Agriculture Reference
In-Depth Information
(pedigree selection) on locally created populations through hybridiza-
tion of two or more breeding lines or cultivars.
Introduced genetic material consisted of cultivars, advanced breeding
lines, and segregating populations (as early as F
1
from three-way crosses)
developed by international research centers, mainly by CIAT, and
released by the national research institute. Germplasm introduced
from international centers has also been used intensively as parents
in local crossing programs. Most local cultivars were developed through
the pedigree method, although INIPA
s Rice Program used the bulk-
pedigree (bulk selection until F
4
and pedigree selection from F
5
to F
7
)
method for several years before switching to single-plant selection
(Table 5.5). INIPA also used dihaploidization of F
1
populations (through
anther culture, in collaboration with IRRI) and mutation techniques and
started a hybrid rice program during the 1980s, but eventually such
approaches were abandoned because of budget restrictions without any
output being obtained.
Most cultivars were released by the national research institute, but
some domestic private companies also developed and released rice
cultivars, such as Urpi, Taymi, Amor, and IDAL 186, with the latter
being the most successful.
'
G. Rice Breeding in Central America
In Central America, all countries (Guatemala, El Salvador, Honduras,
Nicaragua, Costa Rica, and Panama) grow rice to a greater or lesser extent
and have some kind of national rice program, for which genetic improve-
ment is one of the major research activities.
Central America produced 0.45% (2.7 million tonnes in 2004) of the
total world rice (Rivas Ch. 2008). This level has been constant since
1996, and Costa Rica (27%), Nicaragua (29.4%), and Panama (31%)
represent the main producers of the region. In 2011, the planted area was
88,168 ha in Nicaragua, 81,116 ha in Costa Rica, and 102,649 ha in
Panama (FAOSTAT 2012); whereas per capita annual consumption
was 45, 53, and 72 kg, respectively (FAO 2004).
Central American countries can be clustered into three groups based
on rough rice yield per hectare (Benavides and Segura 2005). El Salva-
dor, with yield of
6tha
1
, has shown the best yield of the region since
1996, despite slight drops in 1997 and 2003. In 2004, this country
ranked 15th among 112 countries worldwide with the highest yield
of rice husk. Costa Rica and Honduras form the second group, for
which yield is
∼
4tha
1
. Grain yield for Costa Rica stalled in 1996
and stabilized around 4 t ha
1
in 2005. Finally, Panama, Nicaragua, and
∼
