Effects of zinc and nitrogen application on agronomic traits and qualitative characteristic of sunflower in saline condition
This present study was performed at the Department of Soil Science of Karaj Branch, during the two seasons of 2008 to 2009 and 2009 to 2010. The experimental design aimed to study the response of sunflower to different nitrogen and zinc fertilizer levels under two doses of salinity stress. The obtained results from the two years showed that nitrogen increased seed yield while there was no significant differences between the two nitrogen levels; also, results showed that zinc application had not significant effect on seed yield. Conversely, salinity decreased seed yield and yield components dramatically. Based on mean comparison, plant height increased on account of nitrogen and zinc application. Nitrogen fertilizer application improved seed number per silique and 1000-seed weight over two years. Among yield components only number of seed per silique was affected by zinc and increased in the first year. Oil percentage decreased due to nitrogen, zinc and salinity in the first year but zinc had no significant effect on oil in the second year. Salinity stress increased glucosinolate and protein content. Other treatments had no significant effect on these traits. Salt stress induction decreased N, P, K, Ca and Mg content while increased Na, Cl and Na/K ratio.
Keywords: Sunflower, nitrogen, salinity, yield and yield components, zinc