growth regulator

The usual method of Haworthia attenuatae propagation hasn’t commercial returns due to the low number of offsets and rooting of leaf cuttings. In the present study, micro-propagation of this plant was evaluated using leaf explants and BAP, and KIN (0.5, 1 and 2 mg / l) in combination with NAA (0, 0.01, 0.1 and 0.5 mg/l). The results showed that the maximum number of shoots was regenerated using BAP in combination with NAA from the basal leaf segment explant. The maximum number of leaves (3.55) and the longest leaves (0.61 cm) were obtained on medium containing 2 mg/l BAP and 0.01 mg/l NAA using the basal leaf segment explant and the widest Leaves (0.44 to 0.48 cm) was observed on the medium containing 2 mg/l BAP without or with low concentration of NAA. The results of KIN application showed that the longest leaves (0.56 cm) with the maximum numbers (2.45) were obtained on medium containing 2 mg/l KIN and 0.01 mg/l NAA from the entire leaf explant. More over, the widest leaves (0.87 cm) was produced on medium supplemented with 2 mg/l KIN. The findings of rooting on MS and½ MS media supplemented with 0, 0.5, 1, 1.5 mg/l NAA showed that the highest number (4.33) and the longest roots (2.16 cm) were produced on ½MS medium containing 0.5 mg/l NAA. 90% of rooted plantlets were adapted to the greenhouse environment. Totally, the accurate optimization of this protocol can be applied to commercial micro-propagation of H. Attenuatae from leaf explants.

Drought stress as a non-biological stress in nature has several dimensions and affects plants at different levels. During prolonged drought stress, the amount of water in the plant cells decreases and causes thorogenesis, which eventually leads to plant death. The concentration of solutions in the cytosol and extracellular matrices increases due to drought stress in plants and cell development decreases as a result, which leads to growth inhibition and failure to reproduce. Subsequently, the plant withers with the accumulation of abscisic acid and compatible osmolytes such as proline. Overproduction of reactive oxygen species and formation of scavenging compounds of radicals such as ascorbate and glutathione take place at this stage. Drought stress also affects stomatal closure, physiological traits, gas exchange, reduced transpiration, and reduced carbon assimilation (photosynthesis). Drought stress also affects stomatal closure, physiological traits, gas exchange, transpiration reduction, and carbon assimilation reduction (photosynthesis). Negative effects on mineral metabolism and nutrition (absorption and transport of nutrients) reduce leaf area and change the distribution of assimilates between organs.
Organic matter is essential for fertility and preservation of soil biological, chemical and physical properties. Recently, much attention has been paid to the possibility of using organic matter to improve plant growth. Humic substances (humic acid and folic acid) are among the organic substances that are used as growth regulators under suitable irrigation conditions and drought.
In recent years, the number of studies on melatonin in plants has increased significantly. The wide range of functions in different organisms indicates the potential of this substance in plant physiology. Its role as an anti-stress agent against stressors such as water, salinity, low temperature and high temperature, UV and toxic chemicals has been analyzed. The antioxidant role and growth promoter (among other melatonin functions in the plant) is very important. Melatonin is a polar molecule with diverse physiological and cellular functions. Melatonin has received a great deal of attention in recent years, as research has shown that melatonin is widely found in the leaves, roots, stems, fruits, and seeds of all plant species.
To date, numerous applications of fulvic acid and melatonin in agriculture, food industry and animal sciences have been proposed, but unfortunately few studies have been conducted on the simultaneous use of fulvic acid and melatonin in agriculture, which necessitates research in this area. Therefore, considering the economic importance and increasing demand for small fruits, especially strawberries, in this study, the effect of fulvic acid and melatonin on the biochemical properties of strawberries under water stress was investigated.

