122
These trials also function as living gene banks that maintain resources for future
genetic improvement and climate adaptation. Because some of these trials duplicate
species and germplasm sources across locations, they can provide information on
responses to environmental variation that is crucial for devising climate adaptation
strategies. However, further field experiments are required to properly understand
variation in AOCC species.
As well as the need for greater funding for perennial NOC improvement programmes, another key issue is the need to develop delivery systems that can provide
smallholder farmers in SSA with improved perennial NOC genotypes. Delivery to
smallholders of improved annual crops is also weak in the subcontinent and similarly requires improvement (see other papers presented in this book), but there are
specific additional issues faced by perennial trees that require adjusted approaches
to annual crops. These include: the wide variety of tree species involved; the range
of different possible germplasm sources available; the form in which material is
planted by farmers (generally not as seed but as seedlings); the time that trees take
to mature; the large amount of offspring that can be produced by any one tree; and
the generally low planting densities that are applied during cultivation, due to the
large size of mature individuals (Lillesø et al. 2017).
Developing improved germplasm and supporting the participation of small-scale
commercial providers, operating at local levels accessible to farmers, have been
identified as key for improving current tree crop delivery systems (Lillesø et al.
2011). Attention to climate-change trends and how these affect planting is also
crucial, especially as the longevity of trees mean that measurable changes in climate
at specific sites are possible within the life cycle of single generations (Alfaro et al.
2014). Climate planning requires that existing local providers are linked to suppliers
that operate over greater geographic distances, such as national tree seed centres.
The latter must coordinate the long-distance transfers, often working across countries, which are required to cope with the scale of climate-change trends. These tree
seed centres must then also interact effectively with local-level networks that have
lower transaction costs to reach farmers efficiently with climate-adapted tree planting material.
An effective delivery system for perennial crops requires a reorientation of the
current roles of different actors in germplasm supply (Lillesø et al. 2011, 2017). For
example, non-governmental organizations need to move away from using donor
support to supply tree planting material ‘for free’ to farmers—which inadvertently
out-competes local commercial suppliers and is an unstable short-term approach,
because of the vagaries of donor funding—to providing business and technical
training to support local supplier enterprises. Such reorientation is supported in
SSA by ICRAF and partners through training and decision-support tools (Kindt
et al. 2006). In addition, modelling ‘seed zones’ in current and future climates
(Kindt et al. 2016) helps to direct the larger scale translocations that are required for
adaptation, as illustrated by the case of the perennial NOC marula in East Africa in
Fig. 10.6. In this case, particular geographic sources of germplasm are likely to be
better adapted under future climates, meaning that these should be the focus of current collection and multiplication (compare Fig. 10.6a, b).
I. K. Dawson et al.
These trials also function as living gene banks that maintain resources for future
genetic improvement and climate adaptation. Because some of these trials duplicate
species and germplasm sources across locations, they can provide information on
responses to environmental variation that is crucial for devising climate adaptation
strategies. However, further field experiments are required to properly understand
variation in AOCC species.
As well as the need for greater funding for perennial NOC improvement programmes, another key issue is the need to develop delivery systems that can provide
smallholder farmers in SSA with improved perennial NOC genotypes. Delivery to
smallholders of improved annual crops is also weak in the subcontinent and similarly requires improvement (see other papers presented in this book), but there are
specific additional issues faced by perennial trees that require adjusted approaches
to annual crops. These include: the wide variety of tree species involved; the range
of different possible germplasm sources available; the form in which material is
planted by farmers (generally not as seed but as seedlings); the time that trees take
to mature; the large amount of offspring that can be produced by any one tree; and
the generally low planting densities that are applied during cultivation, due to the
large size of mature individuals (Lillesø et al. 2017).
Developing improved germplasm and supporting the participation of small-scale
commercial providers, operating at local levels accessible to farmers, have been
identified as key for improving current tree crop delivery systems (Lillesø et al.
2011). Attention to climate-change trends and how these affect planting is also
crucial, especially as the longevity of trees mean that measurable changes in climate
at specific sites are possible within the life cycle of single generations (Alfaro et al.
2014). Climate planning requires that existing local providers are linked to suppliers
that operate over greater geographic distances, such as national tree seed centres.
The latter must coordinate the long-distance transfers, often working across countries, which are required to cope with the scale of climate-change trends. These tree
seed centres must then also interact effectively with local-level networks that have
lower transaction costs to reach farmers efficiently with climate-adapted tree planting material.
An effective delivery system for perennial crops requires a reorientation of the
current roles of different actors in germplasm supply (Lillesø et al. 2011, 2017). For
example, non-governmental organizations need to move away from using donor
support to supply tree planting material ‘for free’ to farmers—which inadvertently
out-competes local commercial suppliers and is an unstable short-term approach,
because of the vagaries of donor funding—to providing business and technical
training to support local supplier enterprises. Such reorientation is supported in
SSA by ICRAF and partners through training and decision-support tools (Kindt
et al. 2006). In addition, modelling ‘seed zones’ in current and future climates
(Kindt et al. 2016) helps to direct the larger scale translocations that are required for
adaptation, as illustrated by the case of the perennial NOC marula in East Africa in
Fig. 10.6. In this case, particular geographic sources of germplasm are likely to be
better adapted under future climates, meaning that these should be the focus of current collection and multiplication (compare Fig. 10.6a, b).
I. K. Dawson et al.