This article presents the summarized data on cryopreservation of seeds of the medical plant Nepeta cataria. Cryopreservation is a highly promising method for saving of seed materials, allowing to organize long-term storage without viability loss. The purpose of present work is to optimize conditions of cryopreservation of seed materials of Nepeta cataria. Assessment of seed survival rate in the storage showed a linear decrease in seed viability and energy of germination. After 30 months of storage at the low positive temperature (+5 ºC) in paper pack seed rate decreased to 12.0 % and energy of germination to 11.2 %; after 4 years of storage seeds lost viability. During conduction of research the type of container, condition of thawing, optimal moisture of seeds and cryoprotectants are optimized. The optimal container for cryopreservation in liquid nitrogen was plastic cryo tubes; defrosting at room temperature. The best seed rate is found at moisture 3 %; the best cryoprotectant was glucose, the optimal concentration was 15 %. The result of the research is used for creation of the long-term storage medicinal cultures’ seed bank in the liquid nitrogen.

This article is devoted to the study of the influence of cryopreservation on the preservation of sowing qualities of seeds of representatives of the genus Picea: P. asperata (Rough spruce) and P. pungens (Spiny spruce). As an alternative shock method of cryopreservation, the method of step-by-step 3-step temperature reduction was used 1 stage +4 °C, 2 stage –18 °C, 3 stage –196 °C liquid nitrogen. Additionally, the effect of 4 time intervals (1 hour, 24 hours, 72 hours and 168 hours) of step freezing on seed quality was investigated. To explain the results by photometry, the total carbohydrate content of the seeds is determined before the 3rd freezing step (cryo interaction). The analysis of the results of germination showed that the seeds of the studied species respond in different directions to the step cryo freezing. So, seeds of P. asperata germination in all tree experimental variants are higher on 4–32 % than in the control variant; and the maximum results are revealed in the variant with time intervals of 168 hours. For P. pungens seeds, the germination rates in experimental variants were on 18–22 % lower than in the control; and the largest germination rate of seeds among experimental variations are revealed in variant with interval 24 hours. The determination of the total carbohydrate content of the tested seeds at different cryogenic freezing intervals found that this indicator varied significantly depending on the time interval. The lowest values of total carbohydrates are found in variation with a time interval — 24 hours. The maximum total carbohydrate content is determined in a variation with a time interval — 1 hour. Correlation analysis between seed germination indices and total carbohydrate content established a high relationship between these indices. So, for P. asperata, the value of the Pearson coefficient was 0.86, and for P. pungens seeds — 0.91.

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The article examines the effect above critical low temperatures on the quantitative and qualitative composition of essential oil of Chamomilla reticuta varia «Podmoskovnaya». Seeds of the studied plant species were treated with ultra-low temperature (–196 ºC) before planting in open ground and the viability of the seeds was determined under laboratory conditions. Cryo processing was carried out by direct immersion of seeds in plastic tubes in Dewar vessels with liquid nitrogen. Cryoprotectants were not used. Cryo processing duration was 1 hour, 3 hour and step freezing. Step freezing of seeds was performed in the following sequence: 1 hour in the refrigerating compartment (+ 4 ºC), 1 hour in the freezing compartment (–8 ºC) and 1 hour in liquid nitrogen. In all cases of the experiment, a slow thawing regime was applied. After cryogenic exposure, the material was planted into open ground. Recovery of essential oil was carried out by hydro distillation on a Clevenger apparatus. The component composition of the essential oils was determined on a Clarus-SQ 8 gas chromatograph with a mass spectrometric detector. As a result of the study, it was found that the effect of ultra-low temperatures on the seed material of the Moscow Region chamomile did not negatively affect the quantitative and qualitative composition of the essential oil of the pharmacy chamomile. On the contrary, this method of treating seeds has had a positive effect on the quantitative composition of the essential oil during the growth of the plant and in some cases has even increased the percentage of certain components, such as αfarnesene, β-farnesene, spatulenol, cis-en-in-dicycloether.

Жизнеспособность семян сортов ромашки аптечной после криоконсервации В статье изучено влияние сверхкритических низких температур на всхожесть семян ромашки аптечной. В качестве материалов исследованы два сорта ромашки аптечной «Подмосковная» и «Карагандинская». Семена используемых видов подвергались заморозке в жидком азоте в два этапа с различной длительностью (24 ч и 7 сут) и оттаиванием (быстрое и медленное). После криообработки семена высаживали в чашках Петри и помещали в климатическую камеру для определения лабораторной всхожести. Было отмечено, что низкотемпературное воздействие положительно повлияло на всхожесть и энергию прорастания семян ромашки аптечной (сорт «Подмосковная»), особенно при заморозке длительностью в 7 сут при медленном оттаивании. Хуже перенесла криообработку ромашка аптечная сорта «Карагандинская». Также следует отметить, что всхожесть и энергия прорастания семян обоих сортов после глубокого замораживания превышала 50 %. Таким образом, криообработка семян в жидком азоте (-196 ºС) не оказала отрицательного действия на жизнеспособность семян ромашки аптечной обоих сортов. Данная методика пригодна для сохранения генетических ресурсов исследуемых видов.