Science - December 16, 2004

Indonesian speeds up hot pepper breeding

Breeding hot peppers is likely to improve thanks to a new protocol developed by PhD student Ence Darmo Jaya Supena at Plant Research International. The new system makes it possible to develop genetically pure pepper genotypes from immature pollen, thus speeding up the breeding process.

Hot pepper is the most important vegetable crop in Indonesia, but disease and pests hamper cultivation, causing considerable losses. To speed up breeding programmes that concentrate on resistance against diseases, Darmo Jaya Supena developed a new haploid technology for producing pure lines within one generation, rather than the usual seven.

The Indonesian concentrated on refining embryo formation from microspores (the immature pollen). It is important to select the right hot pepper buds, from which the anthers are taken for a carefully described treatment. The anthers shed a large number of microspores onto a culture medium, where they grow into embryos.

The plants that develop have half the usual number of chromosomes. By doubling the number of chromosomes of these haploid plants, as they are called, it is possible to produce genetically pure homozygous plants very rapidly. The method allows four to seven plantlets to be produced from each flower bud, amounting to 75 – 125 plants per 100 anthers.

Ence Darmo Jaya Supena graduates on Wednesday 22 December. His promotor is Professor Evert Jacobsen, chair of Plant Breeding. / GvM