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In most parts of Iran, the presence of water and soil salinity in urban area results in problems for grass growth. One way to solve this problem is the use of plant growth retardant, such as trinexapac-ethyl (TE), which is common and routine in turf management. This study was performed to investigate the response of Agrostis stolonifera L., Agropyron desertorum L. and Festuca ovina L., grown in sandy loam soil, to TE and irrigation water salinity. Resu-lts showed that spraying turf grass with TE increased most of the vegetative growth characteristics and content of chlo-rophylls, carotenoids and proline in clipping leaves, whereas increasing the NaCl concentration in irrigation water resu-lted in steady reduction in the values of these parameters, except carotenoids and proline content, compared with the co-ntrol group. Both TE and salinity treatments decreased the plant heights, as well as the fresh and dry weight of clip-pings. In the species which were studied, Agrostis stolonifera turned out to be the most tolerant turfgrass. Results also indicated that the application of TE enhances salinity resistance by improving the percentage of green leaf, chlorophyll concentration and proline content and reduce clipping in the species studied

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To understand the Eco physiological adaptation mechanisms of Fagus orientalis Lipesk to altitude changes, the activities of Peroxidase (POD), Catalase (CAT), and Ascorbate peroxidase (APX) in leaves of Fagus orientalis in different altitudes (A1: 700 m, A2: 1200 m, A3: 1700 m above sea level)  Was studied in the forests of Guilan. The sampling of leaves was collected from southern and northern parts of the crown of healthy and mature trees. The results of analysis variance showed that there was a significant difference between and within the population for the activity of catalase and peroxidase enzymes at the probability level of 0.05 and with increasing altitude, the activity of catalase and peroxidase were increased but the activity of Ascorbate peroxidase enzyme was initially increased and its level of activity decreased from the middle altitude with increasing altitude. Also, the results showed that the enzymatic activity of peroxidase and catalase in the northern leaves was more than the southern leaves that collected in crown of the trees.

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Yarrowia lipolytica, as a good cell factory to speed up the production of plant pharmaceutical components, has been considered to be one of the most important and attractive micro-organisms in recent years, due to its high secretion capacity, limited glycosylation, large range of genetic markers and molecular tools. Naringenin, as a central core of flavonoids production, plays important roles both in plants and in the treatment of different types of human diseases. For this purpose, specific naringenin biosynthesis genes from different origins were selected and introduced after comparative expression profiling in Y. lipolytica. This research indicated that chs plays the main role in the production of naringenin, so the increase copy number of this gene in each construct was investigated. The HPLC results confirmed that the construct with 5 copy numbers of chs resulted in 7.14 fold increase of naringenin extracellular titer to 90.16 mg/L in shake flask cultures. The results reported in this study demonstrated that sufficient knowledge of genes involved in the specific biosynthesis pathway, synthetic gene pathway and using Y. lipolytica as a capable and cheap host could help bioengineers to produce significant amounts of pharmaceutical components.