[Cytogenetic investigation of geranium plants in tissue culture]. / Tsitogeneneticheskoe issledovanie rastenii éfiromaslichnoi gerani, poluchennykh v kul'ture tkanei.

Cytogenetic study of six cultivars and six selection lines of geranium (Pelargonium spp.), as well as of 100 plants regenerated from callus cultures has been performed. The majority of cultivars and lines had somatic chromosome numbers 2n = 7x = 56. Among regenerated plants of different cultivars (Rozovaja, Dushistaja, Krunk, Aist, Regar) obtained in vitro from various types of explants (internode, petiole) 61% of diploids and 39% aneuploids were revealed. Chromosome numbers in aneuploids varied from 46 to 82, among them 25.6% regenerated plants had 2n = 72; 10.2% -2n = 68; 5.1% -2n = = 64 and 12.8% -2n = 62. Addition of colhicine to nutrient medium increased the number of aneuploid plants.

[A morphological and karyometric study of the secretory cells in mint]. / Morfologicheskoe i kariometricheskoe issledovanie sekretornykh kletok miaty.

Morphological and karyometric peculiarities of oil-synthesizing secretory structures in mint forms differing by rate of oil biosynthesis were investigated. Significant similarity in morphology of secretory structures in investigated forms during differentiation and functioning was shown. Character of changes in karyometric properties of oil-synthesizing cells also was similar: nuclear and nucleolar volumes increased and then decreased during differentiation of secretory structures. A functional increase of nuclear and nucleolar volumes was found at the stage before essential oil secretion. Higher parameters at all stages of differentiation and before secretion were revealed in highly oil-production mint. This fact may serve as indirect indicator of increased functional activity of oil-synthesizing cells and intensity of oil-producing process. The obtained results are discussing with well-known data.

[Cytochemical study of the DNA and histone in the tissues of the lily anther in the course of microsporo- and gametogenesis]. / Tsitokhimicheskoe issledovanie DNK i gistona v tkaniakh pyl'nika lilii v khode mikrosporo- is gametogeneza.

The DNA and histone content in the microsporocytes, microspores, generative and vegetative cells of the pollen grain of Lilium candidum L., as well as in the anther wall tissues, was estimated by double wavelength cytophotometry. The lack of histone, as compared with DNA content, was demonstrated in the microsporocytes at the late premeiotic interphase and early meiotic prophase, as well as in the young microspores and anther wall tissues. The analysis of hydrolysis curves suggests the increase of non-condensed chromatin during endothelial cell differentiation.