فصلنامه فرآیند و کارکرد گیاهی
سال دهم شماره 3 (پیاپی 43، Aug and Sep 2021)

Plantago sp., as a valuable source of natural antioxidants, has diverse food and pharmaceutical applications. In this study, six different Iranian species of plantago were studied to determine their antioxidant activity as well as their total phenolic, flavonioid, flavonol, chlorophyll, carotenoids, and anthocyanin content. The highest total phenolic content (92.37 mg GAE/g DW) and total flavonoids (57.16 mg QE/g DW) were found in P. major, but the highest total flavonols (46.07mg RE/g FW) and carotenoids (0.13 mg/g DW) were detected in P. cornopus. The least 1,1-diphenyl-2-picrylhydrazy (DPPH) activity (0.66 mg/ml) was found in P. major. Also, total antioxidant capacity was in the following order P. major> P. cornopus> P. subulata> P. lanceolate ≥ P. maritima > P. ovata.  Preliminarily comparison of the Iranian plantago species identified them as good sources of phenolic compounds. Hence, P. major followed by P. cornopus rich in natural antioxidants may be recommended as food supplements and nutraceutical aims.

Damask rose (Rosa damascena Mill.) is one of the ornamental and medicinal plants. In this study, shoot explants were cultured on MS medium with different concentrations of IAA, 2, 4-D, BAP, Kin, Br (brassinosteroids), and Vitamin B1 (VB1) in two group tests. Protoplasts were isolated from leaves with the enzymes and osmosis of sucrose. The results were studied, after the fourth week. In test 1, the results showed that 1 mg l-1 IAA with 0.1 mg l-1 Br had the highest rooting (63.33%), 1 mg l-1 IAA with 0.1 mg l-1 VB1 had the maximum shoot formation (66.67%), and 1 mg l-1 IAA with 0.1 mg l-1 Kin had the highest callus production (19%). The concentration of 0.1 mg l-1 IAA with 1 mg l-1 of VB1 was suitable for rooting (40%), shoot formation (50%), and low callus (10%) simultaneously. The highest rooting (73.33%) was obtained by using 4 mg l-1 2, 4-D with 0.4 mg l-1 BAP. The maximum Callus formation, root, and shoot number produced by 0.4 mg l-1 IAA with 4 mg l-1 VB1. High protoplast isolated in 0.5% sucrose. VB1 and Br enhanced the effect of IAA on root and shoot emergence of Roses.

Since the role of salicylic acid (SA) in Aloe vera plants under salt stress is not yet clarified, this experiment was conducted to investigate the role of SA (100 and 500 μM) in photosynthesis, antioxidative capacity and ion homeostasis in salt acclimated (EC 6 dS/m) and non-acclimated Aloe plants against subsequent salt stress (EC 21 dS/m). Salinity exerted an adverse effect on the leaf dry weight, whereas foliar spray of 100 μM SA mitigated the salt-induced inhibitory effects on the plant growth, especially under acclimated conditions. While salt stress caused a significant increase in Na accumulation and a considerable decrease in K and Ca, higher levels of K/Na ratio was observed after SA treatment. SA application (100 μM) also alleviated the damage to PSII function induced by salt, contributing to the improvement of electron trapping under salinity. Furthermore, Aloe plants exposed to EC 21 dS/m exhibited an oxidative damage, determined by increased content of oxidants (hydrogen peroxide and malondialdehyde). In contrast, foliar spray of 100 μM SA increased CAT activity as well as carotenoids content, and reduced content of oxidants under salt stress. Consequently, under both salt-acclimated and non-acclimated conditions, SA at concentration of 100 μM was more effective in alleviation of salt stress in Aloe plants via the enhancement of photochemical activity of photosynthesis, the activities of antioxidant enzymes and the ratio of K and Na under salinity.

