Breeding and Biotechnology of Plant and Flower
Ahmad Sharifi; Maryam Moradiyan; Nasim Safari; Azadeh Khadem; Seyyedeh Mahdiyeh Kharrazi
Abstract
Introduction: Ornamental foliage plants are commonly used for beautifying indoor spaces. Consequently, determining the best method of mass propagation in a short time, is necessary for these plants. For this purpose, an experiment was designed and performed to micropropagate the Singonium ornamental ...
Read More
Introduction: Ornamental foliage plants are commonly used for beautifying indoor spaces. Consequently, determining the best method of mass propagation in a short time, is necessary for these plants. For this purpose, an experiment was designed and performed to micropropagate the Singonium ornamental plant.Materials and Methods: For the first stage, the effect of different plant growth plant growth regulators on the regeneration of nodule explants was evaluated. In this experiment, 1 cm nodal explants were placed in semi-solid MS culture medium containing different concentrations of BA and Kin (0, 1, 2, 3 and 4 mg/l) in combination with 0.2 mg/l IAA. This experiment was performed as a factorial based on a completely randomized design with four replications. The first factor included different types of cytokinin (BA and Kin) and the second factor included different concentrations (0, 1, 2, 3 and 4 mg/l). In the second stage, the effect of different types of culture medium and its different concentrations on plantlet proliferation was investigated. This study was performed as a factorial experiment based on a completely randomized design with five replications. The first factor included the type of culture medium (MS and B5) and the second factor was the different concentrations of culture medium (0.5 and 1). In the third stage of the experiment, the acclimation of in vitro plantlet was investigated. This experiment was performed as a completely randomized design with three replications. The experimental treatments included different culture media: vermiculite, peat moss, vermiculite + peat moss, perlite + peat moss, perlite, coco peat + vermiculite, coco peat + perlite, coco peat and rock wool.Results and Discussion: According to the results of the first experiment, it was found that the use of cytokinin in MS culture medium is effective on plant regeneration. The highest number of regenerated plantlet was observed in culture medium containing 4 mg/l BA with 0.2 mg/l IAA. It is noteworthy that with increasing BA concentration in the culture medium, the plant height decreased, but in contrast, the number of produced plantlets increased. Benzyl aminopurine (BAP) has been introduced as the most important and effective cytokinin in inducing and increasing branching in plants. Research has shown that the use of external benzyl adenine affects plant growth by affecting plant cells or by controlling the accumulation of a number of cytokinin compounds. As a result, the use of cytokinins in culture medium under in vitro culture conditions is necessary to induce and increase cell division. According to the second experimental results, produced plantlets in MS culture medium had higher height, number of roots and root length compared to B5 culture medium. Results also demonstrated that the use of ½ MS in the propagation stage of this plant is appropriate due to the improvement of growth traits such as plantlet height and root length. The use of optimal and suitable culture medium is very effective in the success of plant micropropagation. In the present study, the use of MS culture medium showed better performance compared to B5 culture medium. The appropriate amount of components, better ion strength and more minerals in this culture medium compared to B5 culture medium are probably the factors influencing its superiority in in vitro culture. In the acclimation stage, the use of vermiculite + peat moss culture medium led to 100% adaptation of plants and improvement of growth traits in the plant.Conclusion: The results showed that the type and concentration of cytokinin had a significant effect on the most of the evaluated parameters. With increasing the concentration of cytokinin in the culture medium, the number of regenerated plantlet was increased, but on the other hand, the height of regenerated plantlet also decreased. The use of culture medium containing BA compared to KIN had a more pronounced effect on increasing the number of regenerated plantlets. Application of MS medium compared to B5 medium was more effective in increasing plantlet height, root length, number of roots and number of produced plantlets. Also, half-strength MS medium, increased plantlet height and root length. Therefore, at this stage of propagation, the application of ½ MS culture medium is recommended. In the acclimation stage, it can be stated that the use of vermiculite substrate in combination with peat moss is a suitable option considering 100% compatibility of syngonium plantlets and improvement of growth traits in comparison with other substrates.
Seyyedeh Mahdiyeh Kharrazi; Ahmad Sharifi; Saba Nejatizadeh; Azadeh Khadem; Maryam Moradian
Abstract
Introduction: Considering the occurrence of successive droughts in our country and the necessity of optimal water consumption, the use of modern technologies such as closed systems to increase the efficiency of fertilizer and water use will have an effective role in reducing production costs and increasing ...
