| dc.description.abstract | Cacao production must increase in order to meet the projected rise in the
demand for chocolate. Approximately one-third of global production is lost annually
to diseases and insects. Four diseases account for the greatest losses worldwide:
black pod, caused by four Phytophthora spp.; witches broom, caused by
Moniliophthora perniciosa; cacao swollen shoot virus, caused by a member of the
genus Badnavirus; and frosty pod, caused by Moniliophthora roreri. At the present
time, only 30 % of material currently under cultivation is of improved varieties,
therefore, there is an urgent need for the development of new, high-yielding, diseaseresistant
varieties. Sustainable production increases could be achieved if improved
varieties were used by the farmers. Cacao breeding was started in Trinidad in the
1930s by F. J. Pound and within a few decades cacao research centers had been
established in all the major cacao producing areas worldwide including West Africa
and Southeast Asia. Pound and other researchers have made several expeditions to
the Amazon to collect wild cacao germplasm. In addition to using the germplasm
collected from the wild and farmers fields to find new sources of resistance genes,
researchers have developed breeding programs that cross and select cacao genotypes
in order to accumulate desirable genes for resistance, as well as good horticultural
and quality traits. Recently, numerous molecular tools, including the genome
sequences of two varieties of cacao, have been developed and/or made available
to accelerate the breeding process. International private/public collaborations are in
progress to identify candidate resistance genes, map these in the sequenced
genomes, and develop molecular markers associated with these genes. Researchers
will use these markers in genomics-assisted breeding programs to screen young
cacao plants and select those with desirable traits. | es_ES |
