Abstract
This study was designed to find correlations between the rates of phosphorous and essential oil extracted from anise, coriander and sweet fennel plants grow in arid regions. The highest essential oil contents (% ) and yield (ml plant -1 & liter plot-1) were recorded under the level of 75 kg P ha-1 with the values of 3.3 %, 0.3 ml plant -1 and 0.2 liter plot-1 (for anise); 0.6 %, 0.1 ml plant -1 and 0.1 liter plot-1 (for coriander); 2 %, 0.5 ml plant -1 and 0.3 liter plot-1 (for sweet fennel) compared with control and other treatments. An increase in the amount of phosphorous of the plants resulted in the enhanced accumulation of essential oil, as well as in a rise in the major constituent's concentration. Groups of essential oils were changed with various phosphorous levels.
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