Author(s): Elham Mohammed Attia, Wael Ismail Mohamed and Emad Saleh Hamed

Abstract: In two successive seasons, 2018/2019 and 2019/2020, this experiment was conducted in sandy soil at Siwa Oasis, Egypt. The research was set to study the effect of some manure types on the yield of marjoram plants. The experiment involved applying four treatments (control, 24 m³ sheep manure/hectare, 24 m³ compost manure/hectare, and a combination of 12 m³ sheep manure and 12 m³ compost manure/hectare). The treatments were compared asa randomized complete block design. Results showed that all organic fertilizers significantly enhanced growth, herbage yield, and essential oil over control treatment. The soil amendment with sheep manure combined with compost manure was significantly superior to individual resources in improving growth and yield characteristics. The chief components of marjoram essential oil were cis-sabinene hydrate, 4-terpineol, α-terpinene, γ-terpinene, sabinene, and α-terpinolene. Different organic fertilizers greatly affected oil composition. Providing soil with sheep and compost manures gave rich oil in α and γ-terpinenes.