Yazar "Pazuki, Arman" seçeneğine göre listele
Listeleniyor 1 - 11 / 11
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Doubled haploid sugar beet: an integrated view of factors influencing the processes of gynogenesis and chromosome doubling(Int Sugar Journal Ltd, 2017) Aflaki, Fatemeh; Pazuki, Arman; Gürel, Songül; Stevanato, Piergiorgio; Biancardi, Enrico; Gürel, EkremHaploid and doubled haploid plant production through unpollinated ovule culture, with diverse benefits and applications, is considered among the effective and advantageous breeding methods for sugar beet (Beta vulgaris L). Sugar beet is not responsive to androgenesis that is widely used for most plant species. It is a recalcitrant plant in vitro due to the very low spontaneous chromosome doubling and low gynogenesis rates. Thus, a steadily increasing gynogenesis efficiency has always been an important target. Given the lack of papers focusing on gynogenesis in sugar beet, this review covers haploid and doubled haploid production through ovule culture of unfertilized flowers as a practical method. Besides haploid and doubled haploid methods, factors affecting both gynogenesis and doubling rates are also reviewed. In addition, outlooks and possibilities for doubled haploid production are discussed, trying to capture the elusive concept of the factors applied and taking into account some of them, e.g. genotype, plant growth regulators, plant/explant physiology and growth condition, chemicals, in vitro and in vivo methods, and transgenic method. By providing enough information and new groundwork through novel and wide perspectives on factors affecting gynogenesis, it should be easier to collect knowledge useful for future research.Öğe Effects of cytokinins, gibberellic acid 3, and gibberellic acid 4/7 on in vitro growth, morphological traits, and content of steviol glycosides in Stevia rebaudiana(Elsevier France-Editions Scientifiques Medicales Elsevier, 2019) Pazuki, Arman; Aflaki, Fatemeh; Yücesan, Buhara; Gürel, SongülSteviol glycosides (SGs) and gibberellic acids share a part of their biosynthesis pathways. Despite the widespread studies on the effect of gibberellic acid 3 (GA(3)), the effect of gibberellic acid 4 and 7 (GA(4/7)) on Stevia rebaudiana has never been studied. This study aimed at a comparative evaluation of different hormone effects, i.e., 1 mg L(-1)GA(4/7), 1 mg L(-1)GA(3), or 0.5 mg L(-1)kinetin and 0.5 mg L-1 6-benzylaminopurine (BAP) (KB 0.5), on in vitro propagation, growth, morphological properties, and content of SGs in leaf samples of stevia. In comparison with the control group (hormone-free), the treatments of KB 0.5 or GA(3) produced the highest biomasses and largest leaf areas. The three hormonal treatments produced a similar number of leaves, the ratio of fresh to dry weight, and leaf length. GA(4/7) treated explants produced the highest ratio of leaf area to leaf length. The effect of Gk(4/7) on shoot elongation was greater than that of the control or even GA(3). While the effect of GA(3) on rebaudioside-A (Reb-A) production was similar to that of the control (16.2 and 18.04 mg g(-1), respectively), GA(4/7) resulted in a lower amount of it (13.31 mg g(-1)). Except for GA(4/7), which induced more stevioside accumulation, the treat.ments' effects were comparable to that of the control. The ratio of stevioside to Reb-A was the highest for GA(4/7) (2.62), followed by GA(3)(1.93), and then the two others. Sum of Reb-A and stevioside content was not changed by the use of any of the treatments.Öğe The effects of proline on in vitro proliferation and propagation of doubled haploid sugar beet (Beta Vulgaris)(2018) Pazuki, Arman; Aflaki, Fatemeh; Gürel, Songül; Ergül, Ali; Gürel, EkremDoubled haploid induction is one of the available methods normally used for sugar beet breeding. Gynogenic haploid explants of sugar beet induced with 1 or 2 mg L-1 6-benzylaminopurine were treated with 5 g L-1 colchicine, then subcultured on a solidified MS medium plus 0.2 mg L-1 kinetin. Colchicine doubled the chromosome number of 27.7% of the treated haploid explants. With the aim of increasing the number of doubled haploid explants, the effects of five levels of proline (0.0, 0.1, 0.2, 0.3, or 0.4 mM) on the explants’ proliferation, propagation, and shoot length were compared. With a large effect size (ES), proline at 0.3 mM induced the highest amount of proliferation, while proline-free medium resulted in the lowest amount of it. The highest propagation rates were observed for the explants treated on media with 0.2 and 0.3 mM proline (very large ES). Proline at 0.3 mM induced the shortest shoots (medium ES). A very strong positive correlation between proliferation and propagation, a moderate negative correlation between proliferation and length, and a strong negative correlation between propagation and length were observed. For the first time our results show beneficial effects of proline on in vitro proliferation and propagation of sugar beet.