Biotechnology and genetics
Ali Mohammad Mohit-Ardakani; Seyed Ebrahim Seifati; Ali Izanloo; Zahra Karimi-bekr
Abstract
In recent years, the use of saffron spice is increasing due to its medicinal properties and effective components. In addition to increasing crop production, increasing the quantity and quality of secondary metabolites is considered one of the most important objectives of plant breeding programs. On the ...
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In recent years, the use of saffron spice is increasing due to its medicinal properties and effective components. In addition to increasing crop production, increasing the quantity and quality of secondary metabolites is considered one of the most important objectives of plant breeding programs. On the other hand, the saffron plant has low genetic diversity due to the nature of vegetative propagation and induction of variation through mutagenesis is a suitable tool to achieve the desired diversity. Gamma radiation is one of the most widely used physical mutagens in plant breeding programs. In order to investigate the effect of gamma-ray on some growth and phytochemical indices of saffron plants, an experiment was conducted in an unbalanced complete randomized design with three treatments (Control, 15 and 18 Gy) at Yazd University. In this experiment, 15 and 18 Gy doses of gamma irradiation (Co60) were applied at Karaj Nuclear Agricultural Research Institute to induce mutations on collected saffron corms from Qaen, South Khorasan in August 2017. In this study, picrocrocin, safranal and crocin were measured in a 1% aqueous solution at 254, 330 and 440 nm wavelengths, respectively. Based on the results of this experiment, the effect of irradiation on picrocrocin and crocin was significant (P <0.001) and the observed amounts of these compounds (93.77 and 263.02) at the dose of 15 Gy were significantly higher than 18 Gy (92.34 and 262.73), while in terms of safranal content, the difference between radiation levels was not significant. Leaf area index and harvest index were also significant and showed the highest amount of these two indices at 15 Gy dose (3.06 and 0.14). In this study, although gamma radiation treatment could not significantly change the number of daughter corms between different levels of radiation and control, a significant reduction in relative chlorophyll content and an average weight of corms were observed compared to the control (without radiation). In general, the results of this study showed that in phytochemical traits as well as harvest index and leaf area, 15 Gy had a significant advantage over plants without radiation, but at higher levels of gamma radiation, probably due to degradation of genetic content and its effect on some biochemical parameters, 18 Gy plants failed to show acceptable results.
Agriculture
Seyyedeh Maliheh Mirhashemi; Mohammad Bannayan; Ahmad Nezami; Mahdi Nassiri Mahallati
Abstract
Leaf area index, light extinction coefficient and radiation use efficiency are important eco-physiological characteristics for realization of crops growth, development and radiation absorption. In order to determine the leaf area index (LAI), light extinction coefficient (K) and radiation use efficiency ...
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Leaf area index, light extinction coefficient and radiation use efficiency are important eco-physiological characteristics for realization of crops growth, development and radiation absorption. In order to determine the leaf area index (LAI), light extinction coefficient (K) and radiation use efficiency (RUE) of saffron during the first and second growing seasons, four experiments were started in 2011 and ended in 2014, at the Research Farm of the Agriculture Faculty, the Ferdowsi University of Mashhad, Iran. Saffron corms with weights between 13 to15 g and density of 50 plant.m2 were cultivated in 2011 and 2012. In all experimental years during the growing season, crop sampling was taken for required measurements including the leaf area index and shoot dry weight of saffron once every 14 days. The results showed that by increasing the age of saffron from 1 year to two years, the maximum LAI of saffron increased from 0.33 to 1.81, and light extinction coefficient decreased from 1.20 to 0.54. The increasing trend of LAI was coincident with fraction of absorbed radiation for all four years of the experiment. In the first and the second growing seasons, the amount of fraction of absorbed radiation gradually increased with increasing LAI and at 1083 and 1034 GDD reached its maximum value, respectively. In saffron farms when the plant was one year old and two years old, the mean value of RUE was 0.68 and 1.73 g.MJ-1 PAR, respectively. These results indicate that by increasing the saffron age and LAI, the value of K decreases and consequently radiation absorption and use efficiency will increase.
