جستجوی مقالات مرتبط با کلیدواژه « تنظیم کننده های رشد » در نشریات گروه « کشاورزی »

It is important to research in the field of germplasm protection of native and medicinal tree species in northern Iran forests, especially blood hawthorn with many medicinal properties. Sexual reproduction of hawthorn is possible with apomixis due to the thick shell and two types of physical and physiological dormancy, and its asexual reproduction by rooting cuttings faces many problems. Bloody hawthorn (Crataegus atrosanguinea from the Rosaceae family) is considered one of the valuable species of the forests of the north and west of the country, which is very important due to its fruitfulness, very strong wood, and numerous medicinal properties. The medicinal properties of hawthorn have been proven in the treatment of blood pressure, arteriosclerosis, heart congestion, heart muscle weakness, and coronary insufficiency. Hawthorn contains many secondary metabolites such as flavonoids proanthocyanidin and glycosides. Optimizing the in vitro cultivation conditions of blood hawthorn as one of the natural species of Iran can be a suitable solution for its propagation. The present research was carried out to control pollution, control browning, and induce the callus of blood hawthorn (C. atrosanguinea) in vitro. Controlling the contamination of explants, seeds, and plant tissues is of great importance for the success of plant tissue culture. Since the enrichment of natural plant explants is a priority for tissue culture, this is usually associated with many problems with browning, especially for woody plants that have a thick and woody stem. Determining the type and concentration of the growth regulator of a variable factor is necessary for the growth of plants under in vitro conditions. After applying the growth regulator to the culture medium, the plant will show different reactions, but one of the appropriate ways to choose the correct path of plant regeneration is to determine the wet and dry weights of the callus, which is widely measured as a standard of callus growth. The callus growth curve can be obtained using the wet and dry weights of the callus. The results of past research indicate a wide range of changes in the type and concentration of growth regulators on callus formation and regeneration of different species of the hawthorn genus. A specific type and concentration of growth regulators should be applied according to the type of plant species.

Young and healthy stems of blood hawthorn were collected from Larijan in Amol, Mazandaran province, Iran, with geographical coordinates of 38' 58° N and 10' 52° E, at the beginning of the growing season. The collected stems were immediately transferred to the plant tissue culture laboratory of the Faculty of Natural Resources at Sari University of Agriculture and Natural Resources, Iran. Disinfection of natural hawthorn stems is very necessary due to surface and tissue contamination. For this purpose, explants of 0.5-1 cm size were cut from the stems. The infection control treatments included HgCl2, H2O2, NaClO, and AgNO3, and five treatments were designed to control the browning of explants. Browning control treatments included control, running water, ascorbic acid, polyvinyl chloride, and activated charcoal. In general, the culture medium consisted of substances including mineral salts (micro- and macroelements) as providers of maximum growth, amino acids and vitamins as nitrogen sources, sugar as a source of carbon and energy, growth regulators as growth and morphogenesis stimulants, agar as the solidifier of the cultivation medium, and water, which includes 90% of the cultivation medium. In this research, the culture medium was MS, which was first created by Driver and Koniaki (1984) and prepared according to Dufussard (1976). In this study, the pH of the culture medium was set to 5.8. For callus induction, IBA, NAA, 2,4-D, BAP, TDZ, and Kin treatments at three concentration levels of 0.1, 1, and 6 mg/L and a combination of NAA (6 mg-1) + BAP (1 mg-1), and IBA (6 mg l-1) + BAP (1 mg-1) were used in the MS culture medium. Stem explants were placed horizontally on the culture medium. Among different callus treatments, callus percentage, degree of callus, callus fresh and dry weights, and cross-sectional area of callus were measured to investigate callus induction. The best treatment was obtained by calculating the mentioned characteristics and that treatment was used for planting. It was transplanted approximately every 20 days and a total of 5-6 times. After callus cultivation in the reproduction medium, the explants were placed in a culture chamber and adaptation racks under 16 hours of light and 8 hours of dark treatment at 25 ± 2 °C with a humidity of 70%.

HgCl2 (0.5%, 16 minutes) with an average of 100% health was the most appropriate pollution control treatment. The control treatment with 98% health was observed as the most appropriate browning control treatment. Moreover, the type, concentration, and interaction effect of the type and concentration of the growth regulator significantly affected the callus induction characteristics of blood hawthorn (P < 0.01). The highest fresh and dry weights of callus, percentage and degree of callus formation, and cross-sectional area of callus were observed among auxin and cytokinin treatments, respectively, for 6 mg/L of NAA and 1 mg/L of BAP treatments. The highest levels of the studied callus induction characteristics were observed in the culture medium containing the combination of auxin and cytokinin (6 mg-1 of IBA+1 mg-1 of BAP).

