Principles of Plant Genetics and Breeding

468 CHAPTER 26
3 The approach favors producers in developing countries
where the practice of low input agriculture is
prevalent, and farmers use highly adapted landraces.
4 Farmers are able to select for traits they actually need
that may not be appealing to plant breeders.
Disadvantages
1 Including farmers in the decision-making process
may be time-consuming.
2 Several cultivars are released simultaneously.
3 Replacing cultivars with new ones is not a straightforward
operation.
New approach to international–national
collaborative breeding
The IARCs devote resources to assisting national agricultural
programs to increase agricultural production by
developing improved cultivars for farmers. Generally,
the international–national collaboration has been, as
some have observed, “top-down”, whereby the international
programs develop new genotypes that are then
evaluated by national programs. From testing these
finished or near-finished products, the local breeders
recommend superior ones for release as cultivars for
local production. This trend of plant “introduction” has
the tendency to displace locally adapted cultivars.
In view of the preceding discussion, it is being
proposed that early generation breeding material be
evaluated by local breeders in developing countries as
illustrated by Cecarelli in the box in this chapter. This
approach will increase the chance of exploiting positive
G × E interactions. It will also make breeding programs
in developing countries more self-reliant. The needs of
small producers will be more effectively met, with the
release of cultivars that suit their specific production
package.
Concept of organic plant breeding
The concept of organic breeding is relatively new and
less developed than the concept of participatory plant
breeding. Organic agriculture is simply agricultural
production without the use of synthetic inputs (e.g.,
pesticides, fertilizers, herbicides). To achieve this, organic
producers apply agroecological principles that promote
the self-regulating capacity of the agroecological system
(i.e., self-regulation of the soil, plants, and animals).
Issue of “naturalness”
Organic production is also described as the “natural”
way of production (alluding to the absence of synthetic
inputs). Some researchers insist that naturalness of
organic agriculture should not be limited to the absence
of synthetic inputs, or adherence to ecological principles,
but also to an acknowledgement of integrity and
wholeness in the production system. The concept of
integrity implies a belonging to a specific natural entity
(just like the concept of species that can freely interbreed,
but are genetically separated from others belonging
to another natural group).
To be organic, this naturalness must be accorded
proper consideration in how plants are propagated, cultivated,
or genetically manipulated to be in conformity
with the ideals of true organic agriculture. Further,
plants are ascribed an intrinsic value that indicates that
they are ethically relevant (in accordance with the attitude
society has towards nature).
Need for organic plant breeding
Organic plant breeding is a relatively new concept of
crop improvement. Currently, organic crop producers
depend on seed and other propagules that are developed
by conventional breeding procedures. If the integrity of
an organic production system is to be maintained, the
planting material used to initiate production should
have organic origin.
There are several reasons why organic breeding is
needed to service the organic production industry:
1 Genetically modified (GM) crop varieties are not
allowed in organic crop production. However, the
trends in the production of some crops are to use GM
seed or other materials. Efforts should be made to
develop non-GM varieties for organic production.
2 Crop cultivars suited to organic production are different
from those suited to conventional production.
Successful cultivars should be adapted to specific soil
and fertility conditions, be disease- and insect pestresistant,
and be competitive against weeds. Organic
producers rely on the natural fertility of the soil to a
large extent, hence the need for cultivars that optimally
interact with existing conditions. Crop cultivars
with architecture and structure that reduce disease
incidence are desirable.
3 There is a need to preserve the integrity of plants.
Conventional plant breeding methods sometimes
violate natural barriers (genetic engineering, wide
crosses) and consequently the integrity of plants.