This experiment was performed in Bostanabad city (East Azerbaijan province) in Iran. Strawberry seedlings (Kamarosa cultivar) were obtained from a commercial strawberry growing greenhouse in Urmia in October and transferred to the greenhouse in cultivation trays. Laboratory studies were performed in the laboratories of the Department of Horticulture and Soil Science, Faculty of Agriculture, Mohaghegh Ardabili University. This experiment was performed as a factorial experiment in a completely randomized design with 3 factors in 4 replications. Factors include water stress at three levels of 100 (full irrigation (control), 25 and 50%, maintainable water drain), fulvic acid at three levels (control, 200 and 400 mg/l) and melatonin at three levels (control, 75 and 150 μM). After complete establishment and cooling of plants, melatonin and fulvic acid were applied to the treatments in three stages through foliar application. The first stage was performed after complete establishment of the plant (15 days after planting), the second stage was performed 10 days after the initial time of treatment and the third stage was performed 10 days after the second stage of foliar application. It should be noted that distilled water was used to treat the plants in the control group.
In order to apply water stress to the plants, at first the soil is completely dried (to decrease the effect of moisture on the weight of the soil in the pot), then the same amount of coarse sand was poured on the floor after weighing to create sufficient drainage in the pots. The pots were then placed on a scale (accurate to one tenth of a gram) and the soil mixture was poured into all of them. Then one of the pots was selected randomly and the soil inside it was completely submerged and covered with plastic and allowed the gravity water to come out. Because this part of the soil moisture is useless for the plant and must be drained. The pot was weighed and taken daily for a week (until the weight of the pot was fixed) after the soil moisture reached the field capacity. Then the soil inside the pot was emptied in a special container and the mass of the container along with the soil inside it was recorded and dried in an oven at 105 ° C for 24 hours. After removing from the oven, the soil with the container was weighed again and the difference between these two masses (before the oven and after the oven) showed the mass of water (Mw) of the soil in the pot in the last stage of the experiment. The mass of the container was deducted from the mass of the soil sample along with the container after the oven and the mass of dry soil (Ms) was calculated. Finally, the mass moisture content (θm) was obtained using the following equation.
Measurement and amount of Mw according to the relationship between humidity (mass moisture (θm)) at that stage, was obtained after obtaining moisture in the last stage of the experiment and adding the mass difference of the pots in each time period. (Given that the difference in the mass of the pots on each successive day indicates the amount of water evaporated and the amount of dry soil at each stage is constant). By obtaining the mass of the pot and the mass moisture, a linear relationship between them was drawn by Excel software. The moisture content of the pots was calculated by the regression relationship with the mass of the pots at the stress levels.

Analysis of variance of data showed that the effect of drought stress and its interactions with fulvic acid and melatonin treatment on yield, RWC, electrolyte leakage and antioxidant enzymes activity were statistically significant. The interactions between treatments (drought stress, fulvic acid and melatonin) were statistically significant and only the triple effects of catalase were not statistically significant. The results showed that the drought satress (25 and 50%, maintainable water drain) without the application of fulvic acid and melatonin ecreased yield, RWC and increased electrolyte leakage. But application of fulvic acid and melatonin increased the yield and RWC under drought stress conditions. Furthermore, the application of fulvic acid and melatonin reduced the oxidative damage (electrolyte leakage) in the plants through increased enzymatic activity under drought stress conditions. Generally, the highest and lowest yield was obtained in control plants (full irrigation) with foliar spraying with melatonin (150 µM) and 50%, maintainable water drain which were 693.54 and 504.78 g, respectively. The highest and lowest ascorbate peroxidase activity was obtained in 50%, maintainable water drain with foliar spraying melatonin (75 µM) and control plants (full irrigation) with foliar spraying melatonin (75 µM) and fulvic acid (400 mg/l) which were 2.929 and 1.426 µmol min-1 gFW-1, respectively. The highest and lowest peroxidase activity was obtained in 50%, maintainable water drain with foliar spraying melatonin (75 µM) and fulvic acid (200 mg/l) and control plants (full irrigation) with foliar spraying fulvic acid (400 mg/l) which were 2.411 and 0.58 µmol min-1 gFW-1, respectively. The highest and lowest superoxide dismutase activity was obtained in 50%, maintainable water drain with foliar spraying melatonin (150 µM) and fulvic acid (400 mg/l) and control plants (full irrigation) with foliar spraying fulvic acid (200 mg/l) which were 96.93 and 36.18 µmol min-1 gFW-1, respectively. The highest and lowest level electrolyt leakage leaves also were observed in 50%, maintainable water and control plants (full irrigation) with foliar spraying melatonin (150 µM) and fulvic acid (200 mg/l) which were 96.93 and 36.18 respectively. The highest and lowest relative water content (RWC) were obtained control plants (full irrigation) with foliar spraying with melatonin (150 µM) and 50%, maintainable water drain which were 95.35 and 53.92%, respectively. The highest and lowest catalase activity was obtained in 50%, maintainable water drain with foliar spraying fulvic acid (400 mg/l) and control plants (full irrigation) which were 0.7108 and 0.4946 µmol min-1 gFW-1, respectively.

Overall, the results of the present study suggest that the use of melatonin and fulvic acid may be an effective approach to improve the yield of strawberry plants under drought stress. Melatonin and fulvic acid helped to strengthen the antioxidant enzymes system of strawberry plants, which reduced the oxidative damage. Also, foliar application of melatonin and fulvic acid had a protective role on strawberry plants grown under drought stress and its optimal concentration will be useful in increasing drought tolerance in many crops.

