effect of organic fertilizers on growth properties nuterien absorption and essential oil yield ofmedicinal plant of Mentha spicata L)

Consumption of organic manures such as vermicompost and spent mushroom compost in a system based on organic agriculture beside to maintenance soil health improvement and yield of medicinal plant spearmint. Therefore، an Completely Randomized design experiment with four replication on Spearmint (Mentha spicata L) was conducted in Horticultural Department of Mohaghegh Ardabili University. Experimental treatments include different rate (control، 10، 20، 30، 40 and 50%) of cow manure vermicompost and washed and unwashed spent mushroom compost (SMC). The base medium (control treatment) was a mixture of 75% from cultivated farm soil and 25% of sand. Results revealed that replacement of vermicompost and spent mushroom compost in growth medium have significant effect on all vegetable such as fresh and dry weight، height، chlorophyll content and area surface of leaves and macro element of areal sections of spearmint. The highest value for vegetative growth detected in 30% and 40% washed spent mushroom compost and 10% vermicompost. As increase in substitution of organic fertilizer in medium of plant، nutrient content of spearmint increased. subsitution of vermicompost and spent mushroom compost improved uptake of nutrient by plant roots and increased of percent and yield of essential oil in spearmint in comparison to control.