Effect of Foliar Application of Chemical Nano-Fertilizers on Physiological Traits of Saffron (.Crocus sativus L)

In order to investigate the effects of different types of nano-fertilizers on some of the physiological characteristics of saffron (i.e. antioxidant enzymes, reducing and non-reducing sugars, photosynthetic pigments, total phenol content and relative water content of leaf) the current experiment was conducted at Malayer University during 2014-2015 growing season. The study was performed based on randomized complete block design (RCBD) with six treatments and three replications. The experimental treatments were control and five different types of nano-fertilizers (iron: Fe, boron: B, manganese: Mn, potassium: K and zinc: Zn). The effects of experimental treatments on relative water content, protein and total phenol content, reducing and non-reducing sugars were significant but there was no significant effect on chlorophyll b, leaf carotenoids, Catalase and Proxidase activity. Although the difference between nano-fertilizers and control treatment for chlorophyll a and also total chlorophyll was not significant but the highest amount of chlorophyll a (1.53 mg.g-1 Fw) measured in Fe treatment and the lowest amount (0.93 mg.g-1 Fw) observed in Mn treatment. Based on results, all of the experimental treatment increased the relative water content of leaf comparing to control. The highest amount of total phenol content (0.27 mg.g-1 FW) with 10.5% increase compared to control observed in Mn treatment and just the difference of this treatment with control treatment was significant. By application of Zn, Mn, K and B nano-fertilizer leaf protein content comparing to control treatment significantly increased whereas the difference between Fe and control wasn’t significant. The highest concentration of leaf protein (1.56 mg.g-1 Fw) with 12% increase compared to control treatment observed in K and B treatments whereas the lowest concentration (1.36 mg.g-1 Fw) with 3% decrease compared to control was related to Fe treatment. The different response of studied characteristic to application of various nano-fertilizer showed that different physiological traits hadn’t the similar sensitivity to all of mineral nutrients therefore application of entire nano-fertilizers with the same concentration isn’t scientifically recommendable