Drought is one of the most important factors in reducing plant yield, and understand the ways to deal with drought stress is very important. This experiment was performed to study the effect of foliar application of organic growth stimulants (Hamoon Green ®) on some physiological traits, yield, and oil content of Goldasht safflower cultivar under different levels of drought stress in the form of split plots in a randomized complete block design in the Research Farm No.1 of Zabol University located in Jazinak, Sistan Dam, in Zabol with three replications. The main factor of drought stress at 3 levels included full irrigation, irrigation up to the main stem flowering stage, and irrigation up to full flowering stage. The secondary factor was plant growth regulator at four levels including control, 8, 10, and 12 liters per hectare. Measured characteristics included plant height, number of leaves, number of heads per plant, 1000-seed weight, petal weight, stem diameter, seed protein percentage, grain yield, seed oil percentage, proline, catalase and peroxidase. The interaction of growth stimulant levels and drought stress was significant only on plant height, stem diameter, oil percentage, and proline concentration. The maximum plant height (64 cm) and percentage of oil (32.7%) were obtained from non-stress and foliar application of 12 liters of growth stimulant; the highest proline concentration was recorded under foliar application of 12 liters growth regulator the flowering stage of the main stem (0.38%); the maximum stem grain yield (1127.08 kg ha-1) was recorded with the plants sprayed with 12 liters of growth stimulant. In general, foliar application of growth stimulants moderated the negative effects of drought stress on some traits of safflower plant and improved grain yield by 36.6%. Also, irrigation up to the flowering stage of the main stem can lead to the yield similar to full irrigation.

The study of plant death is completed by defining plant cell senescence. Senescence is an inseparable part of plant growth. Like many other plant processes, this is a genetic control program that is regulated by a set of environmental and genetic factors. These factors and their mechanisms respond to the relationship between sources and sinks in which glucose signals and hormonal regulation and cellular genetics play a major role. During senescence, nutrients such as nitrogen, phosphorus, and glucose are released from the breakdown of macromolecules in leaf cells, to be assigned to growing organs or storage tissues. Symptoms of leaf senescence include chlorophyll loss, dehydration, and eventually plant death. Recognition of senescence is very necessary because with sufficient knowledge, senescence can be manipulated in the desired direction. For example, current molecular genetic approaches are used for postpone senescence, like blocking ethylene production or increasing cytokinin production. They are based on plant hormone mechanisms. Plant storage products increase their life span. In order to understand leaf senescence, many genetic SAGs, especially transcription factors and encoding components of transmission pathways, various gene functional methods are described.

Cumin (Cumin cyminum L.) the only cumin crop in Iran, which is rich in secondary metabolites has great economic value and is. In order to evaluate the effect of foliar application of growth stimulant of pluramin and bioxa on this plant, a field study was conducted as a factorial experiment in a randomized complete block design with four replications in the research farm of Shahid Madani University of Azerbaijan in 2017- 2018. Experimental factors included foliar application of pluramin at the concentrations of 0, 2.5 and 5 g.l-1 and bioxa at the levels of 0, 5 and 10 ml.l-1. The essential oil was extracted using hydro-distillation method in Clevenger apparatus and analyzed by GC/MS. The effect of foliar application of pluramin on 1000-seed weight, number of seeds per umbel and essential oil yield and the effect of foliar application of bioxa on plant height, number of seeds per umbel and content and yield of essential oil were significant. The interaction of experimental factors on the number of seeds per umbel, content and yield of essential oil was significant. Comparison of means showed that the highest content and yield of essential oil with a significant difference belonged to the foliar application of 10 ml.l-1 bioxa; after that, spraying 2.5 g.l-1 of pluramin produced the highest content of essential oil. The major compounds identified in all treatments included 3-carn-10-al, para-cement, p-comic aldehyde, gamma-terpinene, beta-pinene and 2-carn-10-al. The highest essential oil yield was obtained from foliar application of 10 ml.l-1 bioxa, which was significantly different from the other levels of foliar application. That is, simultaneous foliar application increased this compound. The highest amount of para-cymene, gamma-terpinene and beta-pinene was obtained by spraying 10 ml.l-1 bioxa and the lowest amount of these compounds were obtained by spraying 5 g.l-1 pluramin and 5 ml.l-1 bioxa. Overall, the results showed that foliar application of growth stimulants of pluramin and bioxa can improve the yield and composition of cumin essential oil under the rainfed conditions.

