جستجوی مقالات مرتبط با کلیدواژه « کشت درون شیشه ای » در نشریات گروه « کشاورزی »

Conservation of potato germplasm (Solanum tuberosum L.) is of great importance due to its role in providing food security. Considering high heterozygosis of potato and severe segregation in the progeny obtained from sexual reproduction, it is necessary to use asexual propagation to maintain selected genotypes. Although in vitro culture is an efficient method for maintaining potato genotypes, rapid growth of plants under optimum growth conditions, makes multiple subcultures necessary to be done. The later leads to increased costs and an increase in the probability of somaclonal variation. Therefore, it seems to be necessary to induce slow growth in plants maintained under in vitro conditions. In the current research the aim was to find out the best in vitro treatment for reducing the growth of potato shoots with the least negative effect on them. To approach the aim, two types of agar (including agar-agar and confectionery agar) and two osmotic agents (including sorbitol and mannitol) were evaluated on three potato genotypes in 6℃. The traits of shoot length, number of possible buds and microplant condition were recorded after 9 months. The results of data analysis showed that in all the three investigated genotypes, sorbitol osmotic agent (in combination with agar-agar or confectionery agar) at the temperature of 6 ℃ was the best treatment for medium-term storage of potato germplasm. It was mainly due to having the least shoot length, good microplant condition and also having enough buds for subsequent subcultures.

 Lily, a member of the genus Lilium, belonging to the Liliaceae family is one of the most important commercial pot and cut flower species and one of the three major bulb crops in the commercial market because of its large, colorful and fascinating flowers. Lily hybrids are the most economically important plants with varied flowers. Hybrid Eastern lily (Lilium oriental hybrid ‘Casablanca’) is a perennial bulbous plant that its propagation by bulb in natural condition is time-consuming, so produces 1–2 bulblets per bulb scale in one years’ time which is not sufficient for large scale cultivation of this plant. One of the most important and best methods for vegetative propagation and breeding of lilies is in vitro bulb scale culture. In vitro adventitious bud regeneration from scales of Lilium rely on many factors like cytokinin and auxin concentrations such as BA and NAA. The successful use of tissue culture techniques for rapid propagation of some species of the genus Lilium including L. ledebourii, L. orientalis, L. longiflorum, L. japonicum, L. speciosum, L. concolor, L. nepalense, L. regale, L. oriental hybrid, L. Asiatic hybrid has been reported. The purpose of the current study was to evaluate the effect of different concentrations of BA and NAA on in vitro proliferation of Lilium oriental hybrid ‘Casablanca’ using bulb scale as explant to establish a suitable protocol.
 Effect of various concentrations of 6-benzyle adenine (BA; 0, 0.5, 1 and 2 mg l–1) and ɑ-naphtaleneacetic acid (NAA; 0, 0.1, 0.2 and 0.4 mg l–1) were evaluated on in vitro proliferation of L. ‘Oriental’. Bulb scale as explant and MS basal medium as culture medium were used. Activated charcoal was applied to inhibit the browning of the culture medium and explant. The experiments were conducted in completely randomized design (CRD). The 16 treatments were applied, each treatment had 4 replications and each replication had 4 individuals. Therefore, in these experiments, a total of 192 bulbs were used. Traits including total plantlets fresh weight, leaf length, leaf number, bulblet weight, bulblet diameter, bulblet number, survival percentage, root length and root number related to in vitro proliferation were measured. All the statistical analyses were done by using SAS and Tukey’s test. Arcsin software was used for changing percent data.
 The interaction effect of BA and NAA was significant for all measured traits. Results showed that the maximum number of bulblet (8.66) and root (5.36) were obtained in culture medium enriched with 0.5 mg l–1 BA together with 0.4 mg l–1 NAA. Culture media supplemented with 0.5 mg l–1 BA together with 0.2 mg l–1 NAA and 1 mg l–1 BA together with 0.1 mg l–1 NAA with induction of 7.33 bulblets per explant were suitable media. The largest number of leaf (4.33) was measured in culture medium containing 1 mg l–1 BA together with 0.1 mg l–1 NAA. The highest bulblet weight was measured in culture medium supplemented with 1 mg l–1 BA along with 0.2 mg l–1 NAA. The greatest survival rate (100%) was observed in medium enriched with 0.5 mg l–1 BA together with 0.1 mg l–1 NAA. Survival rate (90%) in explants treated with 2 mg l–1 BA along with 0.4 mg l–1 NAA was high. Obtained results revealed that the presence of both BA and NAA in culture media for enhancement of most traits is necessary and critical. Plantlets were transferred to a growing medium containing cocopeat, peat moss and perlite in identical proportion for acclimatization following proliferation. Approximately, 90% of regenerated plantlets survived and were morphologically similar to the mother stocks. This study will help the producers and breeders for commercial and improvement purposes. The effective role of the simultaneous presence of both auxin and cytokinin in the culture medium in effective organogenesis was shown in the present study. Similar findings were reported for some lilies such as L. ledebourii (Baker) Bioss., L. longiflorum and L. regale. Auxin was effective in stimulating bulb production and growth of the aerial part of the eastern lily, and its presence along with cytokinin is essential for leaf induction. Some studies have reported similar results. The type and optimal concentration of plant growth regulators (PGRs) in the culture medium for suitable in vitro propagation varies in different species. Genetic variations (species type), differences in the amount of endogenous production of PGRs and their interaction with each other are among some reasons for this difference. The proper ratio of auxin and cytokinin in the culture medium is effective for inducing cell division, cell differentiation, organogenesis and finally for achieving a complete plant. Root production with appropriate quantity and quality leads to the suitable survival of seedlings resulting from the growth of cultured explants under in vitro conditions and adapted plants. Current study showed that the presence of both BA and NAA is better than the presence of one of these two PGRs for induction and growth of root. Some similar findings were reported, however in most studies, the presence of auxin as individual PGR has been found to be more suitable for root induction.

