ahmad sharifi

Gene transfer by the Agrobacterium tumefaciens is one of the well-known methods for the production of the transgenic plants. The success rate of this method depends on the growth of the bacteria and the regeneration of the plant explants. Among these variables, the antibiotics functioning as bacterial growth regulators have mainly inhibitory effects on the plant growth. Therefore, the introduction of a successful gene transfer method which is mediated by Agrobacterium requires the identification of an antibiotic with an inhibitory effect on the growth of the bacteria and also has a minimal effect on the regeneration of the explants and the growth of the transgenic plants. In this regard, the present research was conducted with the aim of optimizing the antibiotic used in co-culture in order to increase the transgenic yield of Petunia hybrida. For this purpose, a variety of antibiotics in different concentrations were tested.

The growth rate of A. tumefaciens in the different medium culture with two suitable pH for the bacterial growth (7) and plant growth (5.7) in the presence of 500 mg/L of the cefotaxime antibiotic as a common antibiotic for controlling bacterial growth was investigated. Sensitivity tests were run. The second experiment was conducted to investigate the effect of five different antibiotics in three concentration on the regeneration of the petunia leaf explants.

The results of the bacterial sensitivity test showed that the type and concentration of salt and the pH of the medium culture significantly affect the growth rate of the bacteria. So that the highest rate of bacterial growth was observed in LB and MH medium culture at pH=7, but on the contrary, no growth was observed in MS medium culture. In addition, two antibiotics of cefotaxime and ceftriaxone at 700 mg/L concentration had the highest inhibitory effect on the bacterial growth. The results of this experiment showed that different antibiotics have different effects on the regeneration of explants and the growth of the seedlings. According to the results, the highest volume of callus and also the highest percentage of regeneration were observed in the presence of ceftizoxime and coamoxiclav antibiotics in all three concentrations and cefepime at 300 mg/L. The highest number of the seedlings was also observed in the treatment of ceftizoxime at concentrations of 300 and 500 mg/L with an average of 7.70 seedlings. In relation to the seedling growth traits, the highest number and length of root per seedling were observed in ceftizoxime at 300 mg/l and cefotaxime at the same concentration, respectively. The highest dry weight belonged to the grown seedlings in the presence of co-amoxiclav antibiotic followed by the ceftizoxime (300 mg/L).

 The overall results of these experiments show that the seedlings which are grown in the presence of ceftizoxime antibiotic had a good growth rate, while the use of this antibiotic was effective in inhibiting the growth of A. tumefaciens. Therefore, we recommend that the use of ceftizoxime antibiotic in the co-culture process will be effective in increasing the efficiency of the gene transfer. Further studies will solidify these results.

Saintpaulia ionantha is a beautiful ornamental plant. to induce diversity by creating new genotypes of African violet in vitro Gamma ray and EMS were applied as physical and chemical mutagens respectively. Explants were cultured in MS medium containing 2 mg L-1 BA, 1 mg L-1 NAA, 30g L-1 sucrose and 7g L-1 agar. after two days they were treated with radiation (0, 20 and 40Gy) or EMS (0, 0.1, 0.3 and 0.6%). the dose of 40Gy and 0.3% and 0.6% of EMS reduced the regeneration of explants, the number of regenerated plantlets and leaves and caused enhanced variation and morphological changes. the color of leaves, their shapes and sizes were modified. afterwards genetic diversity of the mutant plants was investigated with ISSR marker. Eight primer pairs in PCR amplified different fragments of the genomic DNAs. Overall, 71 locations (bands) were scored. The dendrogram of cluster analysis using Jaccard coefficient and UPGMA algorithm showed high variability. The mutants were divided into 4 groups in similarity of 0.51%. Genetic similarity coefficient varied between 0.45-0.98 and 6 mutants were introduced based on morphological and molecular variations. the results showed in vitro mutagenesis of African violet by gamma radiation a suitable strategy to increase diversity.

For various reasons, such as lack of suitable land or architectural considerations, engineers may construct the foundation adjacent to or inside the slope body. Therefore, the problem of the bearing capacity of strip foundations placed on the slope and the safety factor of these slopes has been the focus of many researchers. On the other hand, especially in urban environments, the possibility of foundations being placed adjacent to each other is very high, and for this reason, the interference effect of nearby foundations is another challenge that researchers have investigated. In this research, these two challenges have been integrated and the interference effect of adjacent foundations placed on the body of the slope has been investigated using PLAXIS finite element software. In this way, one foundation is attached to the upper edge of the slope and the other foundation is considered inside the body of the slope. The parameters examined in this study are slope angle, slope length, soil friction angle, and soil cohesion. All of these parameters have been studied in the case of single footing and two interfering footings. The results indicate that an increase in the angle and length of the slope causes a decrease in the bearing capacity of the footing and a decrease in the safety factor of the slope. Also, with the increase of cohesion and friction angle, the bearing capacity of the footing and the safety factor of the slope increased. The interference effect caused an increase in the bearing capacity and a decrease in the safety factor, and by increasing the length of the slope more than 5B at different angles of the slope, the interference effect disappeared.

Plants are exposed to various environmental stresses during growth and development under natural and agricultural conditions. Drought is one of the most severe abiotic stresses that greatly affects plant yield. Metabolic changes under stress cause the morphological and physiological changes in the plant which may eventually lead to reduced yield. Barley is one of the most important cereals which a large part of the human population in many parts of the world are dependent on it as a source of food and animal feed.

