Fecha de publicación: 10/03/2025 Fuente: ISHS (International Society for Horticultural Science) Post date: Monday 10 March 2025
Author:
ISHS Secretariat

Stefania Bennici is a researcher at the University of Catania (Italy), where she is investigating the molecular mechanisms of sterility in citrus to ensure the production of seedless fruits. In citrus species, seedlessness is one of the most appreciated quality traits, especially for fresh fruits. Most commercial citrus cultivars exhibit some level of parthenocarpy which, in combination with mechanisms of sterility that prevent fertilization, ensures the production of seedless fruit. Several citrus species such as pomelos, mandarins and mandarin-like accessions also show self-incompatibility (SI), a mechanism that prevents self-fertilization under the control of the S-ribonuclease (S-RNase), a highly polymorphic gene encoding a stylar protein that inhibits the growth of pollen tubes where the pollen grains are from the same plant or from plants with the same alleles. Knowing the S-genotype is important in selecting SI varieties to cultivate in blocks isolated from any cross-compatible pollen source. On the other hand, important citrus species such as sweet oranges, lemons or grapefruits may exhibit a self-compatible behavior that seems to be associated with the presence of a mutated S-allele (Sm-allele). In this case, a revert mutation of the Sm-allele could restore SI and consequently seedlessness in self-compatible genotypes. In her research, consensus primer-based PCR and Sanger sequencing were used to define the composition of S-alleles from a collection of 41 accessions belonging to different species and genera of the Rutaceae family, identifying 15 different S-alleles. Among them, five new alleles were identified. In addition, Stefania performed a CRISPR/Cas experiment to edit the mutated Sm-allele in the self-compatible sweet orange ‘Doppio Sanguigno’ with the aim of restoring SI and obtain a seedless sweet orange genotype. The next steps in her research will involve the phenotypic evaluation of fruit from self-pollinated regenerated edited plants. The results should facilitate the development of seedless citrus fruit in breeding programs using self and/or cross-incompatible pollen donors, selected by gene markers or using genome editing.
Stefania Bennici won the ISHS Young Minds Award for the best poster presentation at the XV International Citrus Congress in South Korea in November 2024.
Stefania Bennici, University of Catania, Dept. of Agriculture, Food and Environment, Via Santa Sofia 100, 95123 Catania (CT), Italy, e-mail: stefania.bennici@unict.it
The article is available in Chronica HorticulturaeTags: genome editingcitrusCategories: Young Minds Award Winners