Ferulago (Ferulago ssp.) medicinal plant belongs to Apiaceae family and is endemic of Iran. Species of this genus are extremely endangered, considering the seed dormancy, excess harvesting and environmental stresses such as drought. By considering this plant as a valuable medicinal-rangeland plant, its production and reclamation is an essential task. This investigation was done to optimize micropropagation of two endemic species of Ferulago, included F. angulate and F. subvelutina. Maximum percentage of callus induction in F. angulata specie was reached as 100%, using rootlet explant (under treatments of 0 BAP + 1 NAA, 0 BAP + 1.5 NAA and 0 BAP + 2 NAA mg/l) and also true leaf explants (under treatments of 0.5 BAP + 0.5 NAA and 1 BAP + 2 NAA mg/l), and in F. subvelutina specie using true leaf explants (under treatments of 0.5 BAP + 0.5 NAA and 1 BAP + 2 NAA mg/l) respectively as 72.33 and 71.66%. The combined application of the cytokinin and auxin phytohormones has been shown to be effective in regenerating Ferulago species; so that the maximum regeneration was reached as 53.33 and 46.66% in F. angulata respectively under treatments of 0.5 BAP + 0.2 NAA mg/l and 0.5 BAP + 0.4 NAA mg/l and so on as 53.33 and 60 percent in F. subvelutina respectively under treatments of 1 BAP + 0.2 NAA mg/l and 1 BAP + 0.4 NAA mg/l. The best rooting treatment in both species was selected as the ½ MS cultural medium included 0.5 mg/l IBA. The adaptation stage was done in a mixture of soil, peat soil and sand with a weight ratio of 1: 1: 1, in which the total of 80% of regenerated plants from tissue culture, were successfully adapted to the outside environment.

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.

Orchis muscula L. is one of the worthwhile ornamental, medicinal, native and endangered species in Iran. In this research, plant tissue culture method has been used to propagate this valuable plant. For in vitro organogenesis, protocorm explants were surface sterilized and then cultured on different shoot and root induction media based on OrchiMax (OM) medium, supplemented with plant growth regulators with different concentrations alone or in combination. Based on results, the most shoot induction (100%) was obtained from protocorm explants cultured on medium containing 2 mg L-1 BAP and 0.5 mg L-1 NAA and the highest root induction (80%) was belonged to the treatment of IAA at 1 mgL-1.

