effects of organic, chemical and biological fertilizers on crude protein, oil yields and fatty acids of black seed (nigella sativa l.)

in order to investigate the effects of organic, chemical and biological fertilizers on crude protein and oil yields and fatty acids composition in black seed (nigella sativa l.), a field experiment was conducted at agricultural research station of ferdowsi university of mashhad, iran, in 2009-2010. the experiment was arranged by using a complete randomized block design based on factorial arrangement with three replications and 12 treatments. the experimental treatments included fertilizer sources (vermi compost, urea fertilizer and control) as first factor and different biological fertilizers (nitroxin (including azotobacter sp. and azospirillum sp), mycorrhizae, biosulfur (including thiobacillus sp.) + sulfur and control (no biofertilizer)) as second factor. results showed that crude protein and oil yields of black seed in vermi compost were significantly higher than urea fertilizer. in addition, the biological fertilizer had no significant increasing effects on crude protein and oil yields, except biosulfur + sulfur. chemical analysis of black seeds showed a composition of 10.9% crude protein and 24.5% fat. linoleic (49.18%) and oleic acids (26.77%) was the major unsaturated while palmitic acid (12.68%) was the main saturated fatty acid.