INFLUENCE OF FILTER MUD CAKE FERTILIZATION UNDER LOW LEVELS OF NITROGEN ON YIELD AND ITS COMPONENTS FOR TWO SUNFLOWER CULTIVARS

Two field experiments were conducted at the Agricultural Exp. Farm of El-Azhar Univ. at Assiut, during 2008 and 2009 seasons to study the response of two cultivars of sunflower (Sakha-53 & Giza-102), to the application of different nitrogen rates (15, 30 and 45 kg /fed) and Filter Mud Cake (FMC) (0.0, 0.5, 1.0 and 1.5 ton/fed.). The experiments were performed in a split-split plot design with three replicates where, sunflower cultivars were assigned to the main plot, while nitrogen and filter mud cake rates were distributed randomly in the sub and sub-sub plot, respectively. The combined analysis was conducted across the two seasons.
The obtained results indicated that sunflower cultivars exhibited significant differences in all studied traits except harvest index. Plants of Sakha-53 were superior significantly than Giza-102 in all studied traits i.e., head weight and diameter, shelling %, no. of seeds/head, seed index, seed yield/plant, oil and protein percentage as well as seed and oil yields/fed.
Increasing the level of nitrogen applications up to 45 kg N/fed. caused highly significant increases in all traits under study except no. of seeds/head and shelling % which did not reach the level of significance. On the contrary, harvest index and seed oil percentage decreased significantly by increasing N levels up to 45 kg N/fed.
The application of FMC to sunflower plants exerted a significant influence on all traits under study except no. of seeds/head and harvest index which did not reach the level of significance. In general, head characters, seed yield/plant, seed index and protein % as well as seed and oil yields/fed. increased by increasing the rate of FMC applications while oil % decreased with increasing the rate of FMC applications.
In general, the highest yield/fed (seed & oil) was recorded by Sakha-53 (2336.43 and 1014.59 kg/fed.) when these plants received 45 kg N/fed. and 1.0 ton FMC/fed.