2026/07/02 by Natália Guimaraes, Ana Mautone, Alfredo Gravina +2 · 1 voice
Biochemistry, Genetics and Molecular Biology · Agricultural and Biological Sciences · #Plant Reproductive Biology #Plant and animal studies #Plant Physiology and Cultivation Studies
paper · pdf · doi:10.31285/agro.30.1914
openalex publication_date 2026/07/02 · openalex created_date 2026/07/03 · openalex updated_date 2026/07/04
Three promising new mandarin hybrids from the Uruguayan Citrus Breeding Program offer the organoleptic and quality standards demanded by the premium fresh citrus market. This study aimed to characterize the reproductive biology, parthenocarpic capacity, and field performance of F4P7, F3P8, and F2P3 genotypes to assess their suitability for seedless fruit production. For this purpose, pollen tube growth was evaluated under self-pollination, and potential limiting factors of fruit set and their type of parthenocarpy were evaluated. In addition, sprouting, flowering, and yield under open-pollination were studied. All three genotypes exhibited gametophytic self-incompatibility. Besides, these genotypes exhibited facultative autonomous parthenocarpy and low parthenocarpic capacity. Specifically, seedless fruits were produced only when compatible pollination was absent; moreover, parthenocarpic fruit set was not stimulated by self-pollination and remained lower than that observed under open-pollination conditions. Our results revealed that fruit set limitations were associated with insufficient GA₁ and soluble carbohydrate levels in the ovary during early fruit development. Cross-pollination significantly enhanced GA₁ levels and carbohydrate accumulation in the ovary, thereby improving fruit set and increasing the number of seeded fruits. Field performance showed year-to-year yield variability, with flowering intensity correlating with yield in F4P7 and F3P8. Conversely, F2P3 displayed more stable production and greater variations in shoot-type distribution across different flowering levels. Our findings highlight that preventing cross-pollination via bee-proof netting or spatial isolation is essential for seedless fruit production. In addition, agronomic practices aimed at increasing bioactive gibberellin levels and soluble carbohydrates availability are required to ensure consistent high yield in these genotypes.