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Introduction Genetic diversity is one of the major goals of plant breeding. Mutation induction is a method to increase genetic variety that is used in plant breeding along with selection, recombination or a combination of the both. Rosa persica Michx can serve as a valuable genetic resource for breeding programs, especially due to the market demand for variety in rose cultivars as well as its drought resistance. In two independent experiments, this study examined the effect of ethyl methane sulfonate (EMS) as a chemical mutagen on seed germination and seedling characteristics of Rosa persica. Materials and Methods The seeds of Rosa persica Mich.seeds were collected from an adult shrub on the Arak University campus, Karbala St., Sardasht (34° N, 49.6° E) and an altitude of 1872 m above sea level during mid-summer. The seeds were separated from the hips by a sharp scalpel and the damaged and abnormal seeds were removed. Before applying the cold stratification, the seeds were washed for several hours and then placed in layers of wet sand at 4 ° C for 60 days. First, the effects of 0, 0.2, and 0.3% EMS at 4, 8 and 12 hours on seed germination characteristics were examined. Second, 0, 0.2, and 0.3 concentrations of EMS at 4 and 8 hours were studied on reproductive buds. Seed germination characteristics such as final germination percentage, germination rate index, coefficient velocity germination, germination rate, mean daily germination, daily germination speed, mean germination rate, germination index, seed vigor, seed dormancy and seedling vegetative traits such as stem lengths, root lengths, and leaf number are evaluated at first experiment. In second experiment, flower diameter, flower opening rate, number of necrotic buds and the number of seeds in each hip were measured. Results and Discussion The results showed that increasing the concentration of EMS and the time of seed treatment caused a further decrease in germination indices. In 0.3% EMS treatment for 8 hours on seeds, traits such as germination percentage, germination rate index and daily germination were reduced to zero. According to the results of the second experiment, leaf and seedling lengths were longer at 0.2 and 0.3% EMS concentrations and at 4 h incubation. There was a decline in the number of seeds per hip and an increase in necrotic buds with increasing concentration and time of EMS application. In order to succeed in a breeding program using mutagenic methods, the appropriate concentration and time must first be optimized. To determine the best concentration of mutagens, there are two important factors to consider: first, that the concentration should not be so high as to destroy plants, and second, that the applied concentration should be selected moderately. Although, that the frequency of mutations occurs sufficiently. Conclusion In order to induce a positive mutation and diversity in Iranian roses for the purpose of introducing a new cultivar, seed treatment with a concentration of 0.3% EMS and an incubation time of 4 h is recommended. It is also recommended to apply a concentration of 0.2% EMS on the reproductive buds for 4 h to induce mutations. [ABSTRACT FROM AUTHOR]

Aim: Nowadays, in the industrial areas, there is a problem of simultaneous contamination of soil with heavy metals and lack of organic matter that can impede the growth of plants. Thus, this study was done to investigate the effect of organic amendments on decreases plant abiotic stress in a soil cocontaminated with lead (Pb) and cadmium (Cd) under ornamental sunflower cultivation. Materials and Methods: Treatments consisted of applying vermicompost (0, 15, and 30 t/ha) and soil polluted with Cd (0, 5, 10, and 15 mg/kg soil) and Pb (0, 400, and 600 mg/kg soil), and the plant used in this experiment was ornamental sunflower. After 8 weeks of the experiment, plants were harvested, and soil and plant Zn and Fe were measured using the atomic absorption spectroscopy. In addition, the ascorbate peroxidase (APX) and peroxidase (POX) of the plant were measured. Results: The application of 15 and 30 t/ha vermicompost significantly depressed the APX and POX activity by 12.1% and 14.6%, respectively. While the plant Fe and Zn concentration was significantly increased by 11.1% and 13.6%, respectively. Increasing soil pollution to Cd to 15 mg/kg soil significantly increased the APX and POX enzyme activities of the sunflower by 14.6% and 13.3%, respectively. Conclusion: It can be concluded that the interaction effect of Fe and Zn with heavy metal can help to decrease the plant abiotic stress that is a positive point in the environmental research. However, the role of organic amendments in decreasing heavy metals availability cannot be ignored. [ABSTRACT FROM AUTHOR]

Prunus scoparia is a wild deciduous shrub, usually living on dry calcareous soils of the rocky mountains and has been used as a grafting rootstock for domesticated almonds to provide drought resistance. In the current study, micropropagation ability of P. scoparia was investigated using cytokinin and auxin. Uniform nodal shoot pieces (3–5 cm in length) of seedlings were used as explants. The explants were disinfected with 10% sodium hypochlorite solution. For adventitious shoot induction and proliferation, Murashige and Skoog (MS) media containing 7.00 g/l agar and 30.00 g/l sucrose containing five concentrations of benzyl adenine (BA) (0.00, 0.50, 1.00, 2.00, and 4.00 mg/1) and also containing six concentrations of Thidiazuron (TDZ) (0.00, 0.50, 1.00, 2.00, 5.00, and 7.00 mg/1) were compared. For rooting, in vitro shoots (2–3 cm) were transferred into ½ MS medium supplemented with 30 g/l sucrose, 7.50 g/l agar, and different concentrations of IBA (0.00, 0.25, 0.50, and 1.00 mg/l) and NAA (0.00, 0.25, 0.50, and 1.00 mg/l). Based on the results obtained for shoot proliferation, only 2.00 and 4.00 mg/l BA and 2.00 mg/l TDZ concentrations generated shoots, while other treatments did not show shoot proliferation. Among the three treatments that generated shoots, the best results for shoot number, leaf number, and leaf color quality were observed in media containing 2.00 mg/l TDZ. Based on the results obtained for rooting, the effect of IBA concentrations on the rooting percentage, root number, and root length was significant. Among IBA concentrations, only 0.50 mg/l IBA induced rooting, while there was no rooting in the media containing other IBA concentrations. None of the NAA concentrations showed rooting. In conclusion, MS culture medium supplemented with 2.00 mg/l TDZ and ½ MS culture medium supplemented with 0.50 mg/l IBA are suggested for in vitro shoot proliferation and rooting of P. scoparia, respectively. The results presented herein could be used for in vitro selection and micropropagation of P. scoparia. [ABSTRACT FROM AUTHOR]