Read More
Introduction: Considering the occurrence of successive droughts in our country and the necessity of optimal water consumption, the use of modern technologies such as closed systems to increase the efficiency of fertilizer and water use will have an effective role in reducing production costs and increasing yield. The Nutrient Film Technique (NFT) system is one of the hydroponic culture systems in which the nutrient solution is circulated continuously. In this system, a thin layer of nutrient solution will be available to the plant roots, which has a significant effect on reducing fertilizer and water consumption.
Materials and Methods: The present study was conducted to select an optimal system for cultivation of Gerbera plantlets. Plantlets were cultivated in different systems after the acclimation stage: Integrated bedding system as a closed system containing different culture media (Perlite, vermiculite, vermiculite: perlite, cocopeat: perlite and rock wool) and NFT hydroponic system as a closed system. For fertilization, the following fertilizer combination (mM) was used: K2SO4 (0.22), KNO3 (3.62), KH2PO4 (0.71), NH4H2PO4 (0.35), NH4NO3 (0.53), Ca (NO3)2,4H2O (1.48), MgSO4, 7H2O (0.4), MnCl2, 4H2O (0.0049), H3BO3 (0.020), ZnSO4 (0.0061), CuSO4, 5H2O (0.00048), NaMoO4, 2H2O (0.00058), FeSO4, 7H2O (0.0348), Na2EDTA (0.0384). The experiment was conducted in a completely randomized design with six treatments in six replicates. During six months, the growth parameters of the plants including number of leaves, petiole length, fresh and dry shoot weight, leaf chlorosis percentage, leaf necrosis percentage, flower number, flower diameter, flowering stem height, number of days to flowering, end diameter of the stalk and the middle diameter of the stalk were evaluated. Data preparation was done in Excel and data analysis was performed using the Jump 8 software. Mean comparison between treatments was performed with LSD test at 5% probability level and charts were drawn using the Excel program.
Results and Discussion: The results showed that there was a significant difference between treatments for the number of leaves (p <0.01). Seedlings cultivated in the vermiculite culture medium produced the highest number of leaves; however, there was no significant difference between seedlings cultured in vermiculite and vermiculite: perlite media. The lowest number of produced leaves was observed in plantlets grown in the NFT system. Also, the seedlings grown in the rock wool medium had no significant difference with the NFT system. In this regard, the drought stress on plants and the consequent poor growth of plantlets reduced the number of produced leaves. The percentage of necrotic leaves in the NFT system was more than twice the vermiculite culture medium. There was no significant difference between cocopeat: perlite, perlite, rock wool, and NFT systems. Also, the lowest amount of necrotic leaves was found in the vermiculite culture medium, which did not have a significant difference with vermiculite: perlite culture medium. Low levels of leaf necrosis in these treatments indicate the optimal absorption of nutrients and the proper growth of plantlets in these culture media. The results showed that plantlets cultivated in the vermiculite and vermiculite: perlite flowered more quickly than other culture media and also produced more flowers. Plantlets grown in the rock wool medium did not show the desirable performance, which is due to drought stress. Besides, the use of cocopeat in the culture medium did not have a beneficial effect on plants. Measuring the initial electrical conductivity in the cocopeat culture medium also indicates a high EC concentration in this culture medium, which could affect the growth parameters of the plant and lead to poor vegetative growth of plantlets. Since Gerbera plant has bulky roots, the roots of this plant cannot be developed well in the NFT system, so the use of the NFT system is not suitable for Gerbera cultivation. The best performance of plant samples was obtained from vermiculite culture media, but since there were no significant differences between vermiculite and vermiculite: perlite, so to reduce production costs, the use of vermiculite: perlite culture medium in the closed system is recommended for the cultivation of Gerbera plant.
Conclusion: Since Gerbera plant has bulky roots, the roots of this plant cannot be developed well in the NFT system, so the use of the NFT system is not suitable for Gerbera cultivation. The best performance of plant samples was obtained from vermiculite culture media, but since there were no significant differences between vermiculite and vermiculite: perlite, so to reduce production costs, the use of vermiculite: perlite culture medium in the closed system is recommended for the cultivation of Gerbera plant.
Ahmad Sharif; Seyyedeh Mahdiyeh Kharrazi; Saba Nejatizadeh; Azadeh Khadem; Maryam Moradian
Abstract
Introduction: In traditional agriculture, a high concentration of nutrients is generally available to the plant, and a large amount of it will be leached out and is not available to the plant. But, if properly managed, the nutritional needs of the plant can be identified; it can increase the efficiency ...