In order to investigate the effects of drought stress on some morphological and physiological traits in barley as one of the most important crop, this experiment was carried out in the greenhouse of the agriculture faculty, Ferdowsi University of Mashhad in 2019 in a factorial based on a randomized complete block design with three replications. Experimental factors were included: different levels of drought stress including 100% of field capacity (control or no stress), 80, 60 and 40% of field capacity and two barley cultivars containing semi-sensitive (Fajr30) and drought tolerant (Dasht). First, the seeds of both cultivars were planted in trays filled with coco peat, perlite and sand, and after two weeks, the seedlings were transferred to pots filled with garden soil. The pots were watered daily and after one month (4 to 6 leaf stage) until the end of the growing season, they were subjected to drought stress treatments. During the vegetative stage, morphological traits such as plant height (from crown to end of plant), stem diameter, number of leaves, number of tillers, leaf area and number of stomata below and above the leaf were examined using common methods. Physiological traits including proline, soluble sugars, photosynthetic pigments and antioxidant enzymes (catalase and peroxidase) were also measured. Analysis of variance was performed using JMP statistical software version 8 and the mean of treatments was compared using LSD test at the level of 5%.

The results of this experiment showed that the effect of cultivar and drought stress were significant for many of the studied traits. The highest plant height, stem diameter, number of leaves and tillers and leaf area index were observed in plants without stress (100% FC), which was significant compared to other stress level. Also, the comparison of the two cultivars showed that Dasht, as a drought tolerant cultivar, has more leaves and tillers but less leaf area and stomata than the semi-sensitive cultivar Fajr30. In other words, the tolerant cultivar produces more leaves but smaller under stress condition which finally reduces the leaf area compared to the sensitive cultivar. This can be a good solution for drought resistance through reduce evaporation from the leaf surface as well as shading. In addition, osmotic regulators such as proline and soluble sugars and the activity of antioxidant enzymes including catalase and peroxidase increased under drought stress and it was higher in tolerant cultivar. In fact, it seems that tolerant cultivar can tolerate drought stress through activating their immune system by producing osmoprotectant and increasing the activity of antioxidant enzymes.

In general, results showed that proline, soluble sugars and antioxidant enzymes play a role in the mechanism of stress tolerance and their metabolism is affected by drought stress. The results of this experiment suggest that the accumulation of these osmoprotectans and morphological changes can be part of the drought resistance mechanisms in the drought tolerant genotype of barley, which can ultimately be used in breeding programs to improve drought tolerance. In general, the results of this experiment showed that both barley cultivars responded to drought stress, but Dasht cultivar showed more tolerance in these conditions.

Small non-coding RNAs known as microRNAs are essential for responding to biotic and abiotic stresses. A few microRNAs that exhibited varied expressions in the face of drought stress are miR393, miR159, miR169, and miR319. This study examined how these four microRNAs helped petunia deal with drought stress. A 50% drought stress was applied to the petunia plants in the 4 to 6-leave stage, and RNA was isolated from both stressed and control plants. The expression level of microRNAs was examined using the qRT-PCR method under two conditions: control and stress. The data obtained indicated that the expression level of miR319 remained unchanged, while miR393 showed a decrease in expression, and miR169 and miR159 showed increases of 4 and 6.5-fold, respectively.

Narcissus tazetta L. is one of the most important flowering bulbous plants that are traditionally propagated by bulb splitting which is a costly and time-consuming method. Therefore, the application of in vitro culture techniques can help to increase the reproduction coefficient of this ornamental plant. So, the study was conducted in two separate experiments. In the first experiment, the effect of twin scales position on the mother bulb on the regeneration of twin scales of Narcissus were investigated in MS medium containing 1mg/l BA in combination with 0.2mg/l NAA in a completely randomized design. In the second experiment, the effect of different types of auxin on rooting of Narcissus plantlets was investigated. For this purpose, ½MS medium containing 1 mg/L NAA, IBA, IAA and hormone-free medium was used. The results showed that the application of different layers of Narcissus twin scales had a significant effect on the number and diameter of regenerated bulblet. In fact, application of the inner scales of mother bulb led to an increase in the number of regenerated bulblet, but the diameter of regenerated bulblet decreased. Since the diameter and number of regenerated bulblet are both important parameters during in vitro culture conditions, it is recommended to use twin scales group one and two for propagation of Narcissus bulb. The results of this study also showed the superiority of hormone-free ½MS medium and ½ MS medium containing 1 mg/l IAA for rooting of Narcissus tissue culture plantlets.

African violet (Saintpaulia ionanta) as a valuable potted ornamental plant needs to create new cultivar. The aim of this study was to investigate the induction of mutations using gamma ray and EMS (Ethyl methane sulfonate) on African violet under in vitro condition. Leaf, petiole and plantlet explants were obtained from sterile plantlets in MS culture medium containing 2 mg/l BA, 0.2 mg/l NAA, and 30 g/l sucrose with 7 g/l agar. Explants were treated with 0, 20 and 40 Gy of gamma rays or 0, 0.1, 0.3 and 0.6% EMS. Results shown with increasing the dose of gamma rays and EMS, the survival percentage and the number of regenerated plantlets reduced. Also, with increasing the dose of gamma rays, diversity and leaf morphological changes in form of color, shape, size and twisting increased but no visible changes in treated plants with EMS. In conclusion gamma irradiation under in vitro condition can be used as a suitable strategy to increase diversity in African violet.