This study aimed to evaluate the effect of different types and concentrations of plant growth regulators in MS medium on callus formation and regeneration of different explants of medicinal plant Galega officinalis. To callus induction, leaf, root, hypocotyl, and stem nodes explants were cultured on MS medium containing different concentrations of 2,4-D (0.5, 1, 3, and 5 mg/l) in combination with BAP (0, 0.5, 1 and 3 mg/l) or Kin (0, 0.5, 1, and 3 mg/l). It was observed that 2,4-D in combination with Kin was very effective and in most of the used concentrations, it resulted in 100% callus induction. Among them the 5:0.5 mg/l concentration of 2,4-D:Kin in the nodal stem explant showed the highest callus growth with an average of 1450 mg fresh callus weight. In order to direct regeneration, leaf, cotyledon, and stem nodes were cultured in MS medium containing different concentrations of BAP and Kin in combination with NAA, while regeneration was observed only in the stem nodes. The highest regeneration rate was related to 0.25:0.1 mg/l in both BAP: NAA and Kin:NAA with an average of 93.33%. The highest amount of induced shoots (with an average of 2.86 shoots in each explant) and the highest shoot length (5.6 cm) were observed at 2:0.5 and 2:0.1 mg/l of BAP:NAA, respectively. The shoots obtained from the regeneration experiment were transferred to MS medium containing different levels of NAA and IAA for rooting. The results of mean comparisons showed that 0.25 or 0.5 mg/l of NAA or IAA resulted in the highest percentage of rooting with an average of about 90%. The highest number of roots was related to explants cultured in 0.25 mg/l of both NAA and IAA growth regulators (with an average of 4 roots per explant) and also, the highest root length was observed in explants cultured in 0.25 mg/l of IAA (with an average of 6.5 cm). At all, in this study, the most appropriate combination of plant growth regulators and explant for callus induction and direct regeneration of G. officinalis was introduced, which can be useful in future biotechnological studies of this medicinal plant.

The present study was conducted to reduce the effects of salinity stress on germination and initial growth stages of Thymus vulgaris as a medicinal plant using brassinosteroid (BR) under in vitro culture. Thyme seeds were exposed to different concentrations of salinity (0, 50, 100 and 200 mM) and BR (0.5, 1 and 3 µM), and then different germination and growth indices as well as some phytochemical properties of seedlings were measured. Results indicated that under salinity conditions, the highest germination percentage (95%) was observed at the lowest salt concentration (50 mM) and the highest BR concentration (3 µM). Applying differentBR concentrations improved root and shoot height.It also increased dry and fresh biomass of thyme seedlings in a way that at the same salinity conditions of 200 mM, root and stem length increased about 30.5% and 42.9%, respectively, in samples treated with 3 µM BR in coparison with the ones treated with 0.5 µM BR. The amount of proline and antioxidant enzymes, peroxidase (POD) and superoxide dismutase (SOD) significantly increased in the seedlings treated with the highest BR concentration in comparison with those treated with the lower concentrations, and the seedlings had lower membrane permeability (lipid peroxidation). The results of correlation coefficient showed that there was a negative correlation between cell membrane permeability (amount of malondialdehyde) and all measured biochemical and morphological traits related to seedling growth. According to the results of this study, it is suggested to apply BR during the sensitive stage of seed germination and early growth of garden thyme seedlings under water or soil salinity conditions.

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.

The extinction threatens some native orchids which has economic value. Artificial seed technology can prevent the extinction of these plants and can be suitable for producing and exporting of product. In this study, protocorms of Dactylorhiza umbrosa were encapsulated. The effects of three temperature treatments 4, 20, and 25°C were investigated during three periods 30, 60, and 90-days of artificial seed storage. Percentage of artificial seed germination during storage conditions, after storage, total percentage of germination and number of days required for germination incidence, were investigated. The highest germination percent during storage conditions was related to 90-days storage at 4 and 25 ° C, and the lowest obtained after 30 days at 4 ° C, which did not show any germination. The highest germination percentage of artificial seeds after storage and cultivation was observed in 60 days stored seeds at 4 °C. The highest total percentage of germination was obtained after 60 and 90 days storage at 20 and 4 °C, respectively. The highest number of days befor germination incidence was observed after 60 days of storage. The best treatment for storage of artificial seeds was 4 °C for 30 and 60 days, which showed the lowest percentage of germination during storage conditions and the highest percentage of germination after culturing.

The walnut family (Juglandaceae) consists of approximately 60 species of deciduous trees is native of the American continents, Europe, and Asia. Pecan (Carya illinoensis) is belonged to the Juglandaceae family and is one of the most valuable nut products all over the world. Embryo culture techniques for plant breeding as well as basic studies in physiology and biochemistry are widely used. The low percentage of germination and the long propagation cycle and the need for stratification treatments from three to six months are the most important barriers to the development of high yielding cultivars through hybridization. Plant regeneration methods from embryo culture in vitro allows overcoming the barriers of hybridization, as well as obtaining higher and faster multiplication rate of plants of an elite genotype.

