Effect of water stress, chemical and organic fertilizers on yield and yield components of rosemary (Rosmarinus officinalis L.)

To improve crop productivity under water stress conditions, understanding the interaction between fertilizers and water stress is very important for the proper management of fertilizers consumption. The present study was aimed at investigating the impact of water stress, and chemical and organic fertilizers on yield and yield components of rosemary (Rosmarinus officinalis L.). The experiment was carried out in Ferdows, Iran in 2015 in the form of split plots based on a randomized complete block design. 50% and 80% of water requirements were allocated to the main plots. Five kinds of fertilizers including organic fertilizer before planting (F1), foliar application of Macromix Gold organic fertilizer (F2), NPK chemical fertilizer before planting (F3), and foliar application of NPK chemical fertilizer after planting (F4), and no fertilizer (control, F5) were allocated to subplots. Results indicate that in conditions of 80% water requirement, fertilizer treatments of F2 and F4, and in conditions of 50% water requirement, fertilizer treatment F4 had the highest percentage of essential oil (more than 2%). Concerning dry matter, in both conditions of 50% and 80% water requirement, all fertilizer treatments had more dry matter than the control. Results demonstrated that in terms of achieving the maximum percentage of essential oil in conditions of 80% of water requirement, only chemical fertilizer as a foliar application (F4) is recommended, but in the case of 50% of water requirement, foliar application of Macromix Gold organic fertilizer (F2) can be a suitable alternative to chemical fertilizer (F4). Considering the achievement of maximum dry matter in both 80% and 50% treatments, organic fertilizer before planting (F1) is an economically and environmentally appropriate treatment