Cellulose which is extremely produced by plants, can be used for biofuel production but this function needs chemical or enzymatic digestion. Cellulose hydrolysis of plant wastes for ethanol production requires a mixture of three enzyme groups, including endoglucanases, exoglucanases, and beta-glucosidases. The cellobiohydrolase enzyme (Cel6B) from Thermobifidia fusca has been used for cellulase activity extensively. This research aimed to express recombinant Cel6B enzyme in Pichia pastoris. For this purpose, cel6B gene in control of AOX1 promoter (methanol inducible) was introduced into Pichia pastoris. Amplification of cel6B gene was performed by PCR technique and then introduced into the Phil-S1 yeast vector. The recombinant construct contained the cel6B gene sequence and PHO1 signal sequence as secretion signal was transferred into Pichia pastoris GS115 strain. The transformed yeast cells expressed the recombinant Cel6B to yield 2.104 U (µmol/min)/ml of culture medium. Purified recombinant enzyme showed the best activity at 60 °C and pH 4.5 and this was agreed with optimum conditions for recombinant Cel6B enzymes which were produced in other systems. The purity of the enzyme was examined by SDS–PAGE technique, and a single band with a molecular weight about 59.6 kDa was observed. As cel6B gene sequence was not optimized for expression in the Pichia pastoris yeast, this could be one of the reasons for low level activity of recombinant Cel6B enzyme. This thermostable enzyme can be used for cellulolytic digestion of biomaterials in biofuel production research and other uses.

To optimize the bioassay system of auxin hormones by identifying their effect on the growth of Arabidopsis plants under in vitro conditions, Arabidopsis seeds were germinated vertically in ½ MS medium. After 5 days, seedlings with the same root growth were transferred to ½MS medium culture containing IAA, IBA, NAA, and 2,4-D hormones with concentrations of 0, 0.01, 0.03, and 0.05 mg/ L. After 10 days, plant growth characteristics were measured using image analysis plus the fresh and dry weight of seedlings in each treatment. The different hormones had different effects on the growth. Increasing the concentration of IAA, IBA, and NAA hormones caused the reduction of the rootlets’ induction. The use of different concentrations of 2,4-D hormone prevented the growth of roots. Higher concentrations resulted in the production of callus in the roots. The concentration of 0.01 mg/L of the examined auxin hormones mostly had the highest rate of leaf formation and biomass production. This bioassay method can distinguish the effects of different auxin hormones on different aspects of plant growth. The results can help in selecting the required auxin hormone in various activities and make it possible to identify unknown auxin compounds. IntroductionPlant hormones perform different biological functions in different tissues according to the growth stage or in response to environmental conditions. Evidence shows that the response of the plant to different types of auxin is different from each other and the activity of each of these hormones causes the activation of a range of different physiological processes in the plant. On the other hand, all lateral root growth stages are dependent on the amount of intracellular auxin hormone accumulation. Despite the similarity, these hormones are functionally different due to differences in structure which affect their signal transmission and downstream physiological pathways. Therefore, it is necessary to optimize a bioassay system to identify and differentiate the auxin hormones based on their biological effects, so we tried measuring the performance of different concentrations of auxin hormones. Materials and MethodsThe effects of different levels of auxin on Arabidopsis thaliana (Columbia cultivars) seedlings were investigated and ½MS medium culture containing 1% sucrose and 0.75% agar. The pH of the medium culture was set at 5.8 ± 0.1 and autoclaved at 121°C for 20 minutes. The seeds were disinfected with 1% sodium hypochlorite and sterile distilled water for 10 minutes and were cultured in ½MS without hormones. The petri dishes were placed vertically in the growth room for 5 days. The seedlings with 1 cm roots length were selected and in the 4 hormonal treatments, medium cultures were sub-cultured including IBA, 2,4-D, IAA, and NAA in three concentrations of 0.01, 0.03, and 0.05 mg/L, as well as the control treatment without hormones with three replications. Hormones were added to the sterile medium culture after passing through a 2 μm filter. After 10 days, the number of leaves, root length, the number of lateral roots, and fresh weight were measured. The growth level of the shoot and root and the level of greenness of seedling leaves were performed using image analysis and ImageJ software, dry weight of the seedlings was measured after exposure to 72°C for 48 hours. All treatments were analyzed using one-way ANOVA. The mean comparison of treatments was performed by LSD test with a minimum significant difference at a 5% probability level using JMP software (version 8.0). Graphs were also drawn using Excel software.  Results and DiscussionThe presence of auxin in different concentrations inhibits the root length growth and the control seedlings showed the highest root length growth. Seedlings grown at the high concentrations of NAA and in the presence of 2,4-D had the lowest root length with an average of one cm. Seedlings grown in NAA hormone treatment with a concentration of 0.01 mg/L had the highest rootlets number. However, the roots formed in the presence of 2,4-D and high concentrations of NAA produced callus and did not grow normally. The root area in the presence of IBA was more than IAA. The number of seedling leaves grown at 0.01 mg/L concentration of hormones was equal to or more than the higher concentrations of these hormones. The lowest number of leaves belonged to the seedlings grown in 0.03 mg/L NAA and 0.05 mg/L 2,4-D treatments. IAA concentration had a direct relationship with leaf area and with the increase in the concentration of this hormone the leaf area increased, but the use of IBA had the opposite effect on leaf area and decreased with increasing its concentration. The highest leaf greenness was observed in three concentrations of 2,4-D and then in the control. The use of other auxin in the medium culture inhibited the production of chlorophyll in the cells. After the use of auxin in Arabidopsis plants, the fresh and dry weight of the seedlings grown in the presence of the concentration of 0.01 mg/L of NAA had the highest fresh and dry weight. ConclusionThe effect of auxin hormones on different aspects of plant growth was different from each other. IAA increased the number of rootlets and low concentration and formed many rootlets on the main root. High concentrations led to an increase in the number of lateral roots, but the root length significantly decreased. Also, 2,4-D stimulated callus production in the roots. The presence of IBA in the medium culture decreased the average root length. The difference in the morphological effects of different auxin hormones can be considered a road map that will provide the possibility of identifying the auxin hormone in unknown extracts in future research.

