Mohammad Bahmani, Sonia Yousefi, Davoud Kartolinezhad,
Volume 3, Issue 1 ((Spring and Summer) 2016)
Abstract
In this study, the effect of different doses of gamma radiation was investigated on seed germination factors of Caper species. Gamma irradiation was performed using a cobalt-60 radiation with the radiation speed of 0.018 Gray/second and five doses of gamma radiation (0, 20, 40, 60 and 100 Gray) in a completely randomized design with 4 replication. The results showed that gamma radiation significantly affects some of the seed germination factors. So that the 100 Gray treatment increased the germination percentage up to 43.2% as compared with other treatments. The average time of germination in seeds treated with gamma decreased 0.91 days rather than control. Length of the stem let in gamma treatments increased 62.3% rather than control; so that the fresh and dry weight of stem let at 100 Gray were respectively increased 171.4 and 27.3% in comparison with the control. The fresh and dry weight of rootlets were respectively increased 417.9% and 668% rather than the control one. Seed vigor at 100 Gray was 32.3% higher than the control. From among the different studied doses, 100 Gray showed the highest influence on the seed germination and physiology although the induced changes were in low amounts. This study revealed that gamma irradiation has not major influences on improving seed germination characteristics of Caper shrubs.
Seyedeh Tina Mousavi Kani, Davoud Kartoolinejad, Zohreh Bahrami, Ali Asghar Zolfaghari, Elahe Nikouee,
Volume 9, Issue 1 ((Spring and Summer) 2022)
Abstract
Extended Abstract
Introduction: Nowadays, due to land use change and destruction of natural resources induced by human activities, attention to desertification has immensely become widespread. One of the most important species for biological rehabilitation of desert areas on a large scale is the hawthorn plant. Hawthorn is a plant belonging to the family Amaranthaceae, the two species of which are called white saxaul (Haloxylon persicum Bunge ex Boissier & Buhse) and black saxaul (Haloxylon aphyllum (Minkw.) Iljin) are more notorious and widespread in Iran. These plants own extensive root systems and stabilize running sands. The aim of this study was to investigate the effect of mesoporous titanium dioxide nanoparticles on germination traits of black saxaul seeds under drought stress, as an important species in desert areas.
Materials and Methods: The experiment was performed as a factorial experiment in a completely randomized design with 3 replications. Experimental treatments included five titanium nano dioxides with concentrations of 0, 25, 50, 100 and 200 mg / l and six drought stress levels including 0, -4, -8, -12, -16 and -20 bar. After nanopriming, black saxaul seeds were subjected to drought stress for 15 days in a germinator at a temperature of 20 °C with four replications. After germination, in each of the treatments, germination percentage (GP), germination rate (GS), mean germination time (MGT) and seed vigor index (VI) were calculated.
Results: The results of two-way ANOVA and mean comparison of germination indices showed that the highest germination percentage (74%) belonged to the zero level of stress treatment with a concentration of 200 mg/l and the lowest one (3%) belonged to -20 bar treatment with 25 and 200 mg/l nano-titanium dioxide. With increasing drought stress intensity from zero to -20 bar level, germination rate decreased from 7.01 to 0.43 seeds per day. The highest amount of seed vigor index at zero drought level belonged to the treatment of 200 mg/l concentration of nano-titanium, with a rate of 325.77.
Conclusion: The results showed that germination indices and initial growth of black saxaul seeds decreased in all primed and unprimed treatments with increasing drought stress, and nanopriming with titanium dioxide had a positive effect on seed germination traits.
Highlights:
1- Seed priming using mesoporous nano-titanium dioxide improved the germination percentage of black saxaul seeds under drought stress.
2- The concentration of 200 mg/l of mesoporous nano titanium dioxide revealed a better effect on seed germination index, mean germination time, germination rate and percentage
3- Seed nano priming using titanium dioxide did not have much effect on the growth characteristics of black saxaul seedlings at higher levels of drought stress.