Medicinal plants are the most exclusive source of life saving drugs for majority of the world’s population. Plant tissue cultures can be established routinely under sterile conditions from explants, such as plant leaves, stems, roots, etc. Both for multiplication and extraction of secondary metabolites. Solanaceous plants, such as genus Hyoscyamus, are regarded as rich sources of tropane alkaloids. Present study, H.arachnoideus Pojark, were investigated. Three types of explants (leaf, root) derived from seedlings, were cultured on Murashige and Skoog’s medium supplemented with 3% sucrose, 0.75% (w/v) agar. We investigated the effect of different concentrations of Ca2+, NO-3 on Murashige and Skoog’s medium supplemented with 3% sucrose and 0.75% (w/v) agar in two explant types (leaf and root) of H.arachnoideus with four concentration levels of auxin naphthalene acetic acid(0, 0.5, 1, 2 mg/l), in compare with Murashige and Skoog’s medium supplemented with 3% sucrose, 0.75% (w/v) agar as control, In order to determine callus biomass and total alkaloid content. Our findings showed that, increased concentrations of Ca2+ was found to have positive effect on callus biomass and total alkaloid content. NO-3 had different effects on callus biomass and alkaloid production, but increased concentrations of NO-3 could enhance callus biomass and decrease alkaloid content, in some cases.

The mass propagation and breeding new varieties of Ziziphus jujuba Mill as a valuable fruit tree and herb, which is well adapted to dry and semi-arid climate, is very important. The aim of the present research was to optimize direct regeneration method in Ziziphus jujuba Mill. In this experimental study, the explants consisted of leaf cut into 3 parts, leaf cut from 4 sides, and full leaf of in vitro and compared in Murashige and Skoog and woody plant media with different concentrations of Thidiazuron (TDZ; 0, 5, 10, 15, and 20μM) and Naphthalene acetic acid (NAA, 0 and 1μM). The effect of 2 and 4 weeks of darkness on regeneration rate was investigated. The experiments were conducted in factorial based on a completely randomized design. The mean of statistical data was compared using Duncan’s multiple range test. SAS 9.3.1 software was used and the difference was considered significant at 1% probability level. Findings: The 2 weeks of darkness treatment with the mean of 1.38 was better than the 4 weeks of darkness treatment. The Maximum number of shoots (2.27) was obtained in leaf cut into 3 parts. The maximum percent of regeneration (75.0%) and highest number of regenerated shoots (4.83) were obtained in the MS medium containing 10μΜ TDZ and 1μΜ NAA. Regeneration rates in Ziziphus jujuba Mill is affected by the type of explant, culture media and plant growth regulators. Maximum rate of regeneration is observed in leaf cut into 3 parts and cultured on MS medium containing 1μM NAA and 10μΜ TDZ. Plantlets are rooted and successfully acclimatized at “in vivo” conditions.

This study was performed in order to evaluate the effect of methyl jasmonate on some physiological characteristics and antioxidant activity of basil under lead toxicity, based on a factorial and completely randomized design with three replications at Ferdowsi University of Mashhad Research Greenhouse. The experimental treatments included Pb (NO3)2) at three levels of (0, 200, and 400 mg/kg soil) and foliar application of methyl jasmonate at three concentrations (0, 0.5, and 1 mM). Measured traits included chlorophyll a, b, and total, carotenoids, electrolyte leakage, relative water content, antioxidant activity, soluble carbohydrate, total phenol, and proline. Results showed that in the plants treated with lead, the amount of proline, relative water content, chlorophyll a, antioxidant activity and total phenol reduced in comparison with control plants and application of methyl jasmonate (0.5 mM) under lead stress increased these traits. Furthermore, electrolyte leakage increased significantly under lead stress, while it was decreased by spraying with methyl jasmonate. Therefore, using methyl jasmonate is justified for protecting economic performance of plants under stress. Also, application of 0.5 and 1 mM methyl jasmonate reduced and adjusted the effects of stress in the plants under lead stress through stimulating production of antioxidants.

Salicylic acid is one of growth regulator that has important role in regulation physiologic process in plants. Current investigation for studying effect of salicylic acid spraying on qualitative and quantitative characteristics in Rishbaba grape at grape orchard in 2013- 2014, performing in randomized complete block design with 4 repelication. The treatment in experiment was 150 mg/lit concentration of salicylic acid in 4 growth stages includes: vegetative growth, 50% of flowering, complete sour grapes, and three weeks before harvest. The results shows that applying salicylic acid increased cluster number in tree, cluster length, berries number in cluster, length and width of berries, average weight in 100 berries, juice volume, total sugar in fruit, titratable acidity and single seed weight in Rishbaba cultivar than control. Percentage of total soluble solids did not increase than control. In general, results of this research show that 150 mg/lit concentration of salicylic acid spraying has positive effect on improved growth stages and grape production.