Vinasse is one of the by-products of alcohol and yeast companies that use molasses as a raw material. The production of this substance is very high in the industry and the release of Vinasse in nature has environmental damage due to the large amounts of organic and inorganic materials. Today, the possibility of using this substance in low concentrations as organic fertilizer in agriculture has been proposed. Using Vinasse as an organic fertilizer is a simplest and most practical way to reduce waste.

In this regard, this experiment was conducted with the aim of investigating the use of Vinasse as fertigation on the growth traits of cucumber (Cucumis sativus L.) in a completely randomized design with four replications. Cucumber seeds of hybrid cultivar (super max F1) with 99% purity were used. In order to seed germination and seedling production, seeds were cultured in cocopeat+perlite (1:1) and placed in the growth chamber. After seven days from seed sowing, experimental treatments were applied. Treatments included 1) hogland fertilizer, 2) diluted Vinasse, 3) hogland fertilizer+diluted Vinasse, 4) ½ hogland fertilizer+½ diluted Vinasse. After 7 weeks, plants were collected and growth parameters were measured. The investigated morphological traits included the number of leaves, fresh and dry weight of leaves, fresh and dry weight of roots, fresh and dry weight of stems, volume of roots, length and diameter of stems, as well as leaf surface. The plant leaf area was measured using ImageJ 1.52v software. Also, physiological traits such as relative water content (Barrs & Weatherley, 1962), electrolyte leakage (Marcum, 1998), pigment content (chlorophyll index, chlorophyll a, b, total chlorophyll and carotenoid) (Dere et al., 1998), protein (Bradford, 1976), proline (Bathes et al., 1973) and leaf nitrogen were measured by kjeldahl method (Page et al., 1982). Statistical analysis of data was done using JMP-8 software and mean comparison was done using LSD test.

The use of Hoagland nutrient solution alone led to an increase in the number of leaves in the plant compared to other fertilizer treatments and recorded the highest leaf fresh weight (4.52 grams) and leaf dry weight (0.35 grams). Meanwhile, the combined use of Vinasse and Hoagland nutrient solution in full concentration was able to increase the leaf area in the plant and the highest amount of leaf area (29.21 cubic centimeters) was recorded in this treatment. Root fresh weight was affected by the combined treatment of Vinasse and Hoagland nutrient solution in half concentration and it increased significantly (1.89 grams) compared to other treatments. The application of Vinasse alone could only lead to the production of the highest dry weight of the stem (0.23 grams) compared to other experimental treatments. Although the complete Hoagland fertilizer treatment showed good results in the development of the root system, the use of the combination of Hoagland and Vinasse nutrient solution in half concentration showed a more appropriate response. Results showed that plants treated with Vinasse entered the reproductive phase faster than other experimental treatments. Vinasse contains significant amounts of potassium and organic matter (Kusumaningtyas et al., 2017). The rapid flowering of Vinasse-treated plants is probably due to the high potassium content of this organic fertilizer and the reduction in nitrogen content. The use of Vinasse as a fertigation in plants leads to the enrichment of microelements in the substrate (Kogani et al., 2018), and due to the abundance of organic matter in Vinasse, it is an important source of nutrients that is suitable for plant growth (Madejon et al., 2001). However, according to the results of this experiment, it was determined that application of Vinasse alone is not able to meet the nutritional needs of the cucumber plant. The use of hogland fertilizer + diluted Vinasse improves the growth traits of the plant such as leaf number, root fresh weight, root dry weight, leaf dry weight and leaf area. The use of diluted Vinasse reduced the chlorophyll content and increased the proline.

In general, Vinasse is not a complete fertilizer because of the low nitrogen content. So it needs to be combined with other nitrogen fertilizers. However, this fertilizer can be used in the reproductive growth stage when the plant needs lower amounts of nitrogen.

Haworthia cooperi is a type of ornamental succulent that is propagated by separating the offsets and leaf cuttings. Due to the small number of produced offsets by the mother plant, the rate of propagation in this way is low, so micropropagation can be considered as an effective and efficient way to propagate this ornamental plant.

For this purpose, in the present study, the growth response of Haworthia cooperi plants to in vitro culture conditions in 1398 in the research laboratory of the Department of Ornamental Plants Biotechnology was investigated. This research was conducted in the form of three separate experiments based on a completely randomized design with three replications. In the first experiment, the effects of cytokinin type (BA and KIN) and concentration of cytokinin (0, 1, 2 and 3 mg/l) on leaf explant regeneration were evaluated. In the second experiment, the effects of culture medium type (MS and B5) and concentration of culture medium (0.5 and 1) on plantlet propagation were investigated. In the third experiment, plantlet rooting rate was evaluated under the influence of auxin type (NAA, IBA and IAA) and concentration (0, 0.5, 1 and 1.5 mg/l) of auxin.

The results showed that application of BA and KIN hormones increased the number of regenerated plantlets. The highest number of plantlets (5.50) was recorded in the MS medium containing 3 mg/l BA with 0.5 mg/l NAA. Plantlets cultured in the hormone-free culture medium had no regenerated symptoms. The number of plantlets increased with increasing the concentration of both hormones, but BA hormone in the culture medium had a greater effect on this factor. Lack of cytokinin hormone application in culture medium led to root production; however, the use of BA and KIN hormones in the culture medium reduced the number of produced roots by plantlets. The highest number of roots was recorded in hormone-free culture medium and the lowest number was recorded in the high concentration of BA hormone. The reduction in the number of roots in the culture medium containing BA was greater than the culture medium containing KIN. The of the second experiment revealed that use of MS culture medium showed better performance compared to B5 culture medium. Thus, the highest dry weight of plantlet and roots was obtained at full concentration of MS culture medium. The results of rooting stage showed that the presence of NAA hormone in the culture medium increased rooting in the plant. However, the produced roots in this culture medium were so thick that these roots are not suitable for plant growth in the acclimation stage. Therefore, considering the number and length of produced roots, the optimal culture medium for plantlet rooting is ½ MS culture medium containing 1 mg/l IAA hormone. Determining the best type of culture medium and optimizing it for regeneration, proliferation and rooting is one of the important factors in success in vitro culture conditions. Based on the results of the current study, application of MS medium containing 3 mg/l BA with 0.5 mg/l NAA was so effective for regeneration phase of this ornamental plant. Also, the efficiency of MS culture medium in the process of propagation of this plant is most likely related to the suitability of the components of this culture medium. In general, due to the presence of plant growth regulators such as NAA, IBA and IAA in the culture medium, rooting is induced in plantlets. In the present study, the use of IAA hormone at a concentration of 1 mg/l was a suitable hormonal combination for rooting in this ornamental plant.

