Breeding and Biotechnology of Plant and Flower
Marzieh Ghorbani; Khosro Parvizi; Mohammad Yazdandoost Hamedani; Darab Hassani
Abstract
Introduction
In our country, walnut tree propagation is traditionally done through seed cultivation, often resulting in seed rot and death due to fungal, bacterial, and viral contamination (MC Granahan et al., 1986; Driver & Kenyuki, 1984; Saadat & Henry, 2002). The traditional method, in addition ...
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Introduction
In our country, walnut tree propagation is traditionally done through seed cultivation, often resulting in seed rot and death due to fungal, bacterial, and viral contamination (MC Granahan et al., 1986; Driver & Kenyuki, 1984; Saadat & Henry, 2002). The traditional method, in addition to low multiplication rates, leads to high variation in resulting seedlings, potential loss of seedlings due to contamination, and reduced efficiency in subsequent stages (Unit, 2012; Kaur et al., 2006). Previous research has mainly utilized concentrations of one milligram per liter of benzyl adenine along with small amounts of indole butyric acid for Iranian walnut growth and enrichment (Rodrigues, 1982; Revilla et al., 1989; Penuela, 1988; Mejzadeh et al., 2010, 1997; Amiri & Qaraati, 2012; Riosleal et al., 2012). This research aims to build upon and optimize previous work, evaluating the effectiveness of different concentrations of two growth regulators, benzyl aminopurine and adenine sulfate, on walnut plantlet regeneration and growth traits in tissue culture.
Materials and Methods
This study was conducted to optimize the tissue culture protocol for the "Chandler" cultivar walnut and determine the most suitable culture medium and hormonal composition for micropropagation. Lateral and terminal buds from the current season's branches were sterilized and cultured in DKW medium containing 2 mg/liter of benzyl adenine hormone and 100 mg/liter of indole butyric acid hormone, with polyvinyl pyrrolidine at one g/liter and activated charcoal at 2 g. Two-factorial experiments were used to process and multiply the plant after the establishment phase. The first factor was DKW culture medium containing five levels of adenine sulfate (0, 20, 40, 60, and 80 mg/liter), and the second factor was benzylaminopurine plant growth regulator with five hormonal levels containing 0, 0.5, 1, 1.5, and 2 mg/liter in combination with 0.01 mg/liter of indole butyric acid hormone. DKW base culture medium without any plant growth regulating substances was considered as control. After two months, growth traits including plantlet weight, stem length, number of leaves, number of buds, and number of leaflets per plantlet were measured in different culture media. The resulting data were statistically analyzed using SAS 9.1 software, and means were compared using Duncan's multiple range test with a five percent probability level.
Results and Discussion
The analysis of variance showed that both plant growth regulators, benzyl aminopurine and adenine sulfate, had a very significant effect at 1% probability level on plantlet weight, stem length, number of leaves, number of buds, and number of leaflets. The interaction effect of benzyl aminopurine with adenine sulfate treatment on plantlet weight and stem length was significant at the 1% probability level. However, the interaction effect of benzyl aminopurine with adenine sulfate treatment on the number of leaves, number of buds, and number of leaflets was not significant. The results indicated that an increase in the levels of growth regulators benzyl aminopurine and adenine sulfate led to an increase in plantlet weight. The positive effects of increasing the levels of growth regulating substances in increasing plantlet weight are likely due to their direct effect on nutrient absorption, utilization, and the photosynthesis process. These results align with the research of Hatemzadeh et al. (2017) and Saadat and Henrati (2002). The positive effects of higher concentrations of both growth regulators on the increase in the number of sprouts and the lack of significant difference between the two high concentrations confirm that the use of high levels does not exceed the economic threshold. It can be justified that in excessive and unconventional concentrations, positive effectiveness is not achieved, but it can also impose more costs on the walnut tissue culture program. The appropriate concentration of BAP and adenine sulfate increases the leaf surface through the effect on cell divisions, resulting in receiving more light radiation and increasing the rate of photosynthesis. It seems that the two growth regulating substances in the appropriate concentration intensified each other's effect, affecting the rate of absorption and utilization of materials from photosynthesis, leading to an increase in the fresh and dry weight of the seedling. This, in turn, leads to a decrease in the length of the reproduction period in the resulting seedlings and an increase in the efficiency of the seedling production in walnut tissue culture.