In general, the results showed a 90% chance of controlling the browning of the explants of natural blood hawthorn branches in a normal state and without applying any treatment. It is recommended to use 0.5% mercuric chloride for 16 minutes to disinfect the explants. The combination of growth regulators in the culture medium was evaluated as very suitable for the callus induction of bloody hawthorn. The results of this research can provide laboratory instructions for the regeneration and mass reproduction of blood hawthorn.

Red seaweeds contain compounds such as agar and hormones that have many uses in industry. This research was done to determine biomass and extract two hormones and agar from Gracilaria corticata algae. Methods Sampling was done from December 2014 to November 2015 in Bushehr port, one month apart. Biomass and environmental parameters were measured and algae harvested in the selected transect. After the extraction steps, hormones are separated by the HPLC method and identified by standard injection. The highest amount of agar occurred in July with 63.3%, Zeatin in September with 21.9% and indole butyric acid with 19.21% in January. The highest fresh weight of this algae was measured in March at 423.33 grams per square meter. The results of the ANOVA and Chi-squared statistical tests showed a significant difference in 6 months of sampling in all samples (P<0.05). The amount of agar showed a significant correlation with the biomass. Also, among environmental factors, agar was correlated with salinity and temperature. Butyric indole of acid in January caused the growth of alga, but Zeatin did not show a significant effect on the growth of this species. In general, in order to extract these materials, harvesting can be done in the months that have the highest amount. Considering the exorbitant price of these hormones and the need to use them in algae extracts and algae liquid fertilizer, this research is a starting point for extracting all kinds of hormones from these algae.

Glycyrrhiza glabra L. is one of the valuable medicinal plants of the world, whose glycyrrhizin, the most important triterpenoid metabolite in its roots, is widely used in food and modern pharmaceutical industries. To overcome the seed germination problems, the risk of plant extinction due to the indiscriminate root harvesting, and the slow rate of natural biosynthesis of secondary metabolites, it is necessary to study on this plant root tissue culture and use elicitors to increase its glycyrrhizin biosynthesis. In the present study, the seed germination rate of two Iranian licorice ecotypes (Kashmar and Joghtai) and an Iraqi ecotype was investigated at different levels of sulfuric acid pretreatment. In addition, differences between the ecotypes in terms of morphology and root glycyrrhizin content were studied in response to IAA and NAA auxin elicitors with concentrations of 0, 0.5, 1, and 1.5 mg.l-1 in ½ MS medium using root explants. The results showed that all three ecotypes obtained the highest seed germination in the 98% sulfuric acid pretreatment for 40 minutes. The Iraqi ecotype was placed in the statistically best group in terms of all traits except glycyrrhizin content under control and some hormone levels (esp. NAA) conditions. In the Iranian ecotypes, the auxin elicitors application significantly improved the root traits and glycyrrhizin content. Kashmar ecotype produced the thickest roots using 0.5 mg.l-1 of IAA and the highest root dry weight (5.8 and 5.4 mg, respectively) using the medium and high concentrations of NAA and IAA. Joghtai ecotype also produced the heavy roots with 1.5 and 0.5 mg.l-1 of IAA and NAA (100 and 79 mg, respectively). In general, the medium and high concentrations of IAA and NAA (1 and 1.5 mg.l-1) caused the highest glycyrrhizin production (8.82 and 7.83 µg.g-1 DW, respectively) in Kashmar ecotype roots. Therefore, selection of appropriate ecotype and auxin elicitors application can increase in vitro production of biomass and root glycyrrhizin content in G. glabra.

In order to evaluate the effect of seed priming of Quinoa (Chenopodium quinoa Willd) on Seedling growth and germination Indexes of two varieties of Quinoa (Titicaca-Giza 1), studies in the form of a factorial experiment in a randomized complete block design (RCBD) with two factors four repetitions were conducted of Seed Technology Laboratory Shahed University in 2020. The experiment was the first factor included control ((no priming), Hydropriming, Potassium nitrate (0.02% w / v), Salicylic acid (0.6 mM), Calcium chloride (at 20 and 40 mM) and two genotypes of quinoa (TiticacaGiza 1). The best priming level for 40 mM calcium chloride was in both genotypes. Results of experiment showed that effect of priming on seed percentage at the level of one percent was significant but their interaction priming, genotyping on seed percentage not significant. Also, effect of priming, genotyping and their interaction on normal seedling percentage, seedling length, allometric coefficient and seed vigor length index, at the level of one percent was significant. Results showed that the highest seed percentage obtained in for level 20 (100 %) and 40 (100 %) mM calcium chloride priming in both genotypes (Titicaca-Giza 1). Generally, priming of 40 mM calcium chloride to highest germination indexes and of Titicaca and Giza1 genotype was recommended.

