Pollination, fertilization and fruit formation in eggplant (Solanum melongena L.)

Abstract

The aim of the investigations was to determine the regularity of pollination and fertilization as dependent on the phenotype of flower in eggplant. The experiment was conducted in 2005 and 2006 at the Agricultural University in Kraków, Poland. The object of the investigations was eggplant (Solanum melongena L.) 'Epic F₁', grown in the open field. Flower phenotype (long-, medium- or short-styled), fruit setting and the number of seeds per fruit were recorded on experimental plants during the flowering period. The number of pollen tubes in the middle of the style and the number on fertilized ovules in ovaries were evaluated for all types of flowers. The course of pollination was different in particular types of eggplant flowers. Differences concerned only the number of pollen tubes and fertilized ovules of short, medium- and long-styled flowers and the number of seeds in the fruit. There was not observed any incompatibility in the growth on pollen tubes in the styles of all types of eggplant flowers. Stereomicroscopy observations of cross sections of the ovaries do not show differences in the formation and position of the ovules on the placenta. Short-styled flowers were characterized by significantly lower pollination and fruit set efficiency and they produced fruits with a significantly lower number of seeds. The low number of pollen tubes, fertilized ovules and seeds can be a straight consequence of the morphology of short-styled flowers: small-sized stigmas and spatial separation of anther pores and stigmas, which makes pollination diffi cult.