To understand the agrophysiological barley associated with flag leaf temperature and canopy light interception under salinity and zinc foliar application (ZnFA), a field experiment was conducted in a strip-plot design with three replications in Isfahan, Iran. Saline irrigation water in three levels [2 (low), 10 (moderate) and 18 (high) dS m-1] were applied as vertical factors. Three barley genotypes [‘Morocco’ (salt-sensitive), ‘Nosrat’ (semi-salt-tolerant) and ‘Khatam’ (salt-tolerant)] were arranged within the vertical factors. The horizontal factors were four ZnFA [Nano-ZnO, Zn-EDTA, simultaneous applications of (Nano-ZnO + Zn-EDTA), and water (control)]. With increasing  salinity, light interception (LI), maximal efficiency of PSII (Fv/Fm), chlorophyll content (SPAD), relative water content (RWC),  number of spike (NS), kernel number per spike (KNS), thousand-kernel weight (TKW), and grain yield (GY) decreased, but electrolyte leakage (EL), flag leaf temperature (FLT) and proline  increased. Nano-ZnO had the highest EL and the lowest FLT, RWC, NS and KNS. Zn-EDTA application provided the highest LI, RWC, TKW and GY, and the lowest proline. Minus zinc application (check) had minimum LI, Fv/Fm, SPAD and GY. The tolerant genotype had maximum LI, proline, SPAD, RWC, KNS and GY, and minimum FLT, EL, NS and TKW. Overall, it was concluded that Zn-EDTA can be as a proper tool for increasing barley yield under salinity stress conditions. Likewise, this study has highlighted the close relationships existing between GY with, TKW (r= 0.89**), KNS (r= 0.46**), RWC (0.45**), NS (r= 0.36**), FLT (r= -0.32**), EL (r= -0.21**), and SPAD (r= 0.20**). These findings indicated that these physiological traits could be key factors, tools for screening, and provide useful information about stress tolerance mechanisms, which could be useful to plant breeders for selecting and developing salt-tolerant genotypes.

By changing lifestyle recently many consumers prefer to use processed and ready food like frozen vegetables because of the fastest and easiest way. For this reason, a factorial experiment based on RCBD was designed with 3 replicates to investigate the effect of blanching and freezing method over time on frozen cabbage. Treatments including 2 blanching boil water (Bb) and steam (Bs) and freezing methods home frozen (Fh) and semi-commercial frozen (Fs) and finally packed and kept in the freezer for 6 months. The results showed that the main effect of blanching exhibited that vitamin C decreased in Bs, phenolic compound and antioxidant increased in Bs. The main effect of blanching, freezing and storage time showed that texture, decreased with Bs and Fs significantly and storage time did not affect the texture. Vitamin C, the phenolic compound, and antioxidant decreased in all storage time and freezing method did not affect them. The interactive effect revealed that cabbage quality in chemicals, antioxidant, texture, and nutrient value decreased over time, especially, after 2-month storage in all freezing and blanching method. This reduction can be prevented by proper blanching and freezing method, but it plays different roles for various parameters.

To better understanding, the physiological and biochemical mechanisms of Trichoderma longibrachiatum (TL) and spermidine (SPD) polyamine treatment on cadmium (Cd) tolerance phytoremediation in purslane (Portulaca oleracea) plant and the activity of anti-oxidants enzyme (CAT, APX, POX, SOD), hydrogen peroxide and proline content as well as determination cadmium accumulation in shoots, roots, soil and their ratio to each other, a factorial experiment was performed in a completely randomized design with three replications and three treatments. In the current study, mitigative roles of SPD and TL were assessed in Cd stressed Portulaca oleracea plants. SPD (1, 0.5, and 1 mM) was applied after 20 days of sowing on the branches and leaves of plants inoculated or without TL inoculating in the presence of Cd (0, 30, 60 and 90 mg.kg-1). Cd stress and coexistence with TL increased the activity of antioxidant enzymes and leaf soluble protein in purslane plants. Also, the application of SPD, especially at 0.5 mM, resulted in a higher increase in leaf protein under cadmium stress in inoculated plants. Proline parameter responds differently to TL. SPD application reduced the severity of these changes. The amount of H2O2 was significantly reduced in plants when treated by both TL and SPD. Significant differences were observed between 0.5 and 1 mM of SPD in terms of the Cd uptake in the TL inoculated purslane shoots. Inoculated purslane plants treated by either 0.5 or 1 mM of SPD had lower Cd uptake and greater BF. In general, the results showed a synergetic effect between TL fungi and SPD application on improving the Cd phytoremediation in the purslane plant.

