100
Ralstonia solanacearum (a long surviving, soil-borne bacterial pathogen), and less
than 5% of farmers have access to quality seed (Gildemacher et al. 2009). However,
rates of food production can double, and possibly triple, without expanding the area
under production, by developing seed systems that deliver abiotic and biotic stresstolerant varieties.
We present two case studies that describe the introduction of climate-smart varieties of potato in Kenya and orange-fleshed sweetpotato (OFSP) in Mozambique,
and the associated challenges in their delivery through seed systems.
9.2 Challenges to RTB Seed Systems
Unlike true seed crops, RTB crops are vegetatively propagated crops (VPCs) and
their seed systems have received limited investment. Since VPCs tend to remain true
to varietal type for generations, farmers tend to save seed over several years.
However, there is a problem with this approach; multiplying the VPC seed without
acquiring fresh seed to flush through diseased stock can risk degeneration––the process when pests and diseases accumulate over successive cycles of propagation
(Bentley et al. 2016). More efficient seed systems that deliver climate-smart varieties and reduce the spread of disease are required to reduce the yield gap in RTB
crops.
As shown in Table 9.1, there are challenges to encouraging investment along
RTB seed systems, such as the bulky and perishable nature of the planting material.
Investment must therefore be focussed near the seed users who are often in isolated,
rural areas. Furthermore, the low multiplication ratios mean seed production is
more expensive and requires more time than for grain crops.
The benefits of climate-smart varieties can only be realized by addressing weaknesses in the delivery chain through functioning seed systems, directly linking seed
systems as a key tool to address climate change. The complexity of the production
and logistics systems must also be expertly addressed in order to speed up the delivery of well adapted varieties to markets.
9.3 Case Studies
9.3.1 Improving Access to Quality Seed of Climate-Smart
Potato Varieties in Kenya
Potato (Solanum tuberosum L.) is a key staple and fast expanding commercial crop
in SSA with more than 1.6 million hectares under production and five million potato
farmers (FAOSTAT 2017). In SSA and other tropical regions, potato production is
limited to the cooler highlands that lie between 1600 and 3000 m above sea level
(masl), and where night temperatures drop below the 16–18 °C required for
M. L. Parker et al.
Ralstonia solanacearum (a long surviving, soil-borne bacterial pathogen), and less
than 5% of farmers have access to quality seed (Gildemacher et al. 2009). However,
rates of food production can double, and possibly triple, without expanding the area
under production, by developing seed systems that deliver abiotic and biotic stresstolerant varieties.
We present two case studies that describe the introduction of climate-smart varieties of potato in Kenya and orange-fleshed sweetpotato (OFSP) in Mozambique,
and the associated challenges in their delivery through seed systems.
9.2 Challenges to RTB Seed Systems
Unlike true seed crops, RTB crops are vegetatively propagated crops (VPCs) and
their seed systems have received limited investment. Since VPCs tend to remain true
to varietal type for generations, farmers tend to save seed over several years.
However, there is a problem with this approach; multiplying the VPC seed without
acquiring fresh seed to flush through diseased stock can risk degeneration––the process when pests and diseases accumulate over successive cycles of propagation
(Bentley et al. 2016). More efficient seed systems that deliver climate-smart varieties and reduce the spread of disease are required to reduce the yield gap in RTB
crops.
As shown in Table 9.1, there are challenges to encouraging investment along
RTB seed systems, such as the bulky and perishable nature of the planting material.
Investment must therefore be focussed near the seed users who are often in isolated,
rural areas. Furthermore, the low multiplication ratios mean seed production is
more expensive and requires more time than for grain crops.
The benefits of climate-smart varieties can only be realized by addressing weaknesses in the delivery chain through functioning seed systems, directly linking seed
systems as a key tool to address climate change. The complexity of the production
and logistics systems must also be expertly addressed in order to speed up the delivery of well adapted varieties to markets.
9.3 Case Studies
9.3.1 Improving Access to Quality Seed of Climate-Smart
Potato Varieties in Kenya
Potato (Solanum tuberosum L.) is a key staple and fast expanding commercial crop
in SSA with more than 1.6 million hectares under production and five million potato
farmers (FAOSTAT 2017). In SSA and other tropical regions, potato production is
limited to the cooler highlands that lie between 1600 and 3000 m above sea level
(masl), and where night temperatures drop below the 16–18 °C required for
M. L. Parker et al.