Peculiarities of distant hybrid microsporogenesis in seed and stone fruit plants
The given data are dealt with cytological investigation of apple-pear and sour cherry-sweet cherry-bird cherry hybrids. The investigation has shown that meiosis in hybrid forms proceeded with significant disturbances. Deviations from normal process of reducing devision are observed in inability of chromosome majority to conjugate with each other, in formation of uni- polyvalents in guantitatively irregular and non simultaneous divergence of chromosomes, in formation of tetrads with disturbances and polyads. As a result of all these a great number of morphologically and genetically defective pollen grains are formed.