Hairy and adventitious roots are efficient systems for expressing recombinant proteins. In the present study, the amount of DrsB1-CBDAvr4 recombinant protein in hairy and adventitious root systems was compared. To this end, the effect of different factors on the optimization of culture conditions to obtain adventitious and hairy roots was evaluated in three separate experiments by assessment of biomass production in T1 transgenic plants expressing DrsB1-CBDAvr4 recombinant protein. The efficacy of Agrobacterium rhizogenesis in producing hairy roots was ensured using rolC gene specific primers. The insertion of DrsB1-CBDAvr4 recombinant peptide transgene in the genome of hairy and adventitious roots was confirmed by PCR analysis. Also, the level of DrsB1-CBDAvr4 protein was measured in hairy and adventitious roots by ELISA analysis. Analysis of the variance of data showed that the highest number of roots and the longest roots were obtained in MS media supplemented with 1 mg/L NAA and 0.5 mg/L IBA. The results of adventitious root biomass showed that liquid MS medium containing 1 mg/L of NAA hormone had a significant effect (P <0.01) on biomass production. More biomass was obtained in MS medium supplemented with 1mg/L NAA, whereas a lower fresh and dry weight was obtained in a 1/4 MS medium with no NAA. The results also showed that ATCC15834 strain with MS media supplemented with 3% sucrose, 10 minutes inoculation time was high efficiency to induce hairy roots in tobacco plants. The results of ELISA analysis showed that clones obtained from both roots showed a significant difference in terms of total protein content. The amount of recombinant protein from hairy roots was much higher than that of adventitious roots.

Persian rose or Varak (Rosa persica) is a thorny shrub belongs to Rosaceae family. This small scented plant due to the having a yellow-flower with a distinct reddish-brown spot in petals base and tremendous resistance to heat and drought has a great potential for modern rose breeding. Since there are not any available reports on germination habit of this aforementioned species, therefore the goal of this experiment is to evaluate the seed viability and type of dormancy in this anomalous species.

To increase the germination percentage of R. persica, collected seeds were exposed to 96% of sulfuric acid for 0, 10 and 30 min. whereupon sulfuric acid-exposed seeds were sown on MS (Murashige and Skoog) media supplemented with 0, 0.1, 1 and 10 mg/l gibberellic acid. This combination was evaluated under ex vitro (Petri dish) and in vitro (in MS media) condition at 4 and 24°C in incubator. Data collected from many traits related to the root and stem after 6 weeks of the experiments.

Despite confirmation of seed viability via Tetrazolium test, standard germination test was failed under ex vitro condition and a few weeks after the beginning of the experiment all specimens became infected with fungus. However, under in vitro condition, treatment of seeds with sulfuric acid for 10 min and then 1 mg/l gibberellic acid, were significantly effective on germination percentage and more than 60% germination frequency was observed in 10-minute sulfuric acid treatment in a hormone-free medium while no seeds have germinated in the control. The maximum root and stem length, hypocotyl length, epicotyl length, seedling length and the number of leaves has achieved when seeds exposed to sulfuric acid for 30 min. However, 10 min treatment of seeds with sulfuric acid was more effective in increasing the length and number of lateral roots and stem diameter. Root and stem length, hypocotyl length and seedling length has increased when gibberellic acid augmented. Stem diameter, length and number of lateral roots were higher in hormone free medium while the number of leaves and epicotyl was higher in medium supplemented with 0.1 mg/l gibberellic acid.

The effect of sulfuric acid on improving germination indicates physical dormancy of Iranian rose seeds. Application of whole treatments did not result to germination at 4°C. Seeds respond to germination treatments only at 24°C. The result of our study on temperature unlike other rose species reveals no need for stratification treatment.

