
significantly greater than the existing varieties (Table 9.2, International Potato
Center 2017b). In 2016 and 2017, five of these biotic and abiotic-stress tolerant
clones with water-stress tolerance and enhanced resistance to late blight and viral
diseases were officially released in Kenya, specifically: Unica, Lenana, Wanjiku,
Chulu and Nyota.
9.3.1.2 Complexity of the Seed Potato Production System
Seed potato goes through physiologically different forms and rounds of bulking
before arriving at the final product. The first generation (G0) is the product of tissue
culture (TC) plantlets (the foundation and conservation material) in the laboratory.
M. L. Parker et al.