In this experiment, an adapted native genotype of pecan in Gorgan city, Golestan province, Iran was selected. The mature fruits were harvested after five months of pollination. They were immediately transferred to the laboratory. For cold pretreatment, nuts packed in a paper bag and stored in 4-5ºC for 15 days. The effect of two types of culture medium, growth regulators and seed pretreatment (15 days at 4-5 °C) on germination of mature embryos of pecan has been determined. Murashige and Skoog (MS) and Woody Plant Medium (WPM) and IBA (0 and 1 mgl-1), BAP (0, 1 and 2 mgl-1) and GA3 (0 and 1 mgl-1) media were used to embryo rescue evaluation. The data obtained were statistically analyzed in completely randomized block design (RCBD). Each treatment was replicated at least third, and each replicate consisted of two zygotic embryos. Means of germination period, percent of seed germination, root and shoot length and leaf number in different media and various PGRs combination were compared based on LSD at p ≤0.05.

The results showed, although cold pretreatment for 15 days had no effect on germination period, root length and number of leave but also, effect on germination percentage and shoot length. There are some different hypothesis about the effect of cold pretreatment on embryo germination between researchers. Some researchers believed that, there is low efficiency in embryo germination in lack of cold pretreatment and GA3. Cold pretreatment or GA3 reduce the ABA level and promote embryos germination. The others reported poor germination for somatic embryos when they treated with GA3 and cold pretreatments. Pearce et al. (1987) reported that GA3 and substrate of GA3 can be increased during the chilling process as ABA levels decrease. Furthermore, application of exogenous GA3 induces germination. Tang et al. (2000) reported that somatic embryos germination poorly happened in cold condition and addition of GA3 did not change the poor germination. Kaur et al. (2006) and Peyghamzadeh and Kazemitabar (2010), reported that the embryo germination in Juglans regia L. was higher when GA3 and cold pretreatments were simultaneously applied as compared to those when applied separately. In this experiment, media has no effect on embryo germination period but, could effect on other parameters. As the results showed, MS media showed the maximum percentage of germination, root and shoot length and number of leave in both condition (with and without cold pretreatment). In this experiment root length of germinated pecan embryo was higher in MS medium. Mapelli et al. (2001) reported that seed germination resulted in marked changes in the metabolism of free amino acids in walnut cotyledons. About 52% of the total free amino acids in one-month-old seedlings was present in the cotyledons and about 26% was in the taproot. The concentration of free amino acids in the taproot was similar to that in the embryonic axis, and greater than that in the cotyledons. T11 (1mg/l-1 IBA, 1mg/l-1BAP and 1mg/l-1 GA3) and T12 (1mg/l-1 IBA, 2mg/l-1BAP and 1mg/l-1 GA3) treatments were the highest in germination percentages in both treatment (with and without cold pretreatment). There was no significant differences between 1 mgl-1 and 2 mgl-1 of BAP.

Pecan as like walnut, is considered to be one of the most recalcitrant species in vitro. It is necessary to determine the optimal culture conditions to establish it for shortening time in seed propagation. This seedling could be applied as primary material for breeding programs, grafting and physiology study. The best growth of micro plant achieved in MS medium with 1 mgl-1IBA, 1 mgl-1GA3 and 2 mgl-1BAP.

Papavear fugax Poir. from Meconidium section of Papaver is an important source for alkaloids. Given the presence of thebain, morphine and codeine in this plant, biotechnological studies, especially In vitro culture of this plant would be of importance. In this study, callus induction and In vitro regeneration of this species from leaf explants in MS medium containing different levels of naphthalene acetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-D), Kinetin (Kin) and Benzyl adenine purine (BAP) was investigated at 25 °C and 16 h light and 8 h darkness  based on a completely randomized design with three replications. Analysis of variance showed that for callus induction rate and callus weight, there were significant (p<0.01) differences between different culture media. Based on results, the proper medium for callus induction of leaf explants was MS medium supplemented with 1 mg/l NAA and 1 or 0.5 mg/l BAP. The highest callus fresh weight was obtained in MS medium supplemented with 1 mg/l NAA and 1 mg/l BAP. In vitro regeneration of this species from leaf explants was also investigated in MS medium containing different levels of NAA, Kin and BAP and the best medium for regeneration was MS medium supplemented with 1 mg/l Kin and 1 mg/l NAA. By inspecting rooting of seedlings in MS medium containing different levels of indole acetic acid (IAA) plus Kin or BAP, the highest rooting percentage was obtained in MS medium containing 1 mg/l of each of IAA and Kin.

