The Influence of Flower Structures on the Seeds Productivity of the Carrot Breeding Lines

The aim of the study was to examine the morphological diversity of flowers of male-sterile (CMS) and male-fertile breeding lines of carrot and its influence on seed setting.

In examined male-sterile carrot population stamens are transformed into petal-like structures of different shapes. It was observed that in some anther-like structures sporogenic tissue degenerates. It is supposed that decrease of seeds productivity of carrot breeding lines could be caused by morphological abnormalities of mother and father-parental flowers. Degeneration of pollen, the absence of endothecium, which is responsible for opening the anthers and growth of pollen tubes on the external area of the pistil, decreasing the number of functional pollen influence negatively fertilization. Moreover, other specific traits of male-sterile mother plants, as reduction of nectaries size, pistils deformation, ovule and embryo degeneration also inhibit process of seed setting. The lowest amount of seeds produced plants with multiple stigma pistils and nectaries deformations. Male-sterile plants with white flower petals, big nectaries, exposed, doubled pistils and big ovaries produced more seeds than the other mother plants.