Despite the economic importance of saffron, significant research has not been done in the field of molecular biology and genetics of this plant. Sterility and triploid genome, along with lack of genetic diversity are main reasons for this lack of research. Optimization of saffron cell suspension is a great step forward. It will provide the possibility of studying the production of saffron secondary metabolites, gene transformation, and mutagenesis cellular level. There have been few reports of cell suspension culture in saffron, mainly for the production of secondary metabolites (Yoon et al., 2015; Moradi et al., 2020; Taherkhani et al., 2019). In order to optimize the production of crocin and phenolic compounds, Moradi and co-workers produced calli from saffron stigma and then created a suspension culture from these calli (Moradi et al., 2020). However, the production of embryogenic cell suspension in saffron has not been reported. The aim of the current research was to achieve a cell suspension system with acceptable growth in saffron. For this purpose, different explants were subjected to different hormonal treatments to determine the optimal callus formation and suspension culture media.  Saffron corms were used to prepare explants. The lateral and terminal buds and the base of the corms were removed and the central part of the corms was used to prepare explants. Then, the explants were sterilized with 2.5% Sodium hypochlorite for 15 minutes. Explants were grown on CIM1 to CIM5 media (Table 1). After 5 weeks, the percentage of callus formation and the fresh and dry weight of calli were measured. The calli obtained from CIM2c treatment were used to prepare suspension culture with three different types of culture media (Table 1). To compare the speed of cell growth in different cell suspension treatments, the optical density (OD) measurement method was used. For all the assays, data were analyzed by one-way analysis of variance (ANOVA) followed by Tukey Honestly Significant Differences (HSD) Post-Hoc test using SPSS® statistical software, version 22 (IBM Corp., USA). The graphs were created using GraphPad Prism version 9 for Windows (GraphPad Software, California USA). The results showed that the concentration of 2 mgL-1 of 2,4-D and 1 mgL-1 of BAP had the best performance in callus formation and callus fresh weight. The calli of this treatment were used for cell suspension culture. SM3 medium had the best growth rate in cell suspension culture, but it did not have cells with appropriate shape and form. SM2 medium had a suitable growth rate and cells with small size and dry color, which had the best performance in terms of quality. In order to increase the quality, phenol production control materials were used. Adding PVP increased the growth rate of cell suspension in the SM2 medium. As we have shown, among the auxins 2, 4-D has a greater effect than NAA, contrary to other studies reported (Ahmad et al., 2013; Verma et al., 2016; Safarnejad et al., 2016; Georgiev et al., 2009; Sharma et al., 2008).  The current research showed the effect of treatment of 1 mgL-1 of BAP and 2 mgL-1 of 2,4-D on increasing the percentage of callus formation and the weight of calli taken from the saffron corms. SM2 and SM3 treatments had the best cell suspension growth rate. However, the SM3 treatment had cells with high starch vacuoles. Nevertheless, the SM2 treatment had smaller cells containing pigments.

In order to overcome the contamination problems, as well as the usual method of increasing potato through micro tuber, micropropagation has been considered through tissue culture. The aim of this study was to evaluate the callus induction and embryogenesis in potato cultivars using leaf explants.

For this purpose, micropropagation was performed using leaves from six different potato varieties in different mediums. Seedling of different cultivars in different concentrations of growth regulators, 2,4-D and TDZ showed that the highest amount of callus in 5 mgl-1 of TDZ growth regulator in the culture medium was observed in Batba, Fontane and  Sante. In 12 treatment combinations, the combination of 10 mgl-1 2,4-D and 10 mgl-1 TDZ was performed in leaf explants after three weeks of callus. Then, calluses were tested in a culture medium for embryogenic induction with four different treatments in suspension and solid culture.

In the experiment of embryogenesis study of leaf explants of different cultivars, results showed that explants was placed in a suspension culture of 0.1 mgl-1 Zeatin and 0.1 mgl-1 GA3 and 2.5 mgl-1 BAP and 5 mg/L GA3, and a solid culture medium containing 5 mgl-1 Zeatin and 2.5 mgl-1 BAP and 0.1 mgl-1 Zeatin and 0.1 mgl-1 GA3 had a much better embryogenesis. Among the 12 ‌ treatments applied, the highest callus formation rate was observed in ‌treatment ‌containing 10 mgl-12,4-D and 10 mgl-1 tidiazurone. ‌Results showed in suspension culture medium, 0.1 mgl-1 zeatin and 0.1 mgl-1 gibberellic acid treatment and 2.5 mgl-1 6-benzylaminopurine and 5 mgl-1 gibberellic acid had the highest embryogenesis, but in solid medium, treatment was 5 mgl-1 zeatin and 2.5 mgl-1 6- benzylaminopurine and treatment 0.1 mgl-1 zeatin and 0.1 mgl-1 gibberellic acid have better embryogenesis. Embryos produced in suspension culture medium were coated with calcium alginate and some of them were transferred to solid culture medium for regeneration.

The obtained results showed that it is possible to produce somatic embryos in large quantities in potatoes and these embryos can be used in the production of artificial potato seeds.