Based on the results of the present study, the application of MS culture medium containing 3 mg/l BA with 0.5 mg/l NAA is recommended for regeneration and proliferation of tissue culture plantlets of Haworthia cooperi. It is also recommended to use ½ MS culture medium containing 1 mg/l of IAA hormone for rooting of tissue culture plantlets.

This research includes the design, manufacturing, and evaluation of a live mulch planter unit. In order to address the problems of using agricultural machinery in performing live mulch planting in the furrows or simultaneously with the main crop, a prototype planting unit was designed. In this planter, a seed-drop plate was used to convey the seeds from the metering device to the ground. The result of this project was a prototype of a planter with the ability to plant 19.6 to 163.2 grams per minute of live mulch (hairy vetch) with a tolerance of 0.54 grams along the entire width of a 75 cm furrow. Laboratory and field experiments were conducted to evaluate its performance in actual field conditions, based on planting accuracy and field efficiency. The Laboratory test was performed according to ASAE S341.2 DEC92 standard for Grain Drill evaluation. Results of the initial evaluation of the planter showed that changing the rotational speed of the metering device significantly affected seed output on the drop plate in terms of seeding rate. The position of the outlets did not differ significantly in terms of seed damage. Increasing rotational speed of the metering device significantly increased the tendency of metering mechanism to damage seeds. Increasing rotational speed of the metering device significantly decreased index of non-uniformity in all outlets.Results of the initial evaluation of the planter showed that changing the rotational speed of the metering device significantly affected seed output on the drop plate in terms of seeding rate. The position of the outlets did not differ significantly in terms of seed damage. Increasing rotational speed of the metering device significantly increased the tendency of metering mechanism to damage seeds. Increasing rotational speed of the metering device significantly decreased index of non-uniformity in all outlets.

Thalictrum minus L. is a medicinal plant contains berberine, which is used for complementary treating of some diseases. Excessive harvesting of this species from rangelands to extract the alkaloid has endangered its survival.

This study was aimed for in vitro propagation of this species and berberine production.

The seeds were germinated at in vitro culture conditions. Then, the leaves were used as explants for callus induction in two MS and LS basal media supplemented with BA (0, 0.1, 0.5 and 1 mg/L) in combination with different concentrations of auxins, NAA, 2,4-D or IAA.

The results showed that MS medium with the plant growth regulator combination of 0.5 mg/L BA and 0.5 mg/L NAA had the highest callus formation and 100 % regeneration. Some calli were transferred to three liquid culture media (MS, LS, or ½ MS) with 1 mg/L BA + 0.1 mg/L NAA or without plant growth regulator to produce the berberine. The HPLC results identified 6 % of berberine in the liquid medium. This amount of berberine can be easily released into the culture medium, therefore, it will be easier to extract. 

This method can be successfully used for propagation and extraction of berberine without plant destruction.

Gerbera is one of the most important cut flower and potted plant that normally propagated via tissue culture tecniques. For the suitable adaptation of plantlets in tissue culture, having a strong rooting system is crucial. So, in this study the effect of culture medium type, sucrose and hormonal combination on rooting of Gerbera plantlets was investigated. Factorial experiment was conducted in a completely randomized design with 3 factors and 4 replications. Before culturing, plantlets were immersed in GA3 (5 mg/l), GA3 (2.5 mg/l) + IAA (5 mg/l) and distilled water for 5 minutes and after that, they were cultured in ½ MS or modified White media. Also, in order to investigate the effect of sucrose on rooting of explants, the concentrations of 0 (control) and 30 g/l sucrose were used in the culture media. At the end of the experiment, different traits were measured. Results showed that the produced plantlet in the non-sucrose medium had the shorter roots and the use of sucrose in the culture medium increased root length by more than 2.5 times. Also, in the absence of sucrose, the primary and secondary root number fell sharply and the weight of plantlet reduced. Hormon-free ½ MS medium containing 30 g/l sucrose led to the production of maximum secondary root number and dry weight as well as an acceptable number of main root. So, for in vitro rooting of gerbera plantlets, application of hormon-free ½ MS medium supplemented with sucrose is recommended.

Amaryllis is one of the ornamental bulbous plants that its proliferation is commercially slow. Application of tissue culture techniques can be a suitable way to increase the propagation rate of this ornamental plant. This study was conducted in two separate experiments. In the first experiment, the effect of light condition and position of twin scales in the mother bulb was evaluated on the regeneration of Amaryllis twin scales. In the second experiment, the effects of different concentrations of sucrose (30, 60 and 90 g/l) and the position of twin scales in the mother bulb investigated. MS medium containing 0.5 mg/l BA+0.1 mg/l NAA was used. Experiments were carried out in a factorial arrangement with five replications in a completely randomized design. Results showed that 16-hour light condition lead to production of more bulblets than dark condition. In terms of bulblet diameter, the brightness conditions were superior to the dark condition. The findings of this study showed the superiority of the outermost twin scales compared to innermost twin scales. Bulblets regenerated from twin scale group 1 were thicker than the other treatments and their dry weight was also higher. Application of sucrose at a concentration of 60 g /l to the culture medium resulted in the production of bulblets with the highest dry weight. By increasing the concentration of sucrose from 60 to 90 g/ l, there was a significant decrease in the regenerated bulblet diameter. Generally, application of medium containing 60 g/l sucrose, twin scales group 1 and 16-hour light conditions is recommended to increase the multiplication rate of Amaryllis.