Epipactis veratrifolia is a terrestrialorchid that belongs to thetemperate zones of Iran with great breeding potentials for ornamental usages. Although in vitro propagation of this orchid has been previously performedbut investigation on factors influencing its in-vitro growth and photosynthesis is still needed. In the current study, three-leaflet seedlings were cultured in closed vessels containing modified Fast liquid medium together with sterilized perlite (for sample establishment). To remove CO2, vials containing saturated KOH solution as CO2 absorbent and to increase CO2 concentrations, vials containing 3 mL CO2-releasing solutions (3 M sodium bicarbonate and sodium carbonate) were placed into the culture vessels. The experiment was carried out based on a completely randomized design with three replications and three samples per each replicate. Growth parameters including fresh and dry weights of shoot, stem height and root length together with transpiration rate and maximum quantum yield of photosystem II efficiency (QYmax) of the samples were measured. The highest values for shoot height, shoot dry and fresh weights and root length were observed in CO2-increased treatments. Removing CO2 from the atmosphere of culture vessels caused a dramatic decrease in QYmax of plantlets in vitro. Meanwhile, following desiccation, higher transpiration rate was detected in control and CO2-increased treatments, while removing CO2 decelerate transpiration rate of the plantlets. In conclusion, with increasing CO2 in vitro we can promote photosynthetic efficiency of Epipactis veratrifolia and as a result enhance growth of plantlets in vitro.

This research was conducted in two stages to optimize in vitro propagation of Persian wild paeony. Stage 1: effect of BAP (0, 0.5, 1 and 2 mg.l-1), NAA (0, 0.1, 0.2 and 0.3 mg.l-1) and GA3 (0 and 0.5 mg.l-1) on apical bud ofPaeonia mascula and stage 2: effect of BAP (0, 0.5, 1 and 2 mg.l-1) and NAA (0, 0.25, 0.5 and 1 mg.l-1) were studied on embryonic callus induction on young leaves of Paonia mascula. At stage 1: the highest shoots number (5.38) was obtained on media containing 1 mg.l-1 BAP + 0.1 mg.l-1 NAA+ 0.5 mg.l-1 GA3. The results showed that increasing BAP level caused decreasing of shoot length. At stage 2: maximum of compact embryonic callus (17.93%) and somatic embryo number per explant (7.11) were obtained on 2 mg.l-1 BAP and 0.5mg.l-1 NAA. For callus proliferation, calli were maintained on MS medium containing 2 mg.l-1 BAP, 0.1 mg.l-1 NAA and 0.5 mg.l-1 GA3. Maximum rooting percentage (70.51%) and root number (0.0.02) were obtained with 0.25 mg.l-1 NAA.

Potato (Solanum tuberosum) is an important crop in tropical countries. Salinity stress is the crucial factor that seriously limits agricultural production in various regions especially in arid and semi-arid areas. Salicylic acid is a bioactive molecule that synthesizes via enzymatic and non-enzymatic pathways under stress conditions in different organs of plant, regulates and adjustments defense reactions of plant. Salicylic acid (SA) is known as a signalling molecule that modifies plant responses to pathogen infection. Many studies have shown that this compound can protect plant under oxidative stresses and maintain chlorophyll. In addition to being an important component of biotic stress tolerance mechanism, SA also regulates various aspects of plant responses to abiotic stresses through extensive signalling cross-talk with other growth hormones. However, exact mechanisms by which SA protects plants during abiotic stresses remain obscure. Salinity stress is the crucial factor that seriously limits agricultural production in various regions especially in arid and semi-arid areas. Salicylic acid is a bioactive molecule that synthesizes via enzymatic and non-enzymatic pathways under stress conditions in different organs of plant, regulates and adjustments defense reactions of plant. Salicylic acid (SA) is known as a signalling molecule that modifies plant responses to pathogen infection. Many studies have shown that this compound can protect plant under oxidative stresses and maintain chlorophyll. In addition to being an important component of biotic stress tolerance mechanism, SA also regulates various aspects of plant responses to abiotic stresses through extensive signalling cross-talk with other growth hormones. However, exact mechanisms by which SA protects plants during abiotic stresses remain obscure.