A pot experiment in soilless culture was performed as a factorial experiment based on the randomized block complete design with four replications in the research greenhouse of Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. The effect of foliar application of methyl jasmonate (MeJA) [distilled water (control), ethanol 1% (as solvent of MeJA and control), 1 and 2 mM MeJA] and Zn application (0, 0.025, 0.05 and 0.1 mgL-1) in Hoagland nutrient solution on the growth characteristics, photosynthetic pigments, and essential oil production of Mentha piperita L. was evaluated. According to the results, the highest growth was observed in 0.025 mg L-1 Zn and foliar application of 1 and 2 mM MeJA. The highest photosynthetic pigments of chlorophyll a and total chlorophyll were obtained in 0.025 mg L-1 Zn and foliar application of 2 mM MeJA. The highest root fresh and dry weights, chlorophyll b and carotenoid were observed in 0.05 mg L-1 Zn and foliar application of 2 mM MeJA and the treatment without Zn and foliar application with distilled water. In addition, the highest amount of essential oil production was observed in 0.1 mg L-1 Zn and foliar application with 1 mM MeJA. In general, 0.025 mg L-1 Zn and foliar application of 2 mM MeJA was the best treatment and improved most studied traits. The results of this experiment showed that Zn in low concentrations stimulate the peppermint growth; whereas Zn omission or application of high concentrations created some stressful effects in this plant increasing its essential oil production. Therefore, application of proper concentrations of Zn and MeJA can be a suitable way to improve the growth and essential oil production of peppermint.

To investigate the effect of triacontanol on the yield and yield components of the two chickpea Landraces, a completely randomized factorial design was conducted with three replications. The treatments were designed at four levels of hormone consumption including 0, 5, 10 and 15 mg/L in the form of leaf and soil applications on two chickpea Landrace of Mashhad and Kermanshah. The total treatments included 24 pots for each Landrace. In this experiment, traits such as grain yield, biological yield, number of pods per plant, number of grains per pod, height of plant, 100-grain weight, and total biomass of chickpeas were examined. The results revealed that the effects of triacontanol application and method of application on chickpea Landraces were not significant. The results also showed no significant effect for biomass. Moreover, analyzing the effects of interaction between the amount of hormone consumption and method of consumption and type of chickpea mass on the yield and yield components showed that all properties were significantly different with an exception of the number of grains per pod and 100-grain weight. Increasing the doses of hormone by leaf application on Mashhad Landrace resulted in significant improvement of yield and yield components of the chickpea. The triple interaction effects of triacontanol application, method of application and chickpea Landrace on the measured traits were significant in all treatments. In the triple interaction, the highest yield was observed in 15 mg/L triacontanol application on the leaves of Mashhad Landrace chickpea, which increased the yield by 45% compared to control treatment. It was concluded that the increase of yield and yield components by increasing doses of triacontanol application on leaves was mainly due to their effects on aerial parts of the plant through decreased rates of flowers, pods and falling leaves. On the whole, application of biochemical triacontanol hormone resulted in increasing chickpea yield by its positive effect on the metabolism activities of the plant.

Considering the importance of water in agriculture as well as extending ​​autumn-sown sugar beet cultivation area, this study was conducted to evaluate the effect of growth restriction treatments, planting date and cultivar on bolting and other quantitative and qualitative traits of autumn-sown sugar beet in Karaj, Iran during two years (2018-19). The experiment was performed as a factorial split plot in a randomized complete block design with 3 replications. Studied factors included two planting date (22nd September and 22nd October) as the first factor, the growth restriction with four levels including control (without limit), paclobutrazol (300 pp M), Nitrogen fertilizer restriction (50% of the recommended amount), Paclobutrazole + Nitrogen fertilizer restriction as the second factor, and three cultivars including Giada, Eudoro, and one Iranian genotype resistant to bolting as the third factor. Planting date and growth restriction factors were included in main plots and genotype factor in subplots. The studied traits included bolting percentage, root yield, sugar content, molasses sugar, and white sugar yield. Results showed that the effect of the year on bolting percentage was significant. The lowest bolting percentage (50%) was obtained by Eudoro cultivar on the second year of study planted on 22nd October. The highest root yield (79.91 tha-1) was related to the Eudoro cultivar, planted on 22nd September and treated with paclobutrazol (300 ppm). Giada and Eudoro cultivars planted on the 22nd September had the highest white sugar yield of 8.15 and 8.62 t ha-1, respectively with no significant difference between.