Conclusion
The use of both studied growth regulators significantly increased plantlet weight, stem length, number of leaves, number of buds, and number of leaflets compared to the control treatment. Plantlet growth was achieved with the use of plant growth regulators, whereas no growth was observed in their absence. All assessed traits increased significantly with the addition of plant growth regulators, with the highest trait values obtained through the simultaneous use of benzylaminopurine and adenine sulfate.
Mina Ghazaeian; Gholamhossein Davarynejad; Kamal Ghasemi Bezdi; Seyyed Hossein Nemati
Abstract
Introduction: 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 ...
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Introduction: 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.
Materials and Methods: 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.
Results and Discussion: 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.
Conclusion: 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.
Masud Ghasemi; Hossein Arouiee; Pejman Azadi; Atoosa Ali Ahmadi
Abstract
Introduction: Greater celandine (Chelidonium sp) is one of the plants that its propagation through seed occurs slowly. In addition, Chelidonium majus L. has limited habitats in Iran. For this reason, micropropagation can be considered as an effective method for its rapid and massive propagation and conservation, ...
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Introduction: Greater celandine (Chelidonium sp) is one of the plants that its propagation through seed occurs slowly. In addition, Chelidonium majus L. has limited habitats in Iran. For this reason, micropropagation can be considered as an effective method for its rapid and massive propagation and conservation, which can lead to the production of highly uniform plants. Chelidonium majus L. also contains a large amount of secondary metabolites of Isoquinoline alkaloids, including Chelidonine, Sanguinarine, Captesin, Berberrine and Chloritrine, and phenolic compounds. Therefore, the aim of this study was to investigate micropropagation of Chelidonium majus L. and compare the total phenol content in leaf, stem and root in obtained plantlets.
Materials and Methods: To begin the experiment, seeds of Chelidonium majus L. were first washed with distilled water containing a few drops of tween20. Then they were washed with 70% alcohol for 1 min and were finally washed with double-distilled water. Next, they were disinfected with 1% sodium hypochlorite for 5 min, and again were rinsed with distilled water for 3 times of 5, 15, and 180 min under laminar air flow hood. The effects of TDZ at concentrations 0, 0.25, 0.5, 0.75 and 1 mg/L, BAP at concentrations 0, 0.5, 1, 1.5, 2 mg/L considered. Then, the effect of best treatment in combination with NAA and IBA at 0.25, 0.5, 0.75 and 1 mg/L on growth parameters (number of shoot, shoot length and shoot formation capacity index), were studied. The effect of IBA, NAA and IAA at 0, 0.5, 1, 1.5 and 2 mg/L on rooting parameters (number of root and root length) in MS medium supplemented with 3 g/L activated charcoal in in vitro conditions were evaluated. Then different ratios of cocopeat, perlite and peat moss were used for acclimatization of the obtaining plants. Folin method was used to measure total phenol content. The experiment was conducted as factorial in a completely randomized design with four replications.
Results: The results of analysis of variance for proliferation and rooting traits showed that there were significant differences among the treatments at 1% probability level. The results of means comparison showed that the highest numbers of shoots and shoot formation capacity index were obtained from the treatment of 0.5 mg/L TDZ with the average of 8.12, which did not show a significant difference from the concentration of 0.25 mg/L TDZ, and the lowest shoot number was related to the control treatment. Increasing the amount of TDZ hormone led to the reduction in shoot number, so that at concentration of 1 mg/L TDZ, the average shoot number per explant was four. Combination of 0.5 mg/L TDZ with IBA and NAA had lower effect on Chelidonium majus L. proliferation. Moreover, the greatest shoot length was observed in the treatment of 2 mg/L BAP. Comparison of means values showed no significant difference between the treatments of 2 and 1.5 mg/L BAP at 1% probability level. In this study, MS medium containing 1.5 mg/L IBA was the most appropriate treatment for root formation. The effect of NAA hormone on root number of Chelidonium majus L. showed that the highest number of root was obtained from the treatment of 2 mg/L NAA. Besides, the effect of IAA on root number of Chelidonium majus L. showed that the highest number of root was observed in the treatment of 1 mg/L IAA, and the lowest number of root was related to the control treatment .The results of means comparison for the percentage of acclimatized plants showed that the ratio of 0:2:1 had a significant difference from the rest of the culture media and 85% of the plants were acclimatized, while the ratio of 1:2:1 showed the lowest percentage of acclimatization (20%). Furthermore, the results showed that the culture media had significant effect on acclimatization stage at 1% probability level. The results of the analysis of variance for total phenol content in leaf, stem and root tissues showed that there were significant differences among these three tissues. The results showed that the amount of total phenol in leaf was higher than in the stem, and the amount of phenol in root was insignificant.