The aim of this study was to determine the impacts of endophyte (E) inoculation on Nickel tolerance of the Lolium prenne by measuring the physiological and biochemical traits in two populations of ryegrass consisting both (E-) and (E+) plants cultivated under Ni stress. The plants were grown in a Ni polluted soil at 0, 30, 90 and 180 mg Ni kg -1. The present research showed that the activity of antioxidant enzymes increased in Ni treated plants in contrast to control plants; whereas the activity of glutathione reductase enzyme decreased. Also, endophyte infection increased the activity of some antioxidant enzymes but decreased the activity of SOD enzyme. Upregulation of aquaporin gene (LpTIP1;1) was shown in population 1 E+ plants at all treatments and 30 ppm Ni in E- plants, whereas, the expression of LpTIP1;2 in population 1 E- plants increased and no significant difference was shown for E+ plants. After 3 months from treating plants, considerable reduction in shoot biomass of E+ and E- plants was observed in 180 ppm Ni and endophyte inoculation decreased the biomass of plants. The shoot water content of E- plants was greater than E+ counterparts. A significant increase of Ni concentration of roots and shoots was also observed under Ni stress and the Ni concentration of E+ plants was 88.7% and 12.7% greater in shoots and roots, respectively, than in E- plants. Overall, results suggest that variation in response to Ni stress in E+ and E- ryegrass populations may aid survival of the grass under stress conditions.

Degradation of cell membranes is one of the consequences of cold stress. This study aimed to investigate the changes in the profile of fatty acids in the leaves of different clover genotypes under cold stress and select the most tolerant genotype. Experimental treatments included sampling time in two levels (autumn and spring), planting date in two levels, and 10 clover genotypes (7 cultivars of Persian clover and one cultivar of berseem, red and crimson clover). Lipid percentage was affected by season, planting date and cultivar. Persian clover (lately maturity) showed the highest lipid percentage with 3.5% and total unsaturated fatty acids percentage with 79% and the lowest ones were observed in crimson clover. Cold stress in autumn made a decrease of 20% in lipid percentage. It caused an increase of 21% in total saturated fatty acids, and a decrease of 5% and 20% in total unsaturated fatty acids and unsaturated fatty acids /saturated fatty acid ratio, respectively. Delay in planting date reduced the percentage of lipid in clover cultivars. In all cultivars, the percentage of unsaturated fatty acids was higher than saturated fatty acids. We can use the unsaturated fatty acid percentage as a criterion for selecting genotypes regarding cold tolerance. In this regard Persian clover (lately maturity) was the most tolerant genotype under cold stress conditions.

A study with complete randomized design block and three replications was carried out in greenhouse condition to examine the effects of inoculation of mycorrhiza fungi (Glomus intraradicea) and (Glomus mosseae) on growth indices, chlorophyll content, carotenoid, and protein of parsley (Petroselinum crispum L.), dill (Anethum graveolens L.), and celery (Apium graveolens L). The study was conducted in different experimental plantation environments (soil, sand and hydroponic). The highest colonization was seen in celery (100%) in sand culture and the lowest colonization was observed in parsley (33%) in hydroponic culture. There was no significant difference between the two fungi in terms of colonization and its effect on plant growth. Based on the effects of symbiosis of sand culture plants, some of the plants were selected randomly and transferred to hydroponic culture. The first week in the hydroponic culture was featured with a decreased colonization, which had no negative effect on the plant’s growth. The traits under consideration were significant at probability level of 5%. The results showed that the effect of colonization on plants’ growth was a function of growth culture and the host plant.