The experiment was aimed to study the effect of colchicine concentrations (0.025, 0.05, 0.1 and 0.2%) and treatment times (8, 24 and 48 h) on polyploidy induction and morphological characteristics in Petroselinum crispum. Polyploidy induction was carried out in two independent experiments; seed treatment under in vivo, and node treatment under in vitro condition. Polyploids were confirmed by chromosome counts, density and size of stomata and other morphological characters. The survival rate for nodes and seeds decreased significantly with increasing concentration of colchicine and its treatment duration. Moreover, the induction of polyploidy was better in the node explants compared with the seeds. The maximum amount of tetraploidization of plants from the seeds was achieved at 0.05% colchicine after 24 and 48 h incubation. The most induction of the tetraploid plants was observed 24 h after treatment with 0.05% and 0.1% colchicine under in vivo and in vitro conditions, respectively. Furthermore, morphological measurements revealed that the size of the stomata and leaves in tetraploid plants was larger than those in diploid plants. However, the density of stomata was decreased in tetraploid plants as compared to the diploids.

No abstract

In this study, the effect of methyl jasmonate (MJ) and ultrasound (US), individually and in combination with L-tyrosine, on the stimulation of thebaine production in Papaver bracteatum cell suspension cultures was studied. The addition of L-tyrosine did not significantly affect the cell biomass, but significantly increased the thebaine yield of cells compared with the control. The synergistic effects of MJ and L-tyrosine in the combined treatment of 100 μM MJ and 2 mM L-tyrosine increased the thebaine yield of cells up to 84.62 mg L(- 1) at 6 days after treatment. Sonication of the cells for 20 s caused a significant decrease in cell growth and biomass, whereas the thebaine yield increased up to 39.60 mg L(- 1) at 6 days after treatment. The combination of US (10 s) and L-tyrosine feeding (2 mM) significantly increased the production of thebaine in comparison to individual utilisation of 2 mM L-tyrosine and US (10 s).

SummaryIn this study the effect of different colchicine concentrations (0.025, 0.05, 0.1 and 0.2%) and treatment time (8, 24 and 48 h) on in vitro polyploidy induction from shoot tips was investigated as a factorial experiment based on completely randomized design with three replications. Polyploidy induction was confirmed by chromosome counts, size and number of stomata and other morphological characters. By assessment of different media, it was revealed that the suitable medium for regeneration of shoot tips is MS medium supplemented with 0.1 mg L 1 IBA (indole-3-butyric acid) and 1 or 2 mg L 1 BAP (6-benzylaminopurine) or 2 mg L 1 TDZ (thidiazuron). In addition, MS medium supplemented with 1 mg L 1 NAA (1-naphthaleneacetic acid) and 0.5 or 1 mg L 1 IBA led to the maximum rooting of plantlets. With increasing colchicine concentration and its treatment duration, explants survival and their rooting considerably decreased. The results revealed that 0.1% concentration of colchicine with 48 h of treatment established the maximum amount of the in vitro induced tetraploid plantlets. The derived tetraploid plantlets had bigger stomata with lower density. Chlorophyll content in tetraploid plantlets was significantly higher than diploids, and they also showed an elevated level of antioxidant enzymes, protein and soluble carbohydrate contents as compared with diploids.

The seeds were surface-sterilized with 70% (v/v) ethanol for 45 s and 2.5% (w/v) sodium hypochlorite solution for 12 min, and then rinsed 3 times in sterile distilled water. The seeds were then germinated on MS medium (Murashige and Skoog, 1962) solidified with 8 g/L plant agar, and maintained in a growth chamber at 25 ± 2 °C with a 16-h photoperiod of cool white fluorescent light (400-500 lx).

An efficient regeneration system is a pre-requisite for the application of genetic transformation and functional

In the present study, the effects of ultrasound and plant growth regulators on in vitro callogenesis and secondary metabolites production in saffron calli were investigated. Accordingly, the saffron corms surface sterilized, sonicated and cultured on different concentrations of plant growth regulators (0.5, 1, 2 and 4 mg L-1 2,4-D or NAA in combination with 0.5 and 1 mg L-1 Kin or BAP). The percentage of callus induction, callus yield (fresh weight) and embryogenic callus formation were recorded and secondary metabolites of calli were measured by UV/VIS spectrophotometer three months after culture. The results indicated that sonication of the saffron corm explants significantly increased the in vitro callus induction and growth. So, the highest callus induction (100%) and yield (4.68 g) was achieved with sonicated explants cultured on MS medium supplemented with 2 mg L-1 1-naphthaleneacetic acid (NAA) and 0.5 mg L-1 kinetin (Kin). Somatic embryogenesis was significantly influenced by plant growth regulator regimes and the MS medium supplemented with 0.5 mg L-1 2,4-dichlorophenoxyacetic acid (2,4-D) plus 0.5 mg L-1 6-benzylaminopurine (BAP) and 0.5 mg L-1 NAA plus 0.5 mg L-1 Kin exhibited the highest percentage (75 and 72, respectively) of somatic embryogenesis. Secondary metabolite content of the callus cells was significantly different among the plant growth regulator regimes and the highest production of picrocrocin and safranal were occurred on the medium containing 0.5 mg L-1 2,4-D plus 0.5 mg L-1 BAP and 1 mg L-1 NAA plus 1 mg L-1 BAP.

For overcoming interspecific incompatibility, protoplast combination method is a proper procedure for making a new plant with desired traits. For this purpose, protoplast preparation is a first and important step. Hence, experiments were conducted to evaluate various combinations of cellulose, pectinase and their treatment times on protoplast production and protoplast viability in Lilium ledebeourii Bioss. The results of experiment revealed that the protoplast yield was significantly affected by different treatment levels. Cellulase at 4% gave the highest numbers of protoplasts at 3.71×10 5 protoplast/g FW. Pectinase at 1% gave the highest numbers of protoplast. For treatment times, the highest yield of protoplast was with leaf explants treated for 24 h. Analysis of variance indicated that concentration, time and three-way interaction of cellulase, pectinase and time were significant at p<0.01. Cellulase at 4% and pectinase at 0.2% for 24 h gave the highest viability. Interactions of cellulase × pectinase, cellulase × time, pectinase × time and cellulase × pectinase × treatment time were significant at P≤0.05 for protoplast number. The highest and lowest protoplast numbers were produced in media containing 4% cellulase and 1% pectinase for 24 h (6.65×10 5 protoplast/g FW) and 1% cellulase and 0.2% pectinase for 12 h, respectively. It's concluded that, the best treatment for isolation of Lilium protoplast was 4% cellulase and 1% pectinase for 24 h.