Conclusion: Based on the results of this study, micropropagation can be used as a method for commercial production of this species under in vitro conditions.
Maedeh Aghdaei; Seyyed Hossein Nemati; Leila Samiei; Ahmad Sharifi
Abstract
Introduction: Pepino (Solanum muricatum Aiton) is a diploid herbaceous plant belongs to the Solanaceae family, which is growing in subtropical zone, originates from Andes in South America. It is commercially grown for its fruit, which is appreciated not only for food but also for its appearance, in South ...
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Introduction: Pepino (Solanum muricatum Aiton) is a diploid herbaceous plant belongs to the Solanaceae family, which is growing in subtropical zone, originates from Andes in South America. It is commercially grown for its fruit, which is appreciated not only for food but also for its appearance, in South American countries, including Bolivia, Colombia, Ecuador and Peru, as well as in countries such as New Zealand and Australia. Pepino is propagated by seed, cutting, and tissue culture methods. Most pepino cultivars are sexually fertile and produce viable seeds, but their seeds have poor germination and high level of heterozygosis causing to highly variable plants. Both mentioned negative aspects have limited the mass production of this plant through seed. In this case, stem cutting is used as the most common way of propagating pepino led to transmission of viral diseases and increasing propagation costs as two main limiting factors of pepino propagation. So, micropropagation systems are a promising tool to produce disease-free clonal plant material with low costs. Therefore, the present study was aimed to assess the effect of different media and plant growth regulators on micropropagation traits of pepino.
Materials and Methods: Three separate experiments were carried out in institute of plant sciences of Ferdowsi University of Mashhad in 2016. Pepino seeds were bought from company of Plant World Seed, UK, were cultivated on MS medium. Grown plants were used as source of providing explants. Four mediums, including MS, ½ MS, SH and B5 were used to determine the best culture medium for shoot regeneration of pepino using single node explant. A factorial experiment was conducted based on a completely randomized design. Some growth properties such as number of shoots, shoot length, number of roots, root length, leaf number and leaf length were evaluated after two and four weeks. In proliferation experiment, MS medium was compared with MS supplemented with different concentrations of BA (0.5, 1 and 2 mg L-1) and Kin (0.5, 1 and 2 mg L-1) applied as combined treatments, and also BA used alone at concentrations of 2, 4 and 6 mg L-1 that was conducted based on a completely randomized design. For rooting of explants, an experiment was conducted based on a completely randomized design containing of two concentrations of IBA (at 0.3 and 0.6 mg L-1) and three concentrations of NAA (at 0.3, 0.6 and 0.9 mg L-1) in MS medium. Some growth properties including root number and length, root density and root quality were evaluated after four weeks
Results and Discussion: Results indicated that micropropagation rate of pepino was affected by culture medium type. The highest shoot length, number of root, root length and leaf number were obtained in MS medium, although statistically there was no significant difference between MS and ½ MS media. The highest number of shoots and leaf length were observed in MS medium, which led to a significant difference with other media (½ MS, SH and B5). Overall, Based on obtained results MS medium was the best culture medium for micropropagation of pepino using single node. In the proliferation experiment, the highest shoot and leaf number and plant color were obtained with using 2 mg L-1 BA + 1 mg L-1 Kin, whereas the highest shoot length and leaf length were observed in the 1 mg L-1 BA + 2 mg L-1 Kin and 1 mg L-1 BA+1 mg L-1 Kin treatments, respectively. Increasing in concentration of BA up to 2 mg L-1 in combination with Kin had a positive effect on shoot proliferation, while applying BA at concentration 2, 4 and 6 mg L-1 alone led to decrease in proliferation. Results obtained from rooting experiment showed that the highest root number, root density and root quality were obtained using IBA at the concentration of 0.6 mg L-1, whereas the highest root length was observed by applying IBA at concentration of 0.3 mg L-1, which led to a significant difference with other treatments. Furthermore, results indicated that the effect of IBA on rooting of pepino microshoots was more than NAA.