Öğe Gynogenesis induction in sugar beet (beta vulgaris) improved by 6-benzylaminopurine (BAP) and synergized with cold pretreatment(Springer India, 2018) Pazuki, Arman; Aflaki, Fatemeh; Gürel, Ekrem; Ergül, Ali; Gürel, SongülFor sugar beet (Beta vulgaris) breeding, producing homozygous lines through haploid and doubled haploid techniques are preferred over conventional and time-consuming methods. Doubled haploid sugar beet production necessitates inducing ovules to develop into haploid plants, referred to as gynogenesis. The protocol involves an interaction between cold pretreatment of six genotypes of sugar beet inflorescences at 4 degrees C for 1 week or more and 6-benzylaminopurine (BAP) concentrations (1 or 2 mg L-1) to increase the response rate of haploid embryo induction. Compared with freshly cultured ovules (6.49%), cold pretreatment for 1 week almost doubled the mean of haploid plantlet induction rate (11.3%), whereas pretreatment for more than 1 week was not as effective as the control. Addition of 2 mg L-1 BAP to the culture medium nearly doubled the induction rate of the cultured ovules (10.75%), followed by 1 mg L-1 BAP (7.78%) in comparison with hormone-free medium (5.69%). The highest gynogenesis rate (37.8%) was achieved when ovules were cultured on medium containing 2 mg L-1 BAP following 1-week cold pretreatment. This combination approximately tripled the mean total haploid embryo induction rate of all the genotypes to 16.3% in comparison with the control (5.74%). However, the addition of BAP resulted in vitrification proportionately. As a result, 2 mg L-1 BAP decreased the normal plantlet emergence (NPE) to one-third (7.59%) while 1 mg L-1 BAP had a moderate effect (NPE: 18.98%) in comparison with hormone-free treatment (NPE: 24.35%). The results indicate that the combination of cold pretreatment and BAP is very effective in inducing haploid plants from recalcitrant genotypes of sugar beet, but BAP can have both advantages and disadvantages.Öğe Identification and expressional profiling of putative MAX1 gene in sugar beet (Beta Vulgaris L.)(2020) Ünlü, Ercan Selçuk; Gürel, Songül; Aflaki, Fatemeh; Pazuki, Arman; Şahin, Günce; Gürel, EkremSugar beet is an industrial crop cultivated mostly for sucrose production. Today, modern hybridization applications have raised the sugar content to 20%. Considering the increased demand globally, it is required to develop new yield–increasing application strategies. This requires extensive knowledge of the genetic mechanisms to control plant growth and metabolism. Investigation of phytohormones is promising to increase our knowledge of plant growth and developmental processes. Strigolactones are recently introduced plant hormones. They are responsible for shoot and root architecture, and involved in development, communication, germination, and responses to stress. Four major proteins (AtD27, MAX1, MAX3, MAX4) are responsible for the strigolactone biosynthesis. MAX1 protein is essential for the distinct production of strigolactone molecules. The studies on strigolactones have been carried out mostly using Arabidopsis thaliana. There are only few studies on agriculturally important plants. No reports are available for the investigation of strigolactone biosynthesis in sugar beet (Beta vulgaris). In this manuscript, we profiled the expression of MAX1 gene in sugar beet treated with strigolactone hormones (rac-GR24, (±)-strigol and (±)-5-deoxystrigol) and a strigolactone biosynthesis inhibitor (TIS108). Our data suggest that MAX1 has a conserved biosynthetic and regulatory metabolism in sugar beet compared to previously investigated plant species.Öğe Investigation of seed germination indices for early selection of salinity tolerant genotypes: a case study in wheat(United Arab Emirates Univ, 2017) Aflaki, Fatemeh; Sedghi, Mohammad; Pazuki, Arman; Pessarakli, MohammadPlant establishment is highly correlated with successful germination and seedling growth, the most sensitive and critical stages. Abiotic stresses by their limiting and adverse effects on these stages finally result in poor yield. Therefore, investigating resistance to salinity among genotypes of a desired plant is highly recommended for anticipated drought seasons. To study the effects of salinity on seed germination and initial growth of seedlings, a factorial experiment was conducted based on a completely randomized design with four replicates using three wheat (Triticum aestivum) genotypes (Zagros, Gascogen and Kuhdasht). Salinity levels included 0 (control), 3.5, and 7 dS m(-1) (deci-Siemens per meter). The results indicated that salinity had a significant influence on different germination indices (P < 0.05). In all the genotypes, with an increase in salinity levels, indices including germination percentage, germination rate, seed vigor, coefficient of germination rate, coleoptile to plumule ratio, and daily germination mean decreased. Unlike the mentioned indices, the ratio of the radicle to plumule and the mean of germination time increased. Zagros genotype showed more tolerant than the other two. Based on these results, it seems that germination indices may be effectively used in selecting tolerant plants to salinity stress.