This experiment was conducted at the plant tissue culture laboratory of Horticultural Sciences, Department, University of Tabriz, Iran, during spring–summer of 2017. The present study was aimed to investigate of salicylic acid effect on betaine aldehyde dehydrogenase gene expression and glycine betainesynthesis in Solanum tuberosum cv. Agria under salinity stress on in vitro condition. The experiment treatments included four level of salycilic acid (0, 1, 10 and 100 mM) and two level of sodium chloride (0 and 70 mM). In the present study, MS media culture was used and sodium nitroprusside was applied for increasing the betaine aldehyde dehydrogenase gene expression (the responsible gene of glycine betaine synthesis) under salinity stress. Four weeks after treatment, total RNA of treated explants was extracted and semi quantitative RT-PCR was used for the analysis of expression of betaine aldehyde dehydrogenase gene.

and semi quantitative RT-PCR was used for the analysis of expression of betaine aldehyde dehydrogenase gene. The glycinbetainecontent was measured with iodide potassium. The survey of betaine aldehyde dehydrogenase gene expression showed increased under salinity stress. Also salicylic acid increased the glycine betaine content in grown plantlets which were grown under normal condition.The expression pattern of glycine betain gene showed tha by increasing of salicylic acid and sodiuom chloride concentration the expression of glycine betain gene has been increased in all samples. however under salinity stress this compound showed negative effect on glycinbetaine content.

In conclusion, antioxidant activity, total phenol and protein were increased salinity stress. In addition, antioxidant activity and glycine betaine content during salt stress period was decreased application of nitric oxide. The glycine betaine content of plantlets in general condition with application of sodium Salicylic acid increased but under salinity stress, Salicylic acid had negative effect on glycine betaine content. The results of this research showed that exogenous application of salicylic acid increased the expression level of genes and lead to enhancement of plant tolerance to salinity stress. Further studies are necessary to determine optimum concentration and duration of Salicylic acid application in order to achieve maximum benefit in Solanum tuberosum tissue culture.

Introduction :

The use of invitro hydroponic culture is one of the useful and practical methods for selection of superior isolates of plant growth promoting rhizobacteria with high colonization potential at root surface. In this regard, the present study was designed to select superior isolates isolated from dry-land farming of Qazvin and Zanjan provinces during the previous stages of this investigation.

Materials and Methods:

 This experiment was carried out based on a completely randomized design (CRD), including: inoculation of wheat seeds with 16 bacterial isolates and culture of seedlings in Hoagland nutrient solution (EC 8 dS/m and osmotic potential (OP) -0.54 MPa) containing tricalcium phosphate (source of low-soluble phosphorus), as well as non-inoculated seedlings was cultured in Hoagland nutrient solutions containing monopotassium phosphate (control with source of soluble phosphorus) and tricalcium phosphate (control with source of low-soluble phosphorus) at three replications in growth chamber for 45 days. The length of the light (with 196 μmol photons m−2 s-1 light intensity) and dark period in these times was 16 and 8 h, respectively, The day and night temperature were 25±2 and 20±2 °C, respectively. At end of experiment (45 days after transportation of seedlings into invitro hydroponic culture) shoots and roots of plants were harvested separately; then, Population of phosphate solubilizing bacteria (PSB) on root surface, pH and concentration of available phosphorus in nutrient solution, fresh weight, dry weight and length of both section of plants, P-concentration and P-uptake of plant, and relative water content (RWC) of leaf were measured. Ultimately, correlation (Pearson) among measured traits were calculated.