Conclusion: Generally, the best results were obtained by MS medium, 2 mg L-1 BA with 1 mg L-1 Kin for shoot proliferation, and IBA at concentration of 0.6 mg L-1 for the rooting of pepino nodal segments.
Seyyed Mohammad Hossein Hayatolgheibi; Ali Akbar Mozafari
Abstract
Introduction: The major problem in apple well-known rootstocks is lack of protocols for fast propagation under in vitro condition. Nitric oxide (NO) has been received the great encouragement and more attention in the recent years for its key signaling role. Nitric oxide plays a vital role in the growth ...
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Introduction: The major problem in apple well-known rootstocks is lack of protocols for fast propagation under in vitro condition. Nitric oxide (NO) has been received the great encouragement and more attention in the recent years for its key signaling role. Nitric oxide plays a vital role in the growth and development of plants, including stimulating the seed germination and seedlings growth as well as delaying in the senescence process.
In previous studies, the application of sodium nitroprusside (SNP), as NO-releasing agent, in combination with different plant hormones under in vitro conditions showed that, The application of 30 μM SNP significantly increased shoot multiplication (9.4 shoots per explant) and the use of 100 μM SNP induced rhizogenesis (2.1 roots per explants) of apple micro cutting. Accordingly, the current study attempted to investigate the effects of SNP treatments in combination with NAA and BA on the regeneration of adventitious shoots and in combination with IBA and NAA on rhizogenesis of micro cuttings in MM111 and MM106 apple rootstocks, , under in vitro conditions.
Materials and Methods: The current study was conducted to investigate the effects of SNP alone and in combination with different types of growth regulators (IBA, NAA and BA) on the morpho-physiological characteristics of Malling Merton 111 (MM111) and Malling Merton 106 (MM106) micro cuttings under in vitro conditions. MM111 and MM106 that growth under in vitro conditions were already used with about 2.5 cm length as the plant's sources. This research was carried out in the frame of two separate experiments (proliferation and rhizogenesis). For the proliferation, the MS medium supplemented with different concentrations of SNP (0.0, 2.96, 5.98, 8.94, 11.91 and 14.90 mg L-1) used as treatments. For the rhizogenesis, the ½ MS medium supplemented with different concentrations of SNP (0, 7.45, 14.90, 22/35 and 57.80 mg L-1) alone and combined with 1 mg L-1 IBA and 0.01 mg L-1 NAA was used. In the first experiment, characteristics such as shoot length, number of shoots, total soluble proteins and carbohydrates content, peroxidase activity, carotenoids, chlorophyll a, chlorophyll b as well as total chlorophyll content were measured. In the rhizogenesis experiment, root length, fresh and dry weight of roots, as desirable characteristics, were measured. In both experiments, the treatments were arranged in a completely randomized factorial design with four replicates. Four and three explants were used in each replication for proliferation and rhizogenesis experiments, respectively.
Results and Discussion: In the proliferation experiment, the number of shoots under 5.98 mg L-1 SNP was significantly higher than other treatments. The experimental treatments did not have a significant effect on the shoots length. Since nitric oxide may play a role in cell division, so it participates in the regeneration of the lateral branches and caused their proliferation (11). The results showed that total chlorophyll and carbohydrate contents in MM106 rootstock were significantly higher than MM111. The highest total chlorophyll content was observed in 5.98 and 14.90 mg L-1 SNP treatments and the maximum soluble carbohydrates was obtained in 2.96 mg L-1 SNP treatment. Shoot regeneration under SNP treatments had a relatively high correlation with the amount of soluble proteins and carbohydrates. In the rhizogenesis experiment, the root length at 5.98, 11.91 and 14.90 mg L-1 SNP treatments were significantly different from other treatments. The lowest root number was observed in the absence of SNP. The previous literature indicated that NO induces the CYCD3:1 gene and caused the expression of the anti-CDK inhibitor KPP2 gene at the onset of the formation of peripheral lateral root, and the genetic regulators of auxin-dependent cell cycle is directly related to NO. Also, our results showed that root fresh weight under 5.98 and 14.90 mg L-1 SNP treatments was significantly higher than other treatments, and the highest root dry weight was obtained in 5.98 mg L-1 SNP in comparison to other treatments. Based on the results it may be assumed that presence of SNP causes changes in the level of plant hormones at different stages of development, which is probably resulted in starting metabolic processes for root development and dry matter accumulation. Each trait showed a more favorable result at a specific concentration of SNP. However, proliferation under 5.96 mg L-1 SNP first increased then reduced.
