Abstract
The anatomy and morphology of oat (Avena sativa L.) cv. 'Udycz Żółty' flowers and inflorescences formed at different copper levels (0, 5, 125 mg Cu/pot) was investigated. Considerable changes in the structure of the generative elements of oat flowers occurred under conditions of severe copper deficiency (Cu = 0): the stamens showed considerably smaller anthers, with changed shape; the anther chambers were significantly diminished in size and did not open after the formation of pollen; the pollen grains were sterile, deformed and of smaller dimensions. The pistils and ovules were also smaller; outgrowths on the pistil stigmas were smaller and of a different shape. A decrease in the dimensions of the inflorescences was observed in both early and later phases of development. In moderately copper-deficient plants (Cu = 5) the flowers were heteromorphic: functionally male - with great anthers and small pistils, functionally female - with great pistils and small anthers and hermaphrodite - with great pistils and anthers.