Agriculture Reference
In-Depth Information
cultivars by exploiting thousands of elite breeding lines and improved
cultivars introduced from the International Rice Research Institute
(IRRI) and other sources, and crossing them with landraces and local
breeding lines originating in the ICA breeding program. The genetic
makeup of CIAT
working collection goes back to 1957
with the establishment of the Colombian rice breeding program head-
quartered in Palmira, Colombia (Martínez and Cuevas-Pérez 1995). In the
early years, the main objectives were breeding for resistance to rice hoja
blanca virus (RHBV) vectored by
Tagosodes oryzicolus
Muir, using
japonica
rice introduced from Asia and the United States as sources of
resistance. This breeding collection was enriched over time by the intro-
duction and use of genetic resources carrying genes associated with
agronomic traits that were important to the region. Cuevas-Pérez et al.
(1992) described the importance of 101 traditional landraces to irrigated
rice in LAC.
'
s rice breeders
'
B. Impacts of the CIAT Rice Breeding Program
'
CIAT
s Rice Program started its breeding work in Palmira, known as
a high-yielding environment with very low disease pressure. A man-
agement decision was made in 1982
-
1983 to evaluate and select breed-
ing populations under rainfed conditions in disease hot spots in
Villavicencio, Colombia, and Panama or Guatemala to increase resist-
ance to rice blast, grain discoloration, and
Rhynchosporium
,andto
breed for superior grainquality (Correa-Victoria andZeigler 1993)while
maintaining previous genetic gains. CIAT
s breeders used different
strategies, including pedigree and recurrent selection methods, anther
culture, interspeci
'
c crosses, composite populations, introgression,
and recombinant inbred lines, accompanied by a shuttle breeding
scheme, direct seeding and evaluation,andselectioninhotspotsfor
the main diseases, to broaden the genetic base of rice in LAC. Over time,
the focus changed from the development of
fixed lines with potential
to be released as commercial cultivars by national agricultural research
and extension systems (NARES) partners to precommercial breeding
(prebreeding). The idea is to develop and transfer to NARES improved
parental lines or populations that can be used to develop their own
genetically enhanced germplasm. These adjustments in
uenced the
kind of products and outputs delivered by CIAT
'
sRiceProgram.
CIAT
s research in rice has been vital for sustaining the productivity
and pro
'
tability of the rice sector in Latin America (Beintema et al.
2010). High-quality downstream research activities at the country level,
in close collaboration with strategic partners, were key to expanding