Read More
Introduction: In traditional agriculture, a high concentration of nutrients is generally available to the plant, and a large amount of it will be leached out and is not available to the plant. But, if properly managed, the nutritional needs of the plant can be identified; it can increase the efficiency of fertilizer use and also prevent the environmental pollution caused by excessive use of chemical fertilizers in the country. Therefore, the aim of this study was to increase the fertilizer utilization efficiency by choosing optimal fertilizer treatment and its optimum level for acclimation and optimum growth of gerbera tissue culture plantlets.
Material and methods: In the first experiment, different fertilizer treatments with different proportions of NPK were evaluated in a completely randomized design with 10 replications. In the second experiment, the different concentrations of the secondary group treatment (0.5x, 1x and 1.5x) were evaluated to determine the optimum level of fertilizer treatment. This experiment also was conducted in a completely randomized design with 15 replications. At the end of each experiment different parameters such as leaf number, petiole length, shoot dry and fresh weight, main root number, root length, secondary root number, root volume, root dry and fresh weight, chlorophyll a, b and total content were measured. Data preparation was done in Excel and data analysis was performed using the Jump 8 software. Mean comparison between treatments was performed with LSD test at 5% probability level and charts were drawn using Excel program.
Results and discussion: The results showed that the maximum root length, root volume, root dry and fresh weight and secondary root number was obtained from plantlets that was treated by the fertilizer treatment of the second group: K2SO4 (0.22 mM), KNO3 (3.62 mM), KH2PO4 (0.71 mM), NH4H2PO4 (0.35 mM), NH4NO3 (0.53 mM), Ca(NO3)2,4H2O (1.48 mM), MgSO4, 7H2O (0.4 mM), MnCl2, 4H2O (0.0049 mM), H3BO3 (0.020 mM), ZnSO4 (0.0061 mM), CuSO4, 5H2O (0.00048 mM), NaMoO4, 2H2O (0.00058 mM), FeSO4, 7H2O (0.0348 mM), Na2EDTA (0.0384 mM). So among the different fertilizer treatment, application of the fertilizer treatment of the second group was recommended. Calculation of nitrate and ammonium content used in six fertilizer treatments showed that the amount of ammonium used in fertilizer had a significant effect on root number and root dry weight. The maximum root number and root dry weight were observed in the second fertilizer group and then in the first fertilizer group. Urea was not used as a source of nitrogen in the fertilizer formula of these two treatments, while in other fertilizer treatments; urea fertilizer was used in addition to other sources of nitrogen supply. Since urea is converted into ammonium before its absorption by the plant, its application in the fertilizer formula has an effect on the amount of ammonium used in the fertilizer composition. It increases the ratio of ammonium to nitrate in fertilizer composition, which in turn influences root function. The ratio of potassium to phosphorus in the research of Khalaj et al. (4.40) is approximately as the same as the ratio of potassium to phosphorus used in the second group fertilizer treatment (4.50). The results of this ratio were also corresponded to Zheng et al. (4.6), Paradikovic et al (4.4), Hahn et al (4), Savvas and Gizas (4.8).The results of second experiment showed that plantlets grown under 1.5x concentration of second group fertilizer had better growth indices than two other treatments and had higher means in terms of root and shoot dry weight and petiole length. After counting the number of produced leaves at the end of the experiment, signs of leaf necrosis was observed under some treatments. Plantlets treated with 1 and 0.5 x concentrations of the second group treatment showed the highest incidence of leaf necrosis. Application of 1.5 x concentration of the second group treatment resulted in a 40% decrease in leaf necrosis symptoms compared to the other treatments. Also, the highest percentage of healthy leaves was obtained from 1.5 x concentration of the second group treatment, which showed a significant difference with the other treatments.
Conclusion: Generally, for the purpose of acclimation and optimal growth of gerbera tissue culture plantlets, fertilizer treatment of the second group {15(N), 10(P2O5), 30(K2O), 11.10(CaO), 2.10(MgO)} at a concentration of 1.5x is recommended.
Ahmad Sharifi; Azadeh Khadem; Maryam Moradian; Seyyedeh Mahdiyeh Kharrazi
Abstract
Introduction: 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 ...
Read More
Introduction: 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.
Materials and 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.
Results and Discussion: 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.
Conclusion: 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.
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 ...
Read More
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.