Conclusion: Application of SNP treatments had a positive effect on the measured traits e.g. shoot numbers, total soluble protein and carbohydrate contents, as well as fresh and dry weight of roots. In this experiment, the concentration of 5.98 mg L-1 SNP had the highest effect in term of shoot numbers, total soluble protein and carbohydrate contents, compared to other treatments. The apple rootstock MM106 showed the better performance to the plant growth regulators than MM111 rootstock. Overall, the present results indicated that SNP material, as a NO-releasing source, can physiologically be present in the plant in a way that can induce regeneration of plants and this potential depends on the genotype type.
Ahmad Sharifi; Seyyedeh Mahdiyeh Kharrazi; Fatemeh Keykha Akhar; Abdolreza Bagheri; Elahe Samari; Maryam Moradiyan
Abstract
Introduction: Gerbera is one of the most important ornamental plants in the world. The importance of Gerbera is due to its beauty, diversity and economically aspects. Traditional propagation methods such as crown division and cutting methods are not suitable for obtaining disease free plants and rapid ...
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Introduction: Gerbera is one of the most important ornamental plants in the world. The importance of Gerbera is due to its beauty, diversity and economically aspects. Traditional propagation methods such as crown division and cutting methods are not suitable for obtaining disease free plants and rapid multiplication. These methods also do not have the capacity to fulfill global demands. Therefore, obtaining efficient protocol for micropropagation of this ornamental plant is necessary.
Materials and Methods: In this study the effect of various factors on in vitro regeneration, proliferation, rooting and acclimation of gerbera capitulum explants were analyzed in four separate experiments. Capitulum explants were first washed with running tap water for 30 min then surface sterilized by dipping in 1.5% sodium hypochlorite solution for 15 min and rinsed with sterile distilled water, followed by immersing in 0.1 % mercuric chloride solution for 10 min. To remove mercuric chloride residue, capitulum was rinsed with sterile distilled water. Subsequent washing was done with sterile distilled water for three times. Sterilization steps were done under laminar air flow hood. For regeneration, eight genotypes of gerbera capitulum explants (Famous, Sunway, Red Pearl, Pink Snow, Popov, Balance, Dune, Eagle)were cultured on solid MS medium containing several cytokynins, BA, TDZ, 2IP or KIN (4 mg/l) in combination with IAA (0.2 mg/l). In proliferation stage, the effect of different concentrations of BA was evaluated on proliferation rate of Sunway regenerated explants. In the rooting stage, Sunway genotype plantlets were cultured on ½ MS medium containing NAA, IBA or IAA (1 mg/l) or ½ MS medium without any hormones. The pH of the medium was adjusted to 5.7-5.8 prior to autoclaving (15 min at 121 oC and 1.5 kg.cm-2 pressure). The cultures were incubated in a growth chamber at 25±2 oC with a 16-h photoperiod (2500-3000 Lux) provided by cool-white fluorescent lamps. For acclimation of rooted plantlets, different substrates used as follow: 1- perlite, 2- perlite: Cocopeat, 3- Cocopeat: peat moss, 4- Cocopeat: peat moss; treated with fungicide.
After 30 days, the response of explants was evaluated for each experiment. Data preparation was done in the Excel program and data analysis was done using JMP-8 software. Mean comparison of the treatments was done by Tukey test and finally the charts were drawn using the Excel program.
Results and Discussion:The results of regeneration stage showed that application of MS media containing kinetin or 2IP did not make an appropriate response to capitulum explants and no regeneration was observed in this condition. The medium containing 4 mg/l BA and 0.2 mg/l IAA indicated the highest percentage of regeneration in all genotypes.
The highest regeneration was observed in Sunway genotype with an average of 21.96%. On the other hand no regeneration was observed in Eagle genotype. In terms of the number of regenerated plantlet, the highest number (61.2) was attributed to the Sunway genotype while no plantlet was recorded for Eagle genotype. No significant differences were also observed between Pink Snow and Dune genotypes.
