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In order to the investigation on the effects of methyl jasmonate on the secondary metabolites of Calendula officinalis L., the plants were grown in a modified Hogland (1/2) solution and were treated with 50 and 100 µm methyl jasmonate. The results indicated that jasmonate treatment decreased lignin content of root but increased lignin content of shoots, in comparison with those of the control plants. However, total content of wall-bound phenolics of roots increased and those of shoots decreased by jasmonate treatment. Anthocyanin content of shoot, decreased by methyl jasmonate. Likewise, flavonoid contents of shoots in both treatments were lower than those of the control plants. Lipid peroxidation rate of roots and shoots did not show significant changes in jasmonate treatments, compared to the control plants. In both control and jasmonate treated plants, α- Cadinol was the most abundant essential oils component. Induction of α-Muureloene with specific antifungal properties in the jasmonate treated plants and increase of it along with increase of jasmonate concentration, suggested that jasmonate can be used in order to induce modifications in secondary metabolism pathway of Calendula officinalis, resulting to produce desired medicinal compounds.

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Salinity is among important soil stresses adversely affecting the process of nitrogen (N) fixation in leguminous plants in different parts of the world. It has been indicated that salinity can inhibit the early stages of nodulation process between bacterium and the host plant including the exchange of signal molecules (nod gene inducers). There has not been any research regarding the effects of nod gene inducers on the growth of alfalfa inoculated with Sinorhizobium meliloti under saline conditions. A growth chamber experiment was conducted to determine the effects of pre-incubation of S. meliloti with effective inducers of nod genes Luteolin, Methyl jasmonate and Genistein on the growth and N-fixation of two different alfalfa (Medicago sativa L.) cultivars (Yazdi and Hamedani) under salt stress. Nod gene inducers increased alfalfa growth and N fixation under normal as well as under salt stressed conditions. Yazdi cultivar showed to be more tolerant to salinity than Hamedani with a higher growth rate and N fixation. Luteolin was the most effective nod gene inducer on plant growth and N fixation under normal and as well under salt stressed conditions. The results suggest that pre-incubation of S. meliloti with effective nod gene inducers can improve alfalfa growth and N fixation under salinity stress.

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An efficient transformation system for the medicinal plant Portulaca oleracea was established using agropine-type Agrobacterium rhizogenes ATCC15834. Hairy roots were obtained directly from cotyledon leaves explants seven days after inoculation with the bacteria. The highest transformation efficiency was obtained from cotyledon leaves explants, and amounted to 53.3% within two weeks. Roots grew rapidly on solid growth regulator free ½ Murashige and Skoog medium and demonstrated characteristics of transformed roots such as fast growth and high lateral branching. Successful and stable transfer of rolB gene was illustrated by PCR using specific primers of the gene. The hairy roots showed an ability to synthesize natural and medicinal product, dopamine. Elicitation of dopamine production in P. oleracea hairy roots was tested using different concentrations of methyl jasmonate (0, 100, 150, 200 μM) and salicylic acid (0, 125, 250, 500 μM), added to the hairy root cultures during the late growth phase. The results showed that the various concentrations of the methyl jasmonate significantly increased the dopamine content, but, at concentration of 100 μM, its impact was the most pronounced. Salicylic acid had no significant influence on dopamine production in hairy roots of P. oleracea.

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The effect of Methyl Jasmonate (MJ, jasmonic acid methyl ether) at 10^-6-10^-3M concentrations on triticale kernels germination, seedling growth, changes in soluble carbohydrates content and composition, and activity of α-amylase was studied. MJ inhibited the germination of triticale kernels, possibly due to decreasing activity of α-amylase, leading to the depletion of soluble carbohydrates in both embryonic and endosperm tissues. In this way, MJ reduced starch degradation. A lower amount of soluble carbohydrates in germinating seeds decreased water uptake (between 24 and 72 hours of germination) and delayed seedling development. The above effect can be attributed to high concentrations of MJ in the incubation mixture (10^-3M, 10^-4M). MJ reduced the number of embryonic roots in 5-days-old seedlings in all examined concentration ranges.