Results and Discussion:

 Results showed that inoculated wheat seedlings with B18 isolate perished. It seems that B18 isolate was either a highly pathogenic plant or its metabolites were highly inhibitory to the seedling which in short time killed the wheat seedling. Except B (14, 17, and 32) isolates; the rest of isolates had over 6×106 CFU/g root fresh weight. All bacterial isolates compared to the control with source of insoluble phosphorus, increased available phosphorus and decreased pH of nutrient solution. Dissolution of inorganic phosphates by PSB with chelating processes, secretion of inorganic and organic acids has been proven topic. Thus, reducing pH and increasing soluble phosphorus in nutrient solution at PSB treatments are reasonable. B (1, 2, 3, 4, 5, 6, 14, 17, 32) isolates treatments compared to control with tricalcium phosphate, increased RWC of leaf, and also increased length, fresh weight and dry weight of root and shoot of wheat plants. Previous research has shown that inoculation of plants with PGPR under drought and salinity conditions improved RWC of plant leaves and plant growth indices; Of course, result of some experiment show that some of PGPR do not always improve plant growth under all conditions. There was a significant positive correlation among P-uptake, RWC, root length, shoot height, fresh and dry weight of root and shoot of wheat plant. Also, the pH of nutrient solution had a positive correlation with root length, but it had a negative and significant correlation with P-concentration of nutrient solution and P-concentration of plant. PSB population at root surface had a negative correlation with pH of nutrient solution and root length of plant, but with P-concentration of nutrient solution had positive and significant correlation.

Conclusion:

 All of screened and selected PSB isolates in lab (in respect of PGP traits) could not promote plant growth; even some of these isolates (such as B15 and B18) had negative effects on wheat growth indices. Inoculation of wheat with PSB isolates significantly increased the use of insoluble phosphorus. Solubility of tricalcium phosphate by isolates and increased phosphorus availability cannot lonely improve wheat growth indices; it seems that the outcome of the set of PGP effects of these bacteria and the secretion of their metabolites in the presence of plant root are determinative agents for improvement of wheat growth indices. Generally, B (1, 2, 3, 4, 5, 6, and 32) isolates were superior isolates in respect of colonization at root surface, relative water content (RWC) and growth indices of wheat plant; and these isolates are recommended for further experiments in greenhouse and field (in order to production of suitable biofertilizer for dry-land farming of wheat).

Cornelian cherry (Cornus mas L.) is one of the Cornus species members belonging to Cornacea family. It is one of the native shrubs of the central and north-western parts of the Alborz Mountains in Iran. This study was conducted with the aim of establishment and proliferation of Cornelian cherry shoots with under invitro culture of lateral buds. For this purpose, two types of WPM and QL mediums and four levels of benzyl adenin (BA) (0, 0.5, 1 and 2 mg/L) with constant concentration of 0.5 mg/L of IAA for all replicates were used in a factorial experiment base on a completely randomized design with 5 replications. The highest proliferation indices, including number of shoots (4.79 for each sample), shoots length (1.41 cm) and number of nodes (32.5 for Each sample) was recorded at a concentration of 1 mg/L BA in QL medium. Also, the results of correlations between traits showed that all traits were positively and significantly correlated at p≤5% level. Considering the proliferation factors, the results showed a significant difference with the control group, and the positive and significant effect of benzyladenine and QL medium on the proliferation of cornelian cherry shoots is reported.

Among species of hardwood forest trees, Eucalyptus citriodora is a fast growing plant that is cultivated for aromatic essential oils in perfumes, pharmaceuticals, and its soft and light wood in the paper and furniture industry. The micropropagation of E. citriodora Lemon-scented Gum was carried out in two medium culture of MS (1/2N) and WPM through bud culture. Sterilization was done using solutions of mercuric chloride 0.1% and sodium hypochlorite 20%. Shoot multiplication was done with cytokinin (BAP, Kin), auxin (IBA) and gibberellin (GA3) hormones and rooting with auxin hormones IBA, NAA and IAA in only MS (1/2N) medium. The shoot multiplication was assessed in two medium using factorial experiment based on the completely randomized design (CRD) and rooting multiplication in one medium using CRD. Propagation coefficient, shoot length, greenity, total root and rooted seedlings were measured. The best sterilization was immersion seeds in 20 % sodium hypoclorite solution in 18 min. The best propagation and shoot elongation was obtained in MS (1/2N) medium coupled with BAP, Kin, GA3 cytokinin hormones and auxin hormones IBA in 0.3, 0.2, 0.1, 0.01 mgl-1 and 0.3, 0, 0.1, 0.01 mgl-1concentrations respectively by 200 mgl-1 P.V.P. The best rooting treatments were a modified MS (1/2N) medium, auxin hormone NAA and IBA+IAA in 1 mgl-1, 0.5mgl-1. These plantlets transferred to soil and were kept in the greenhouse conditions. The results of this study show that tissue culture is a suitable method for the propagation of this valuable species in a short time.