Protecting the germplasm of native tree species of the Caspian hyrcanian forests, especially the Caspian locust (Gleditschia capsica Desf.) is a priority of the research. In this study, somaclonal diversity in regenerated plants from different explants of Caspian locust was investigated using the Inter Simple Sequence Repeat (ISSR) marker under in vitro conditions. Mother leaf (natural) and stem, root and cotyledon explants from the regenerated plants as studied genotypes were selected and they were cultured in MS culture medium containing 0.5 mgL-1 TDZ and 0.5 mgl1 2,4-D. Somaclonal diversity was examined after six subculture inoculations. Polymorphism (PIC), Nei and Shannon diversity traits were used to investigate the diversity between genotypes and then clustering of genotypes was performed using UPMGA algorithm and Principal Component Analysis (PCA). The polymorphism percentage was 87.9% using 10 primers. Molecular Analysis of Variance (AMOVA) showed 16% diversity between genotypes and maternal origin. The results of cluster analysis grouped the genotypes into three distinct categories, which was also confirmed by principal component analysis (PCA). Accordingly, the mother basal and stem genotypes were grouped in a group. The mother basal had the highest and lowest similarity coefficients with stem and root genotypes, respectively. Therefore, it was suggested to use stem explants that have high genetic similarity with the mother genome for studies of Caspian locust tissue culture. In general, the results showed that somaclonal diversity among regenerated plants will increase with increasing number of subcultured.

It is essential to use corrective techniques in the cultivation of medicinal plants and to improve the quantity and quality of the essential oils and essence in them for the production of high-yielding plants. The influence factors in callus production and regeneration include genotype, growth regulators, culture medium, age and type of explants and environmental conditions. In this study, callus induction in seven plant species (Daucus carota, Dracocephalum kotschyi, Hyssopus officinalis, Galega officinalis, Amsonia tubemaemontana, Moringa oliefera, Urtica dioica) has been investigated in vitro, which were evaluated callus induction and organogenesis on the leafy specimen in MS and WPM medium with different concentrations of growth regulators. For this purpose, a factorial experiment was designed in a completely randomized design (CRD) and was investigated genotypic effects on callus induction and subsequent proliferation of the plant. The results showed that Daucus carota, Moringa oliefera and Hyssopus officinalis had a significant difference in callus induction with other species.

Avondol (Smyrnium cordifolium) is one of the most valuable medicinal plants and its use has a long history in the world. The aim of this study was to investigate the effect of growth regulators on the regeneration of various organs of the avondol in in vitro conditions. This study was conducted in tissue culture laboratory of Research Center of Agricultural and Natural Resources of Kermanshah as a factorial experiment in a completely randomized design with 3 replications. Factors of explant (leaf and stem) plant growth regulators of 2,4-D (0, 0.25, 0.5, 1, 2 and 4 mg/l) and BA (0, 0.25, 0.5 and 1, mg/l) were examined. Six weeks after planting, callus color, callus formation rate, percentage of callus regeneration, callus diameter and callus fresh weight were recorded. The results showed that the highest callus formation rate in 2 mg/l 2,4-D alone, the highest percentage of callus formation of explants in 1 and 2 mg/l 2,4-D alone was obtained in stem explants. The highest callus diameter in the treatment of 2 mg/l 2,4-D alone and the highest weight in 1 and 2 mg/l 2,4-D alone and 2 mg/l 2,4-D with 0.25 mg/l BAwas obtained.In order to direct regeneration, same calli were cultured on growth regulators BA (0.25, 0.5 and 1 mg/l) and IBA (0, 0.25, 0.5 mg/l) in MS medium with 3 replications. Six weeks after replanting the calli grew and did not regenerate. The results of the second experiment showed that the highest callus formation rate and callus diameter were obtained in combination of 0.5 mg/l BA alone. The highest percentage of callus formation was observed in two hormonal compounds: 0.5 mg/l BA alone and 1 mg/l BA with 0.25 mg/l IBA. The highest callus weight was obtained in 1 mg/l BA alone.

