LIBRO-CONGRESO-CITRUS

• Somatic hybridization
Plant somatic hybridization via protoplast fusion has become an important tool for ploidy manipulation
in plant improvement programs, allowing researchers to combine somatic cells from different cultivars,
species, or genera, resulting in novel allotetraploid and autotetraploid genetic combinations. This
technique can facilitate conventional breeding, gene transfer, and cultivar development by bypassing
some problems associated with conventional sexual hybridization including sexual incompatibility,
nucellar embryogenesis, and male or female sterility. The most important application of somatic
hybridization in plant breeding programs is the building of novel germplasm as a source of elite breeding
parents for various types of conventional crosses. In Citrus, somatic hybridization is being used to
generate key allotetraploid breeding parents for use in interploid crosses to generate seedless triploids
and for creation of new cybrids and asymmetric hybrids. Countries supporting programs based in this
technology include USA, Brazil, Japan, China, France, Italy, Brazil, New Zealand and Spain.
• Genomics
Due to the generally important heterozygosity of genitors and long juvenile period, the development of
markers for oriented introgression and early selection is a key point to improve the efficiency of citrus
sexual breeding. Clementine haploid sequence is available (www.phytozome.net) and the clementine
genetic map has been recently publicised. With these new tools citrus breeders will be able to survey
and comprehend the citrus genetic diversity with the objective to assist and enhance breeding programs.
• Genetic transformation
Genetic transformation allows the introduction of specific traits into known elite genotypes without
altering their genetic background. In the mandarin groups like clementines and satsumas, and due to
their highly heterozygous and complex genetic structure, genetic transformation should be considered
as a very promising tool for improvement despite of the negative social acceptance of these plants.
Advantages and disadvantages of the different procedures for different breeding objectives will be discussed
in the workshop, and also their relationship with the legislation related to essentially derived varieties, that
in some cases may preclude the protection of breeder´s rights of new varieties.
W03
Procedures for the exploitation of protected and/or patented varieties
Convener: Mercedes Iborra
Norma Agrícola. Rafelbuñol, Valencia (Spain). E-mail: miborra@normagricola.com
Since the early 19th century, the introduction of new varieties is an essential component to maintain and
sustain good and high crop productivity and quality. New varieties are constantly being bred for higher yields,
for better agronomic and quality traits like taste, and for resistance to abiotic and biotic stresses.
Plant Breeders’ Rights (PBR), also called Plant Variety Protection (PVP), is an exclusive right granted to breeders
of new varieties to exploit their varieties and has features that are in common with patents for industrial
inventions. Both forms of protection grant to their holders a form of exclusive right to pursue innovative
activity. With the PVP legislation, growers are in a better position to have access to new and improved varieties
for commercial growing.
Protection of a new variety is granted via a registration process based on validation of plant characteristics
that distinguishes it from other varieties. The condition for registration of new plant varieties and the granting
of breeder’s right is that the plant variety is new, distinct, uniform and stable. The scope of a breeder’s right
extends to acts carried out on a commercial basis including producing or reproducing, conditioning for the
purpose of propagation, offering for sale, marketing, exporting, importing and stocking the material for the
earlier activities. Hence, unauthorized conduct of such acts will constitute an infringement under the law.
Today practically all new citrus varieties are being protected, and their exploitation is being done following
different models:
16 - VALENCIA CONFERENCE CENTER, 18th-23rd NOVEMBER 2012