The effects of root application of silicon on growth and photosynthetic pigments of wheat under lead stress

In this research, the effect of silicon application (as potassium silicate; 0, 100 and 200 mM) was studied on Thriticum aestivum cv. Chamran and cv. Shiroudi under lead stress (as lead acetate; 0 and 0.126 g/ Kg). For this aim the experiment was conducted as a completely randomized design in a pot method. Results showed that the lead stress decreased the fresh and dry weights of shoot in cv. Chamran. Moreover, lead stress significantly decreased the photosynthetic pigments (chlorophyll a and b, total chlorophyll and carotenoids) contents of cv. Chamran. The induced decreases by lead in photosynthetic pigments content of cv. Shiroudi were not significant. Silicon application at concentration of 100 mM in lead stressed plants significantly increased the relative water content of cv. Chamran and at concentration of 200 mM significantly increased the length and dry and fresh weights of shoot in cv. Shiroudi. Furthermore, silicon application in cv. Shiroudi significantly increased the chlorophyll a content at both concentration and total chlorophyll at concentration of 100 mM. Even though the effect of silicon application on photosynthetic pigments content of lead stressed plants in cv. Chamran was not significant. The results of this study showed that cv. Shiroudi is relatively resistant to lead stress compared to cv. Chamran and silicon application could improve the growth parameters by protection the photosynthetic pigments in this cultivar.

کلیدواژه ها:

Lead ، Photosynthetic Pigments ، Silicon ، Wheat