Background: Damask roses (Rosa damascena Mill.) are mainly used for essential oil production. Previous studies have indicated that all production material in Bulgaria and Turkey consists of only one genotype. Nine polymorphic microsatellite markers were used to analyze the genetic diversity of 40 accessions of R. damascena collected across major and minor rose oil production areas in Iran.
The hypothesis that the extracellular concentration of sugars helps regulate the acclimation of plant cells to cold was tested in this work. Suspension cultures were used to control the concentration of sugars in the medium supplied to barley cell cultures (Hordeum vulgare L. cv. Igri), replacing the medium daily to help maintain the concentration. Freezing tolerance and the levels of mRNA expression of the stress-response genes blt4.9 (coding for a non- specific lipid transfer protein) and dhn1 (coding for a dehydrin) were measured. Similar levels of freezing-tolerance and gene expression were obtained in the experiments as occur during cold-acclimation in the crown of the whole plant. In the cell cultures, cold (6/2 degrees C) did not induce an increase in freezing tolerance or in the expression of detectable levels of blt4.9 or dhn1 mRNAs when only 1 g l-1 sucrose was supplied. However, the cells in this low sucrose medium in the cold were not sugar-starved, indicating that this did not explain the failure of the cells to acclimate when grown in the cold environment. Ten g l-1 sucrose supplied to cells grown in the warm (25 degrees C) induced acclimation to freezing and up-regulation of expression of blt4.9 and dhn1 mRNAs. Osmolality of the medium did not explain this. Thirty g l-1 sucrose induced yet higher levels of freezing tolerance and of blt4.9 and dhn1 mRNAs in cultures grown in either the cold or the warm environment. The results implicate sugars in the regulation of cold acclimation
Agropyron desertorum and Lophopyrum elongatum were grown in a control environment or acclimated in high-salt (daily exposure to 75 or 150 mm NaCl for 6 d), cold (6/2°C for 14 d) or drought environments (watering withheld for 6 d). Lophopyrum elongatum was constitutively tolerant to salt and also acclimated more to salt than did A. desertorum whereas A. desertorum acclimated more to cold and drought. Dehydrin and non-specific lipid transfer protein (nsLTP) mRNA sequences and polypeptides increased more, during acclimation to cold and drought, in A. desertorum than in L. elongatum crowns. Expression of immunologically identified dehydrin polypeptides was much higher in drought-acclimated A. desertorum than in any other species/treatment combination. The most strongly expressed were 42 and 20 kDa. No change in dehydrin or nsLTP polypeptides were detected in the crowns during acclimation to salt. Overall, there was stronger acclimation to dehydrative stresses, at the molecular level, in A. desertorum than in L. elongatum crowns. Differences in dehydrin and nsLTP mRNA and polypeptide expression during acclimation to different stresses indicated that plants sense the differences between different primary potential causes of cellular dehydration.
This effort aims to set new record and study the activities of two metabolically important distinct antioxidant enzymes, superoxide dismutase (SOD) and amylase in leaves and twigs of Damask rose (Rosa damascena Mill.). This research is done in various seasons to trace the seasonal shifts in plant metabolism. The results of our experimental work would be indicative of the seasonal variation patterns of R. damascena accessions in the concentration/activity of the estimated enzymes, which would in turn determine their functional importance in two types of tissues. SOD and amylase activities of leaves changed annually in the same condition and the first year had higher activities than the second year, except Kerman and Kermanshah. The content of SOD in leaf showed the strongest levels at 50% flowering in spring and the lowest ones were cleared in summer. The highest amylase levels were obtained at the warmest time in summer, while the lowest levels were obtained in autumn. These results elucidated that SOD activities were stronger than amylase activities among accessions in three phenological stages. There were evident differences between SOD and amylase activities in tissues. So, results elucidated that SOD activities in twigs were higher than leaf except in Kerman1 and Kermanshah1. Meanwhile, this research showed the strongest amylase activities in leaf. Enzyme activities in twig expressed variation among accessions and four phenological stages with high interactions. Overall, results determined that SOD activities were highest in comparison to amylase in twig.
The present study aimed to investigate the antioxidant activity of the various tissue types in Rosa damascena and determine the seasonal variations. The existence of statistically significant differences in the specific activities of enzymes among R. damascena accessions and tissue type was observed annually. The content of enhanced peroxidase and catalase in leaves has been shown to undergo seasonal changes with relatively low levels on young leaves in spring and strong activities on mature leaves in autumn. Meanwhile, the expansion of season from spring to winter showed a decrease in twig peroxidase activity, but catalase activities enhanced before raining in the autumn and then it decreased. Based on the results, R. damascena tissues, such as leaves and twigs indicated different responses including activation of antioxidative enzymes to seasonal change and during acclimatization to environment. There were significant differences in the specific activities of enzymes among R. damascena accessions.
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.