Sea buckthorn (Hippophae rhamnoides L.) genotypes of different ecological and geographical origins were tested. Frost hardiness extent was determined during winter by artificial freezing, which allowed identify varietal differences in frost hardiness of buds and tissues of sea buckthorn shoots. In order to identify differences in adaptation to low temperature we determined the fractional composition of water in annual shoots; and proline and malone dialdehyde concentration and total amylase activity in bark of shoots of female and male genotypes. In December, the sea buckthorn genotypes were in deep dormancy, when maximum frost hardiness of buds and tissues of annual shoots occurred. During the next months, the frost hardiness of buds and shoot tissues decreased during the state of exogenous dormancy. The performed experiment gave an opportunity to select hardy genotypes ‘Kenigsbergskaya’, ‘Surpriz Baltiki’, B 23-34, and ‘Prima Dona’ for use in further breeding, as they had demonstrated stable hardiness during the whole winter period according to all of the components of winter hardiness.
В результате исследований устойчивости сортов крыжовника к минусовой температуре выявлена их способность быстро проходить закалку в осенний период, что способствовало своевременному вхождению в период покоя. Проанализирован фракционный состав воды в их тканях в разные периоды закаливания. Установлено, что в тканях однолетних побегов в осенне-зимний период количество связанной воды увеличивается, а свободной-уменьшается. В процессе успешного прохождения закалки содержание сахаров во флоэме однолетних побегов повышалось. Оценен потенциал устойчивости к максимально низкой температуре, выявлены достоверные сортовые различия по морозостойкости почек и флоэмы однолетних побегов.
To study the effect of low molecular weight antioxidants on the respiration process, the content of auxins and abscisic acid, 15-day-old potato (Solanum tuberosum) tubers grown under laboratory conditions were sprayed with 5.8 μM sodium selenite solution or 0.1 mM caffeic acid solution. Control runners were treated with water. Hypothermia (-2 °C) simulating freezing was created for 2 hours. 21-day-old runners were analyzed. Under optimal temperature conditions, the studied antioxidants stimulated the respiration process, while selenite had a greater effect. Caffeic acid increased the maintenance respiration rate. Selenite and caffeic acid increased the auxin content in the runners. Selenite reduced the amount of abscisic acid, resulting in an increase in the indoleacetic acid/abscisic acid ratio. Under hypothermic conditions, caffeic acid significantly reduced the increase in respiration, and in the option with selenite, an insignificant stabilization of this process was noted with a greater decrease in indoleacetic acid/abscisic acid ration as compared with optimal conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.