Begonia is one of the most important ornamental plants around the world. Begonia species are grown for their attractive leaves and flowers in indoor and outdoor conditions. The tissue culture technique is an alternative method for the propagation of begonia species. It can overcome the difficulties of vegetative propagation and lead to high-quality and uniform planting material under disease-free conditions irrespective of the season and weather. In begonia tissue culture, different species showed diverse responses to the medium composition, especially plant growth regulators. Also, lack of information on large scale micropropagation of begonia in Iran highlights research on optimization of begonia species propagation on in vitro culture condition. Thus, in this study the effect of plant growth regulators on shoot regeneration and proliferation of three begonia species (B. elatior‌, B. soli-mutata, and B. tiger), the impact of Auxin and sucrose on rooting of B. elatior‌and diferent pot substrate on acclimation were survived.

In this experiment, petioles of three begonia species (B. soli-mutata, B. elatior, and B. tiger) were used as explant sources. So explants were washed under tab water for 30 mins and sterilized with 1.5% sodium hypochlorite for 15 mins. After sterilization, thin Cell Layers (TCL) with 2 mm thickness were prepared from petiols and cultured in MS medium with different concentrations (0.2, 1, 2 mg/L) of kinetin (kin) or thidiazuron (TDZ) in combination with NAA (0, 0.2 mg/L). Next, the effect of auxin type (1 mg/L of IAA, IBA, and NAA) and sucrose concentration (30 and 40 g/l) on rooting of B. elatior plantlets were determined on in vitro condition. For plantlet acclimation, sand, CocoPeat perlite mixture (1:1 ratio), and Peat moss as pot substrate were evaluated.

The results showed the shoot regeneration response of begonia species to the plant growth regulators of the medium, and there was a significant difference between them in all of the species adding the Auxin to the medium increased shoot regeneration. In B. elatior and B. tiger lacking of NAA to the medium caused no shoot regeneration. Maximum shoot regeneration (100%) was achieved in B. soli-mutata species in medium containing 1 or 2 mg/L of kin and 0.2 mg/l NAA, in B. elatior at 1 or 2 mg/L of TDZ in combination with 0.2 mg/l NAA and in B. tiger at 2 mg/L of both plant growth regulator (TDZ and Kin) and 0.2 mg/l NAA.

For rooting B. elatior, MS medium containing 1 mg/L IAA plus 30 g/L sucrose was the best and favorite acclimation was acheived in cocopeat perlite mixture and peat moss pot substrate.

Pomegranate (Punica granatum L.) is a fruit tree that originated from Iran and has been cultivated since ancient times. Classical propagation methods of pomegranate like stem cutting and air-layering have seasonal timing and a higher risk of pathogens contamination. Micropropagation by tissue culture could be considered a method for production of steady and pathogen free plants in this species. However, factors such as lack of rooting and browning due to the oxidation of phenolic components under invitro culture can limit its micropropagation efficiency. To overcome these problems, the effects of various factors, including media, iron-chelating agent, and plant growth regulators, were examined on the pomegranate propagation through in vitro conditions.

To obtain sterile explants, stem cuttings of the pomegranate cultivar Shishe Cap Ferdos were treated with different disinfection treatments. Then, the effect of DKW, MS and WPM basal media and two types of iron chelating agents (EDDHA and EDTA) were evaluated to decrease the secretion of phenolic compound from explant and subsequent browning. In the next step, the effect of plant growth regulators treatments, including 1-2 mg/l of BA in combination with 0.2 mg/l of various auxins (IAA, NAA or IBA) on shoot development and proliferation was studied. After that, rooting of regenerated plantlets was explored at WPM medium supplemented with 0.5 or 1 mg/l IAA, IBA or NAA. Finally, pomegranate plantlets were transferred to different soil mixtures, including eat moss and perlite (2:1), cocopeat and perlite (2:1), peat moss and vermiculite (2:1) and cocopeat and vermiculite (2: 1) for acclimation.

The results indicated that sterilization with 2% sodium hypochlorite for 15 minutes followed by washing with 1g/l carbendazim for 10 minutes, and finally culturing the explants in the medium containing 1 g/l carbendazim had the best effect on reducing explant contamination. Among different basal media and iron chelating agents, WPM resulted in the lowest explant browning. Also, EDDHA was more efficient compared to the EDTA so that explant browning in WPM media containing Fe-EDDHA reduced by 55.8% compared to DKW containing Fe-EDTA. In addition, WPM basal medium supplemented with 2 mg/l BA and 0.2 mg/l IAA induced higher shoot proliferation in node explant of pomegranate. For rooting treatments, after 45 days, WPM supplemented with 1 mg/l IAA induced higher rooting percentage, root length and number in pomegranate shoots. Among different acclimatizing treatments, plantlets that grew on peat moss and perlite (2: 1) had the highest leaf number and stem height.

Our results suggested that the medium composition and chelating agent affected pomegranate explants browning. EDDHA appears to have a positive effect on reducing browning by chelating copper, which is a phenol oxidase cofactor. Also, EDDHA was more efficient compared to the EDTA.

Amaryllis is one of the ornamental bulbous plants, whose reproduction occurs slowly in natural conditions. Therefore, using tissue culture technique can be a suitable way to increase the multiplication rate of this ornamental plant.

