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In production, shoot cuttings of lavender are most often used for vegetative propagation, however, this method does not promote high propagation rate. The most effective method is propagation by axillary or terminal buds that requires further plant rooting in vitro. Due to, objective of our work was analysis of lavender in vitro rhizogenesis. Investigation was performed on Lavandula angustifolia cultivars with different concentration of the growth regulators in medium. After18 Day, Only 1 mg/l NAA did not stimulate rhizogenesis for ‘Record’ and ‘Sineva’ cultivars. Root primordia formed from the cambium cells. Further root growth accompanied by cleavage of the core tissues and they appeared on the shoot surface. Morphologically, a root cap, meristem, elongation zone and zone with root hairs were identified in de novo formed root in vitro. Along with normally roots, the appearance of roots accreted along their periphery with free apexes and roots with the decreased meristem was also noted. For ‘Prima’ cultivar, highest values of the mitotic index were observed on the hormone-free half-strength MS medium and on ½MS medium with 1.0 mg/l NAA. Thus, our data showed that root morphogenesis for lavender cultivars depended on the plant material and culture medium.

Optimization of plants long-term conservation under in vitro conditions and identification of their structural and functional features during preservation is the basis for the creation of a genebank of cultured and wild plant species in vitro. The aim of our work was to study morphological and anatomical features of plants in lavender cultivar ‘Sineva’ after two years of in vitro storage at low positive temperatures. The plant material was evaluated after 24 months of conservation. A significant decrease in the linear parameters of leaves in the preserved plants was noted. Leaf shape altered from narrowly linear to oblong. With prolonged storage, the thickness of the leaf blade slightly increased. The integumentary tissues were thinner, compared with the plants cultured under standard in vitro conditions, the cuticle was not clear. The number of stomata decreased. The number of small vascular bundles decreased. The obtained data demonstrate viability of in vitro preserved explants, despite significant differences in structure, preservation of chlorophyll-containing tissues, a decrease in transpiration, and an increase of trichomes number. The stability of the vegetative organs functioning was revealed.

The article characterizes frost resistance of some winter-vegetating species of Oleaceae family in a climate of the Southern Crimean Coast. Olea europaea 'Nikitskaya', Ligustrum lucidum, Jasminum nudiflorum demontrate relatively high frost-hardiness. The realization of potential frost resistance depended both on weather factors associated with the air temperature fall down and on the weather conditions prevailing in the 10-day period preceding the date of frosty weather. High level of real water deficit during the winter period negatively affects the stability of O. europaea cultivars. In the studied species of the genus Ligustrum such correlation has not been revealed.

5.8S ribosomal RNA plays an important role in protein synthesis and eukaryotic ribosome translocation. Contact DNA insecticides based on antisense fragments of 5.8S ribosomal RNA gene of gypsy moth Lymantria dispar L. showed prospective insecticidal activity on its larvae. The most pronounced insecticidal effect was found for antisense fragments 10 and 11 nucleotides long (oligoRIBO-10 and oligoRIBO-11), whereas 12 nucleotides long fragment (oligoRIBO-12) caused the lowest level of insect mortality. This data corresponds to results obtained earlier using rabbit reticulocyte and wheat germ extracts, where maximum inhibition of protein synthesis was observed when a relevant oligomer 10-11 nucleotides long was used, whilst longer chain lengths resulted in reduced inhibition. Using oligoRIBO-11 fragment we have shown penetration of antisense oligonucleotides to insect cells through insects' exoskeletons. MALDI technique registered the penetration of the oligoRIBO-11 fragment into insect cells after 30 min and a significant response of insect cells to the applied oligonucleotide after 60 min, which indicates not only that the oligonucleotide enters the insect cells, but also the synthesis of new substances in response to the applied DNA fragment. Contact DNA insecticides developed from the L. dispar 5.8S ribosomal RNA gene provide a novel biotechnology for plant protection using unmodified antisense oligonucleotides. [ABSTRACT FROM AUTHOR]