Saffron is a sterile triploid plant which is propagated by a daughter corms from the mother corm, thus improving its agronomic characteristics has been limited using conventional plant breeding. Tissue culture technology is a useful tool to improve crop characteristics. The purpose of this research is to find the appropriate protocol for the induction of callus in parts of saffron corms. A factorial experiment was carried out with plant growth regulators 2,4-D and BAP, at three levels (1, 2 and 3 mg/L) each, with 5 replications in a completely randomized design. The control samples had no any kind of growth regulator. These results indicate that MS culture medium supplemented with 2 mg/L 2,4-D and 2 mg/L BAP was the best culture medium for callus growth and formation. The purpose of this study was to achieve a suitable protocol for inducing embryogenic callus and indirect regeneration in saffron. To achieve this, an experiment was conducted in a completely randomized design with four replications using two growth regulators of 2,4-D, 0.5 mg/L, and BAP at three levels of 3, 4 and 5 mg/L. Observations showed that there were no significant differences between treatments. Then, these calluses were sub-cultured into two different levels of MS medium (half-strength MS and complete MS) without ABA with 3% and 6% sucrose, and with 1 mg/L ABA. The factorial experiment was conducted in a completely randomized design with 6 replications to examine embryo development. The results showed that the best medium for embryo development was complete MS medium containing 1 mg/L ABA. Finally, in order to growth and differentiation, these calluses were transferred to a MS medium with 6% sucrose. The observations indicated that calluses in full MS medium containing 1 mg/L ABA, showed the best reaction to regeneration.

Brassinosteroids promote plant growth by enhancing some metabolic activities such as photosynthesis, nucleic acid biosynthesis, proteins and carbohydrates. Mechanisms of resistance and tolerance in plants have been developed to tolerate water deficit stress. One way to deal with drought is to use plant growth regulators. Brassinosteroids were first extracted from the pollen of turnip (Brassica napus) and were considered as the sixth group of plant growth regulators. These compounds stimulate growth and cell division and affect electrical properties, membrane permeability, stability and activity of membrane enzymes. Nowadays, brassinosteroids have been extracted from various plants and their structure and function have been identified.

This experiment was conducted in a factorial experiment based on a completely randomized design on Capsicum annuum L. Castello cultivar under the average daily temperature of 25 °C and 18 °C at 75% relative humidity in greenhouses. Research conducted by the College of Agriculture, Isfahan University of Technology, with four drought treatments using polyethylene glycol 6000 solutions at four levels of 0, -6, -7, and -8 bar. Brassinosteroids were sprayed in two 1 μM control levels. Pepper seeds planted in transplanting trays containing 1 to 2 volumes perlite and vermiculite substrate. When the actual leaf of seedlings appeared, the root thoroughly rinsed with distilled water and then were transferred to black plastic containers with a diameter of 16 and height 13cm and 1L volume containing Johnson's nutrient solution including four dry treatments using 6000 polyethylene glycol solution and aerated in control for 15 minutes every 5 minutes. At the end of the experiment, vegetative factors such as fresh and dry weight of different parts of the plant, plant length, and volume, and physiological factors such as proline and abscisic acid content and chlorophyll fluorescence changes were measured.

The results of the analysis of variance table showed that brassinosteroid had no significant effect on most vegetative traits except root volume and weight and all physiological traits except chlorophyll fluorescence and the mentioned traits increased with the application of 1 mM brassinosteroid. However, the main effects of drought except for amino acid and the interaction of drought and brassinosteroids were significant on all traits. The results of the main drought effects showed that the root fresh weight at -8 bar and dry weight at -7 bar significantly decreased, whereas fresh and dry weight of the shoots at lower than -6 bar. The onset of decline showed that the root length and volume appeared to decrease with the onset of stress by -6 bar and the plant length also reduced with the first stress level. Drought stress at -6 bar level decreased chlorophyll fluorescence, chlorophyll index and Abscisic acid while at -7 bar decreased protein and increased proline. The results also showed that the amount of sulfuric, essential and unnecessary amino acids were significantly reduced by drought stress and brassinosteroid had no effect. Total amino acid content decreased with drought stress but there was no significant difference with control. With increasing drought stress, the fresh and dry weights of shoots decreased and the intensity of shoots decreased. The intensity of shoot growth decreased with the use of brassinosteroids at moderate stress but the mentioned trait showed the same adverse effects at all levels of stress. Brasinosteroid application decreased stress indices such as proline (7%) and abscisic acid (50%) and this decrease was more pronounced in proline, especially in more severe treatments. Amino acid and protein levels decreased with drought stress, and the use of brassinosteroids could not be effectively affected by this reduction, especially for the compounds and the amount of amino acids. The results of biplot analysis showed that the vegetative and protein traits had better mean in stress condition in the presence and absence of stress and in higher stress severity and application of brassinosteroid affected root fresh weight and abscisic acid content more than the other traits. While in mild stress it seemed to be more effectively on the steroid and most of the vegetative and physiological traits than the control.

It seems that the application of brassinosteroids on pepper seedling in drought stress at a concentration of 1 μM is effective in maintaining vegetative properties and reducing negative effects of stress and reducing stress indices.

