Showing 5 results for Salicylic Acid
Latifeh Pourakbar, Latifeh Pourakbar,
Volume 15, Issue 2 (2-2015)
Abstract
Effects of decreased ozone and increased UV radiation have been studied by many researchers. The aim of this study was to investigate the effects of UV-B radiation on Melissa officinalis L. and to study the impact of salicylic acid and magnetic fields in reducing the harmful effects of radiation on plants. The Melissa officinalis L. plants were treated with 28_+2 Celsius temperature for about 60 days. The light intensity was 150 µ E mˉ² Sˉ¹ and the lightness-darkness condition was8-16 hours. UV treatment was applied after the six-leaf stage and UV-B radiation was applied for a period of 15 days, the time for each application was 20 minutes. Salicylic acid was sprayed on the plants after the six-leaf stage with a concentration of 1 mmol. Magnetic field treatment was applied for an hour with intensities of 0, 40 and 85 mT. The results indicated that the UV-B radiation led to reduction in dry and fresh weight, root elongation and shoots. The radiations also reduced the photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoid) and sugar rate and soluble proteins amount. The phenylalanine ammonia-lyase compounds rate and UV-absorbing compounds were increased under the effect of UV-B radiation. The results showed that treatment with salicylic acid and magnetic fields caused a reduced damage to the plant which had been created due to UV-B radiation and were able compensate for changed factors that had been changed because of UV radiation.
Volume 18, Issue 49 (11-2006)
Abstract
Salicylic acid (SA) is a compound that has a basic role in increasing cold tolerance in plants. When two-days old radish seedlings were pretreated with different concentra-tions of SA (0, 0.5, 1, 1.5 and 2 mM) for 24 hours and then imposed to cold stress at 2.5 ˚C for 48 hours, cold resistance is increased in them. This phenomenon is shown by reduced efflux of K+ ions and soluble sugars and increased root length of seedlings especially at 0.5 mM, SA concentration. This finding shows that there is a straight correlation between SA concentration and reduced cold injury. Measuring the activity of three antioxidant enzymes, ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and catalase (CAT) in shoot and roots of radish seedlings, revealed that SA induced cold resistance is accompanied by increased activity of these antioxidant enzymes.
Volume 18, Issue 49 (11-2006)
Abstract
The protective functions that have been ascribed to anthocyanins in leaves can be performed as effectively as can be done by a number of other compounds. Daisy plants (Bellis perennis L.) accumulat the anthocyanin of cyanidine 3-malonyl-glucuronosyl-glucoside in their leaves in the response of salicylic acid and pathogens. Results showed that the different concentrations (3, 7, and 11μM) of salicylic acid were effective. Salicylic acid have significantly reduced disease severity and the concentrations of 11 and 3 μM salicylic acid of increased amounts of anthocyanins in infected plants by Fusarium sambacinum and Alternaria spp. It can be concluded that the effects of salicylic acid on daisy plants results in the increased amounts of anthocyanins and the decrease of disease symptoms.
Volume 18, Issue 50 (10-2005)
Abstract
Neem (Azadirachta indica A.Juss.), native to the arid regions of Indian subcontinent, is a valuable tree because its fast growing rate and many technological importanc applications. We examined micrografting of the highly interested A.indica onto Melia Azedarach L. (Persian lilac) rootstock seedling, with the objective of estimating the resistance of this :::union::: to cold treatment afterwards. In these micrografting experiments the age of rootstock, the localization of graft and hormonal treatments during the time course of growth were examined under in vitro condition and after transfering to soil. The best shoot tips graft success was found on young rootstock(40.1%) in lateral hypocotyls position. Exogenous auxine in association with cytokinine was necessary to the best :::union::: and growth.In contrast effect of treatment increased amount of 18.33%in compare to control. If salicylic acid showed an inhibitory effect on the graft-take amount of 3% in compare to control,but salicylic acid treatment cause the highest grafting success amount of 8.33% in compare to control , signifying a useful role of salicylic pretreatment in acclimatization to soil conditions for these grafted plantlets.
Volume 18, Issue 57 (1-2004)
Abstract
Many different plant species synthesize triterpenoid saponins as part of their normal programme of growth and development. Examples include plants that are exploited as sources of drugs. Interest in these molecules stems from their medicinal properties, antimicrobial activity, and their likely role as determinants of plant disease resistance. Daisy (Bellis perennis L.) accumulates triterpenoid saponins in roots in response to salicylic acid (SA) and pathogens. The results of the research indicates that the amount of saponins in treated plants with SA was more than in the control plants. The amounts of saponins in infected plants and without SA was more than in the control plants. When infected plants were treated with SA, increases of saponins was shown in plants. The peaks observed in HPLC and their comparision with saponin standard confirm the results mentioned above. It is concluded that SA has significantly reduced diseases severity and increase the amount of saponins in infected and non-infected Daisy plants.