In this study, a factorial experiment was conducted in a completely randomized design with 5 replications. The effect of different concentrations of BA and Kin (0, 0.5, 1 and 2 mg/L) in combination with 0.1 mg/L NAA on regeneration of different twin scale type of amaryllis was evaluated. Explants were divided as twin scales and classified in 4 groups, so that the outermost twin scales was grouped in class 1 and the innermost twin scales was grouped in class 4.

The results showed that the diameter of produced bulblet was influenced by the position of the twin scales in the mother bulb. The twin scale group one, which was made from the outer layers of the bulb, produced thicker bulblets, while the twin scales group four showed the minimum average of this trait. However, the explants cultured in a culture medium containing 0.5 mg/l BA in combination with 0.1 mg/l NAA had the highest bulblet diameter.

Generally, the application of twin scales group 1 and MS medium containing 0.5 mg/l BA in combination with 0.1 mg/l NAA is recommended for regeneration and proliferation of Amaryllis twin scale explants.

Begonias are popular ornamental plants in the world so introducing of various forms of this plant is very important. Nowadays plant modification through biotechnology and genetic engineering for production of new genotypes with varied forms is highlighted in this genus. So optimization of regeneration in in vitro culture condition and gene transferring is in priority to provide a suitable condition for gene transferring in this plant specially those responsible in flower color.
 
In the first step, thin cell layer (TCL) explants from petioles of B. soli-mutata were assayed in MS medium containing Kin or TDZ (0.2, 1 and 2 mg/l) in combination with NAA (0 and 0.2 mg/l). For co-culturing of petiole TCL explants with Agrobacterium tumefacians strain LBA4404 containing GUS and NPTII genes MS medium supplemented with 1 mg/l Kin and 0.2 mg/l NAA was used. Transformed plantlets were confirmed by PCR and Gus assay test.
 
Based on the regeneration results, Kin was better than TDZ, also adding NAA to the medium has positive effect on both of cytokinins. In transformation process, out of 2000 explants which infected with Agrobacterium, after 4 months of culture only 17 plantlets were adopted. Of these 17 plantlets, only 7 plantlets were confirmed by Gus assay test and PCR as transgenic plants.
 
The result showed in this species transformation percentage is low and optimization of transformation condition is important.

Cocopeat: perlite mix is a common substrate in gerbera commercial production. With regard to the uncontrolled import of cocopeat from Southeast Asia, replacing this substrate with domestic production substrates could be an effective step to reduce dependence on imports of primary inputs for production. In this study, the effects of different types of substrates on the vegetative and reproductive stages of Gerbera were evaluated in a randomized complete block design with 8 treatments in 6 replications. Growth parameters including number of produced leaves, fresh and dry weight of shoot, chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, fresh and dry weight of roots, leaf chlorosis percentage, leaf necrosis percentage, flower number, flower diameter, stalk height, number of days to flowering, middle diameter of stalk, end diameter of stalk and vase life were investigated. The results showed that plantlets grown in mushroom compost: perlite and then sandy substrate had the highest leaf number, shoot and root dry weight, indicating high potential for entering the reproductive phase. The lowest number of days to flowering and the highest number of flowers were obtained in these two culture media. Plants that were treated with sawdust: perlite and perlite did not show desirable vegetative and reproductive growth and due to high substrate EC in leaf mold: perlite, the percentage of leaf chlorosis and necrosis was significant.

Burnout is a work-related stress syndrome that has become a significant problem among health care providers. Burnout is associated with a decrease in occupational well-being and an increase in absenteeism and illness. In particular, nurses are vulnerable to exhaustion because of their job characteristics, such as unpredictability, overcrowding and continuous exposure to a broad range of diseases, injuries and traumatic events. This study aims to investigate the moderating role of procrastination on the relation between job demands and resources with burnout. In this regard, 152 nurses (65 male, 74 female) from seven hospitals, which were selected based on convenience, in Mashhad have participated in this study. They completed the Job Content Questionnaire (JCQ), Maslach Burnout Inventory-Human Service Survey (MBI-HSS) and Pure Procrastination Scale (PPS). The results indicate a statistically significant positive correlation between job demands and MBI scales. Also, a statistically significant negative correlation was obtained between job resources and MBI scales. These findings indicate that job demands promote chronic stress in nurses, while job resources protect them from burnout. Procrastination was also found to moderate the relation between some job resources and ineffectiveness. These findings show that a simple linear relationship between job demands-resources with exhaustion does not exist, and suggest personal demands, such as procrastination, as a moderator in this relationship. Incorporating own requests in burnout models is expected to enhance the current burnout prevention strategies.

One of the most important issues in agricultural machinery section is tyre - soil interactions. In this study, a single wheel tester was used to follow experiments in controlled conditions in a soil bin. A Goodyear 12.4-28, 6 ply tractor drive tyre was operated at three vertical loads of 6, 9 and 12 kN, three inflation pressures of 80, 120 and 160 kPa and three moisture content of soil: 11.20, 14.86 and 18.68 % d.b to investigate the effect of the variables on these parameters: contact area, contact pressure, compaction, and soil apparent electrical conductivity. It was found that medium contact pressure had a direct relation with vertical load, inflation pressure and moisture content. A regression model with R-square of 0.946 was achieved to predict contact pressure. Soil electrical conductivity changes was predicted with acceptable determination coefficient of 0.850 by using of vertical load, inflation pressure and moisture content. Determination coefficient magnitude for models to predict resistance to soil penetration (cone index) using soil apparent electrical conductivity decreased when moisture content was increased. The vertical load and inflation pressure were found two factors controlling the soil apparent electrical conductivity changes in low and high moisture content, respectively. Error percentage in using soil apparent electrical conductivity parameter to estimate the penetration resistance increased with increasing moisture content.