In order to investigate the effect of supplemental irrigations (at flowering, podding, flowering + podding and rainfed as check) and exogenous application of different growth hormones (3 indoleacetic acid [IAA], gibberellic acid [GA3], 6 benzylaminopurine [6 BAP] and distilled water as check), an experiment was conducted at Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran. The results showed that the interaction of supplemental irrigation and hormone was significant on green pod yield, biological yield, 100-grains weight, harvest index. The number of pods per plant and grains per pod were influenced by the effects of supplemental irrigation and hormones. The use of supplemental irrigation at two stages (flowering and podding) and the application of hormones (IAA and 6-BAP) led to produce the highest grain yield, biological yield and 100-grains weight. Exogenous application of 6-BAP increased the Fv/Fm (photochemical efficiency of photosystem II), performance index, soluble sugar, soluble protein and leaf relative water content. In general, the supplemental irrigation and exogenous application of growth hormones particularly IAA and 6-BAP, can be suitable to prevent exposure of pea to drought stress during critical stages of flowering and podding and thus increases its economic performance.

Fritillaria imperialis from the Liliaceae family is an ornamental species in danger of extinction. Therefore, it is nessessary to conserve the plant genetic pool. Two proper methods to access this goal are micropropagation and germplasm conservation in in vitro freezing conditions. The presence of suitable pre-treatments is necessary for cryopreservation. The most important and the most application of pre-treatment is encapsulation-dehydration. The purpose of current research was in vitro proliferation of F. imperialis using plant growth regulators and its cryopreservation using encapsulation-dehydration pre-treatment. 

Bulb scales as explants and MS medium as basic culture medium were used. For micropropagation, kinetin (Kin) and α_naphthaleneacetic acid in concentrations of 0 (as control), 0.5, 1 and 2 mg l–1 were applied. For cryopreservation, explants were pretreated with encapsulation-dehydration followed by conservation in liquid nitrogen. Encapsulation was done using sodium alginate. Dehydration was carried out in air and using high level of sucrose.

The results of micropropagation showed that the maximum number of leaf (3.5) and root number (5.7) was obtained in explants treated with 0.5 mg l–1 Kin along with 1 mg l–1 NAA. The results of cryopreservation showed that encapsulation-dehydration in air as a pre-treatment had effective role on the survival and regeneration of explants (70.5%) after conservation in liquid nitrogen. Least explant survival was obtained in control (without pre-treatment). In vitro regenerated plantlets were cultivated in plastic pots containing peat moss and perlite (in ration of 1:1) and acclimatized with environmental conditions. The survival rate was 90% and the growth pattern of regenerated plants was similar to that of mother plants.

Present research proposes the use of 0.5 mg l–1 Kin together with 1 mg l–1 NAA for micropropagation and encapsulation-dehydration for germplam cryopreservation of F. imperialis. Micropropagation by direct and indirect organogenesis and embryogenesis is a proper approach for proliferation of ornamentals in danger of extiction. The success of these methods depends on type and concentrations of auxins and cytokinins applied in culture medium, singular or in combination. In order to protect rare and endangered ornamental species, modern biotechnological tools need to be utilized.

Rosmarinic acid (RA) is a well known valuable phenolic compound because of its wide spectrum of biological activities such as antimicrobial, anti-inflammatory, antimutagenic, antioxidant and cancer chemoprevention. In the present study, in vitro callus induction and production of RA in Salvia nemorosa (callus culture, in vitro seedling, mother plant) have been studied. For this purpose, callus induction was achieved from young leaf explants cultured on MS medium supplemented with different concentrations of 2,4-D (0, 0.5, 1, 2 and 5 mgL-1) solely or in combination with BAP and Kin (0.5, 1 and 2 mgL-1) and the number of different traits such as percentage of callus induction, fresh weight and type of callus (texture and color) were evaluated. The highest percentage of callus induction was achieved from 3 treatment supplemented by 5 mgL-1 2,4-D+ 2 mgL-1 BAP, 1 mgL-1 2,4-D + 1 mgL-1 BAP and 2 mgL-1 2,4-D + 2 mgL-1 Kin. Also The best fresh weight (1.31g) were obtained in MS medium containing 1 mgL-1 BAP and 1 mgL-1 2,4-D. According to the result the callus has the highest RA content with a value of 1.5 mg gdw-1 and RA accumulate in callus to amounts (2 fold) much higher than plants under field conditions. According our findings the callus culture of Salvia nemorosa L. on MS medium containing 1 mgL-1 BAP and 1 mgL-1 2,4-D provided useful method for RA production.