Catharanthus roseus L., commonly known as the periwinkle, is one of the most important medicinal plants that included worthwhile alkaloids. The effect of the intensity and duration of magnetic field, medium strength and growth regulators were investigated on percentage of seeds germination. Sterilized seeds were exposed to different intensities of magnetic field (1, 2, 4mT) daily for 15 minutes during a week or a month. Treated seeds were cultured in MS or 1/2 MS media supplemented with different hormone combinations. Results indicated that application of MF for one month period caused the decrease in seed germination. To Investigate the hormone combination effect, the MF treated seeds were cultured in 1/2 MS media supplemented with 2,4-D and kinetine. In the presence of 2,4-D, the percentage of germination, production and growth of callus were increased. In the culture medium containing 2iP or Kinetin, seedling growth was performed without callus formation. Kinetine increased the number of shoots in a seedling without induction of callus production.

Aim: The aim of this study was to investigate the effects of different treatments of growth regulators on the amount of shooting, rooting, callus production and plant regeneration of hairless catmint (Nepeta nuda), in vitro condition.
Material and The seeds of this plant were cultured in MS/2, and then the plantlets were sub-cultured. The obtained samples were cultured in different levels of BA and Kinetin, either alone or in combination with IBA. Leaves of explants were used for callus induction with BA and NAA treatments in both medium (light and dark). Also, for regeneration, the same calluses were used with BA and NAA treatments.
The results of this study showed that, in proliferation part, the highest fresh weight (2315.9 mg) and shoot number (15.22 per each bush) of each plantlet were obtained in 1 mgL-1 BA and 0.25 mgL-1 IBA. Moreover, the BA treatment with 2 mgL-1 concentration cause to produce the longest branches (50.5 cm) and the highest number of nodes (53.6 per plantlet) in each plantlet.
The highest length, number and percentage of root were obtained at MS/2 medium and 0.5 mgL-1 IBA. In callus formation part, the highest fresh weight of callus was related to application of 1 mgL-1 BA with 0.5 mgL-1 NAA. In addition, the highest percentage of callus formation was observed in dark medium and no significant differences were observed between the growth regulator treatments. Furthermore, the highest percentage of regeneration of callus related to both growth regulators treatments included 1 mgL-1 BA with 0.2 mgL-1 NAA (83.2 %) and 1 mgL-1 BA with 0.5 mgL-1 NAA (81.66 %) with no significant differences between them.
In total, the most useful growth regulator compound for micro-propagation of hairless catmint, which is endangered extinction species, were 1 mgL-1 BA with 0.5 mgL-1 IBA and NAA.

Therapeutic effects of Hyoscyamus genus are attributed to its obtained different tropan alkaloids. Regarding these rare medicinal herbal species, tissue culture is of almost importance, as, it is possible to obtain optimal volumes of suitable secondary metabolite- producing-tissues with alteration in their culture media. Present study, H.arachnoideus Pojark, was investigated. Three types of explants (leaf, root, and hypocotyls) derived from seedlings, were cultured on Murashige and Skoog’s medium supplemented with 3% sucrose, 0.75% (w/v) agar. We investigated the effect of two types of carbon sources (sucrose and monitol) on Murashige and Skoog’s medium supplemented with 3% sucrose and 0.75% (w/v) agar in two explants types ( leaf and root) of H.arachnoideus with four concentration levels of auxin naphthalene acetic acid(0, 0.5, 1, 2 mg/l), in compare with Murashige and Skoog’s medium supplemented with 3% sucrose, 0.75% (w/v) agar as control, In order to determine callus biomass and total alkaloid content. Our findings revealed the bilateral role of sucrose both as nutrient source and osmotic regulator factor, and also showed the positive effect of sucrose on callus biomass and total alkaloid content.

Propagation of wild pistachio as a multipurpose woody species is a hard and tedious task. In this research، an effective in vitro protocol was developed for rapid proliferation of wild pistachio (Pistacia atlantica ssp. mutica) in MS medium supplemented with B5 vitamins and different growth regulators. Rooting of plantlets was tested by two treatments containing Rhizopon and IBA in ex vitro. With respect to the results، the nodal segments explants، produced the highest shoot frequency، leaf frequency and the tallest shoots. On the other hand، the tallest shoots were generated from shoot tip explant and medium containing of TDZ plus IAA. Both treatments (Rhizopon and IBA) led to a remarkable increase in the number of roots، root length and rooting percentage compared to the control. These results may be applied for rapid proliferation to spread the pistachio trees and shrubs that are difficult and time consuming.