Principles of Plant Genetics and Breeding

EMERGING CONCEPTS IN PLANT BREEDING 465
located in a low rainfall area. Therefore, the first step indicated that there is much to gain, and nothing to lose, in implementing a
decentralized participatory plant breeding (PPB) program.
Step 2: methodology
The second step was mostly about methodologies and consisted of the implementation of the breeding plan, the choice and testing
of experimental designs and statistical analysis, the refinement of farmers’ selection methodology, and eventually in initiating
village-based seed production activities.
From a breeding point of view, the major features of the second phase were: (i) a different role of the two research stations, one
of which was not used, while the second, located in an area with more reliable rainfall, was used for seed multiplication; (ii) an
increase in the number of farmers involved in the project; and (iii) the initiation of village-based seed production. The details of
the second phase, such as number of lines, plot size, type of germplasm, selection criteria, and seed production issues, were discussed
in meetings with farmers in each village. The host farmers and a number of neighbors attended these meetings, which
were organized by the host farmers. In the case of the type of germplasm, the farmers generally expressed preferences for the
seed color (black or white) and the row type. In one village, farmers wanted to test the breeding lines in two different rotations
(barley–barley and vetch–barley), and in another village in deep and shallow soil.
The model of plant breeding we use in Syria and in a number of other countries is a bulk pedigree system, in which the crosses
are done on the station, where we also grow the F 1 and the F 2 , while in the farmers’ fields we yield test the bulks over a period of
3 years (Figure 1). The testing starts from the F 3 bulks in trials called farmer initial trials (FITs), which are unreplicated trials with
165 entries, five common checks, and 30 systematic check plots (with one or two check cultivars). This allows the evaluation of
165 new breeding materials every year.
In parallel, we conduct on-station pure-line selection by collecting heads within the F 3 bulks selected by the farmers. The F 4
head-rows are promoted to the F 5 screening nursery only if farmers select the corresponding F 4 bulks. The process is repeated in
the F 5 and the resulting families, after one generation of increase, return as F 7 in the yield testing phase. Therefore, when the
model is fully implemented, the breeding material that is yield tested includes new bulks as well as pure lines extracted from the
best bulks of the previous cycle.
The breeding materials selected from the FITs are yield tested for a second year in the farmer advanced trials (FATs), which are
grown by between four and eight farmers in each village. Within a village the FATs contain the same entries, but the type and the
number of entries and checks varies in each village. The number of FATs in each village depends on how many farmers are willing
to grow this type of trial. Each farmer decides the rotation, the soil type, and the amount and time of application of fertilizer.
Therefore, the FATs are planted in different conditions and management systems. During selection, farmers exchange information
about the agronomic management of the trials, and rely on this information before deciding which lines to select. Therefore, one of
the advantages of the program is
that the lines start to be character-
On station
On farm
Crosses
F 1
F 2 bulks
Farmer
initial trial
Farmer
initial trial
Farmer
initial trial
Farmer
advanced trials
Farmer
advanced trials
Back to formal breeding for crosses
Farmer
elite trials
Adoption
Release (?)
Figure 1 The scheme of decentralized participatory barley breeding implemented
in Syria.
ized for their responses to environmental
or agronomic factors at an
early stage of the selection process.
The entries selected from the
FATs are yield tested for a third
year in the farmer elite trials
(FETs), which are grown by
between four and eight farmers
in each village. These entries are
also used on station as parents
in the crossing program. The three
types of trials are planted by scientists
using plot drills and are
entirely managed by the farmers.
During selection some farmers
are assisted by a researcher
(Figure 2). Some farmers select at
various stages but the majority
make their selection when the
crop is close to full maturity.
Using a scoring method from 0 =
discarded to 4 = most desirable,
farmers express their opinion on
each individual entry.