Öğe Production of doubled haploid sugar beet (Beta vulgaris L.) plants through gynogenesis(Humana Press Inc, 2021) Gürel, Songül; Pazuki, Arman; Aflaki, Fatemeh; Gürel, Ekrem; Segui-Simarro, JMHaploid and doubled haploid plant production through unpollinated ovule culture, with diverse benefits and applications, is considered among the most effective and advantageous breeding method for sugar beet (Beta vulgaris L.). It is known that sugar beet is not responsive to androgenesis, which is widely used for most plant species. Sugar beet is a recalcitrant plant in vitro due to the very low spontaneous chromosome doubling and low gynogenesis rate. Thus, a steadily increasing gynogenesis efficiency has always been an important target for an efficient sugar beet breeding program. Given the scarcity of published papers focusing on gynogenesis in sugar beet, this chapter describes haploid and doubled haploid production through ovule culture of unfertilized flowers as a practical method.Öğe Production of doubled haploids in sugar beet (beta vulgaris): An efficient method by a multivariate experiment(Springer, 2018) Pazuki, Arman; Aflaki, Fatemeh; Gürel, Songül; Ergül, Ali; Gürel, EkremThe present paper describes a detailed study of a highly efficient protocol to multiply the number of haploids in sugar beet production and subsequent chromosome doubling. The protocol involves an experiment investigating factorial interactions between cold pretreatment, seven genotypes of sugar beet, and kinetin to improve haploid embryo induction. In addition, the effects of color of ovules and flower bud position on haploid embryo induction were investigated. After subjecting the data to analysis of variance or Student's t test (P < .05), the effect sizes of the independent variables were also estimated. Cold pretreatment was effective in stimulating the ovules. The haploid embryo induction rate for 1-week cold pretreated ovules (9.01%) was higher than that of freshly cultured ones (6.15%). In comparison with hormone-free medium (5.16%), the gynogenesis rate for the media supplemented with 0.05 or 0.5 mg L-l kinetin increased to 7.58 and 10.05%, respectively. The genotype responses were significantly different. Interactions of kinetin x cold pretreatment, genotype x hormonal treatment, genotype x cold pretreatment, and the three-way interaction were statistically significant. Moreover, the main effects of flower bud position, ovule color, and comma-form ovule on gynogenic response were significant. After investigating the effect of 5 g L-l colchicine for 3, 5, or 7 min on one genotype's (SG2) specimens, all the haploid plantlets from the other genotypes were treated for 5 min as the best treatment. The paper discusses interactions of the factors, which may be interesting for others aiming to breed doubled haploid sugar beet or possibly other related plant species.Öğe A robust method for haploid sugar beet in vitro proliferation and hyperhydricity reduction(Polish Soc Horticultural Sci, 2017) Pazuki, Arman; Aflaki, Fatemeh; Gürel, Ekrem; Ergül, Ali; Gürel, SongülSugar beet is recalcitrant to in vitro tissue culture. Usually, proliferation of in vitro cultured rosette explants is a prerequisite for micropropagation. Although hormonal treatments can induce proliferation in sugar beet rosette explants, they may also result in some side effects. In vitro culture of sugar beet explants and some hormonal treatments make them more prone to hyperhydricity. Effects of media with different concentrations of 6-benzylaminopurine (BAP) and kinetin (Kin) on the proliferation and hyperhydricity of haploid sugar beet explants were investigated. It was observed that 0.2 mg L-1 Kin, with a reasonable amount of proliferation and minimum rate of hyperhydricity, performed better than BAP in different concentrations and combinations. The effect sizes of the treatments on the dependent variables were large. The correlation between proliferation and hyperhydricity of the treated explants was statistically negative and the association was large. However, the hormonal treatments without BAP or with the lowest amount of it produced the highest proliferation rate with the least hyperhydricity. The coefficient of determination was R-2 quadratic = 0.885. The results suggest that, in comparison with BAP, Kin is a potent plant growth regulator for the proliferation of sugar beet haploid explants that causes the least hyperhydricity. Although explants proliferated better in the presence of 0.01 mg L-1 BAP in combination with Kin than under Kin alone, the hyperhydricity of the proliferated explants decreased their suitability for in vitro propagation.Öğe Strigolactone Plant Hormone's Role in Plant Stress Responses(Crc Press-Taylor & Francis Group, 2020) Aflaki, Fatemeh; Pazuki, Arman; Pessarakli, MohammadÖğe Ultraviolet Radiation Effects on Plants Harmful or Beneficial?(Crc Press-Taylor & Francis Group, 2020) Pazuki, Arman; Aflaki, Fatemeh; Pessarakli, Mohammad
