EN
Regeneration of cucumber from leaf explants resulted in a new species phenotype designated mosaic (msc).It is characterizes by two types of spots on teh leaves (zucchini-like and chlorophyllous) and has many altered morphological and physiological properties including slower growth, smaller organs, poorly germinating or empty seeds and smaller number of flowers per node.In msc plants the shape of the first leaf is always altered, and in about 76% of the flowers the crown is reduced and distorted to a varying degree.Chloroplasts of the zucchini-like sectors are filled with large starch grains, and some of the embryos die at various stages of development.The msc phenotype is ransmitted uniparentally only by the male plants and no segregation is observed in the F2 and subsequent generations.Possible mechanisms responsible for msc phenotype and its transmission are discussed.