Investigations on fertilization fruit development and maturation in pomegranate (Punica granatum L. cv. Hicaznar)

This research was carried out to determine the biological, morphological and physiological properties of pomegranate cultivar Hicaznar which is widely grown in Antalya region. The research was carried out at Antalya Citrus and Greenhouse Crop Research Institute Serik-Kayaburnu Station, The Physiology Laboratory of the Department of Horticulture, Faculty of Agriculture, and Pathology and Histology Laboratories of Medicine School at Akdeniz University in Antalya between 1994-1995. Flowering, pollination, fertilization, embryo development, fruit development, fruit setting and growing characteristics of Hicaznar were studied Physical and chemical changes during fruit setting and fruit growth were also examined to determine optimal harvesting time. Experiments were made in both field and laboratory conditions. Pollinations were conducted in field conditions in order to see fruit and embryo development. After removing anthers and making pollinations, pollinated flower samples were taken at certain intervals and put into a fixative. Slides were prepared by using squashing and paraffin methods. It was observed that pollen tubes reached to ovary in 72 hours. In paraffin slides it was seen that endosperm in embryo sac was at free nuclei stage in 3 days after pollination. At the end of seventh day, embryo formation was completed. Experiments showed that there was a correlation between physical and chemical changes occured during fruit development and optimal harvesting time. Especially correlation between total soluble solid content and titratable acidity can be used in practice to determine optimal harvesting time. It was found that while red colour intensity in the skin was getting increased to became mature. In a similar way as arils got more reddish, total soluble solid content increased and titratable acidity in arils decreased. Single sigmoid curve was obtained fruit growing. In Hicaznar cultivar, 77.68% - 86.42% of total flowers in one tree were A type flowers, and 13.80%- III22.32% were B type flowers. The fruit setting of total flowers was 7.59% - 16.07% and 44.0% - 71.99% in B type flowers. KEY WORDS: Pomegranate (Punica granatum L.), flowering, fruit setting, pollination, fruit growth, pollen germination, pollen tube growth, embryo development.