Regarding numerous studies in the literature involving Goldberg’s big 5 factor inventory (BFI), it is safe to assume that factor structure of BFI is highly valid. The main goal of this study is to assess whether network analysis can reproduce the results of exploratory factor analysis and if so, will the plotted network of items provide new insights? In the present study, the network structure of 25 items of BFI will be presented by conducting network analysis and cluster analysis; In addition, the results of network analysis will be compared with findings from exploratory factor analysis. The statistical population encompasses all people from different countries who voluntarily referred to website of international personality item pool and took part in the English version of Goldberg’s big 5 factor personality assessment tool. The data sample includes 2800 people from statistical population who referred to this website in the spring of 2010. All the statistical analysis has been carried out in R statistical software (version: 3.4.4). The network analysis using Gaussian graphical modeling alongside cluster analysis was able to accurately categorize the 25 items in 5 subgraphs in complete accordance with exploratory factor analysis results. In addition, items corresponding to extraversion sit in the center of the graph which denotes the importance of extraversion among other factors. Last but not least, the centrality analysis revealed invaluable information regarding the role and importance of items in the personality questionnaire.

Application of stress-tolerant rootstocks is known as one of the effective methods to enhance the productivity of fruit gardens. Pear is one of the four or five major classes of fruits that are produced worldwide. Among pear cultivars, Pyrodwarf rootstock is tolerant to alkaline soil and low temperatures of winter. In addition, many cultivars of pear with high productivity could be grafted to this rootstock. These advantages result in widespread culture of pyrodwarf rootstock in pear gardens. The increasing market demand of this rootstock presents an opportunity to investigate alternative methods for efficient production of pyrodwarf. Therefore, this study has been conducted to increase the efficiency of pyrodwarf propagation through tissue culture methods. For this experiment, sterile plantlets of pyrodwarf rootstocks in a same growth phase were used. Plantlets were cultured in different 12 media including MS, WPM, KNOP, modified KNOP, QL and modified QL basal media supplemented with 0.5 mg.L-1 BA and 0.05 mg.L-1 IAA or IBA and solidified with 8 g.L-1 agar. After that, cultures were transferred to the growth room at 25 ± 1°C under a 16/8h light/dark photoperiod (light intensity 30 μmol.m−2.s−1, cool-white fluorescent light). In the next step for rooting optimization, two separate experiments were conducted. In the first, 10 different basal media containing various nutritional compounds were examined for rooting properties of pyrodwarf plantlets. The following experiment was performed to reveal the effects of IAA and active charcoal on the efficiency of plantlets rooting. All the experiments were carried out in acompletelyrandomized design. The study of propagation efficiency of plantlets was arranged in a factorial approach with twofactors including the type of basal media (sixlevels) and auxins (twolevels) with threereplications. The both experiments of plantlet rooting were performed with sevenreplications. Data were analyzed using JMP-8 statistical software and the meanswere compared by using LSD test at 5% probability. All explants were regenerated 15 days after cultivation. The number of buds per explants indicates that nutritional compounds significantly affected bud formation. MS basal media induced the most number of adventitious buds and decreasing amount of nitrogen in the culture medium (either in its ammonium or nitrate form) leads to 50%-decrease in the number of buds induced per explant. Previous reports mentioned that macronutrients have the most significant effect on bud formation of peach hybrid rootstock GF677. In addition, high amount of nitrogen is necessary to achieve the highest height of pyrodwarfin vitro plantlets. In contrast to the basal media, neither bud formation nor height of plantlets did not affected by the type of auxins, IAA and IBA. Also weight of plantlets was similar in all treatments and shows the effect of basal media and auxins were not significant on biomass production. According to the results of rooting experiment, plantlets that were cultured in MS and DKW had higher height than QL and Knop in rooting phase. Also, 1/2 MS-cultured plantlets have the lowest height among all treatments. These results showed that macronutrients have positive effects on the growth of pyrodwarf plantlets as decreasing concentration; the growth of plantlets was inhibited. In contrast to shoot growth, number of roots per explants in 1/2 MS medium was significantly higher than the other media. These results are expected as shoots and roots of plants have different response to environmental stimuli. Data obtained from the following experiment of rooting indicated that IAA improved root induction similar toother functional traits of plants but the presence of both of those compounds in medium have inhibitory effect on the functional traits of plants. These data suggest that macronutrients and hormonal compounds have impressive impact on the regeneration of pyrodwarf plantlets. In this regard, MS medium supplemented with 0.5 mg.L-1 BA and 0.05 mg.L-1 IAA or IBA induced most number of buds and the regenerated plantlets hadthe highest height in that medium compared to the other treatments. Also, 1/2 MS medium containing 1 mg.L-1 IAA was identified as the best media in case of rooting parameters.

Breeding and production of new varieties of ornamental plants as well as their propagation and developing are an expanding industry. Researches find it necessary to increase the genetic variation in Lilium, because of value of this ornamental plant as the fourth cut flower in the world. The present study was carried out to investigate gamma radiation effects on in vitro mutation induction in Lilium. ISSR markers were used to determine genetic variation in resulting explants. Thin cell layer (TCL) explants were treated with 2, 6 and 10 Gy of gamma rays. Treated explants were cultured in MS medium supplemented with 1 mg/l BA and 0.5 mg/l NAA. Results showed all treatments induced genetic diversity, but the optimal dose was 2 Gy, because of increase diversity and survival rate of explants. The results confirmed the efficiency of ISSR markers for detection of genetic variations. Furthermore, the results suggested that mutatants induced by gamma irradiation are not only as a source for genetic variations but also as a useful tool for early selection of desirable mutants by breeders.