For the proliferation stage, only Sunway genotype was utilized due to its vigorous growth in comparison to other genotypes. In this stage, the highest (6 regenerated plantlets) and the lowest (1 regenerated plantlet) regeneration rate were observed in MS medium containing 2 mg/l BA and hormone-free medium, respectively. Hormone-free ½ MS medium and ½ MS medium containing 1 mg/l IAA or IBA, indicated the highest rooting rate (100% rooting) while medium containing 1 mg/l NAA showed 55% rooting rate. It seems that the application of NAA in the medium composition had the lowestimpact on the rooting of regenerated plantlets. At the end of the experiment, the highest (90.42%) and the lowest (47.5%) acclimation rate was obtained in peat moss + cocopeat + fungicide medium and perlite medium, respectively.
Conclusions: Generally, for shoot induction of gerbera through capitulum culture, application of MS medium containing 4 mg/l BA and 0.2 mg/l IAA is recommended. It is also concluded that for proliferation stage, the MS medium containing 2 mg/l BA showed the highest rate of regeneration. Using of Hormone-free ½ MS medium is economically affordable. Finally for acclimation of the plantlets, application of peat moss + cocopeat + fungicide medium is recommended.
Shadi Mohamadi-Nejad; M. Gholami; Mahmood Esna-Ashari
Abstract
This research was conducted to study the factors affecting establishment, growth and shoot proliferation of Persian walnut, genotype Z60. Explant establishment was studied through a factorial experiment based on a completely randomized design with two factors including culture media (DKW and WPM) and ...
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This research was conducted to study the factors affecting establishment, growth and shoot proliferation of Persian walnut, genotype Z60. Explant establishment was studied through a factorial experiment based on a completely randomized design with two factors including culture media (DKW and WPM) and BA concentration (0 (control), 0.5 and 1.0 µM). Single-node explants were prepared from the young branches of Z60 trees in the middle of May. Although the effect of two culture media on the growth characteristics had no significant difference, but mean comparison of the data with this regard showed that DKW medium performed better than WPM. No significant difference was observed between the two BA concentrations, but significant difference was between two concentrations (0.5 and 1.0 µM) with 0 (control). In shoot proliferation experiment, two cytokine hormones (BA and Kinetin) in three concentrations (4.4, 6.6 and 8.8 µM) were studied in DKW medium. The data obtained from this part of experiments were analyzed through unbalanced completely randomized design. The effect of different hormonal treatments and their concentrations on Z60 genotype growth characteristics showed that 8.8 µM BA was more effective in compared to the other two treatments. However, no significant difference was observed between the three concentrations with this respect.
Seyyedeh Mahdiyeh Kharrazi; Seyyed Hossein Nemati; Ali Tehranifar; Abdolreza Bagheri; Ahmad Sharifi
Abstract
Carnation is considered as the world's third most important cut flower. Tissue culture techniques offer suitable method for micropropagation of this ornamental plant. However, one of the problems during in vitro culture of carnation is vitrification. Ratio of ammonium to nitrate and agar concentrations ...
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Carnation is considered as the world's third most important cut flower. Tissue culture techniques offer suitable method for micropropagation of this ornamental plant. However, one of the problems during in vitro culture of carnation is vitrification. Ratio of ammonium to nitrate and agar concentrations in the medium affect this phenomenon. Therefore, in this study the effect of these factors on the rate of proliferation and the vitrification of carnation (Dianthus caryophyllus L.) cultivar Innove Orange Bogr, was evaluated. In this investigation lateral buds were cultured on MS medium containing 1 mg/l BA, 0.1 mg/l NAA and with different concentrations of agar and different ratio of ammonium to nitrate. The results showed that increasing in the agar concentration to 12 g/l lead to decreasing the rate of vitrification but regeneration also declined. Increase of agar concentration cause limitation in nutrient absorption by plants. Also, decrease in the ratio of ammonium to nitrate in the medium reduces the amount of vitrification, but did not result in adverse effects on plant regeneration rates. Multiple regressions showed that the effect of ammonium to nitrate ratio on vitrification was higher than agar concentration. So by considering the amount of shoot regeneration and vitrification, to obtain the most normal shoots, the concentration of 10 g/l agar with ammonium to nitrate ratio 1:6, is recommended.
