Evaluation of row spacing and microelements spraying on yield and some morphological traits of peppermint (Mentha piperita L.)

In order to evaluate row spacing and microelements spraying on yield and some morphological traits of peppermint، a split plot experiment was conducted based on randomized complete block design with four replications in Sari Agricultural Sciences and Natural Resources University during 2010-20. Three levels of row spacing (50 × 10، 50 × 20 and 50 × 30 cm) and two levels of microelements (no spraying and spraying) were evaluated on peppermint at two harvesting time. The results showed that the first harvesting had significant effect on plant height، oil yield and dry matter. Maximum oil yield (19. 1 lit. ha1) and dry matter (1121. 3 kg. ha-1) was obtained in the first harvesting time. Microelements had significant effect on wet matter (3321. 3 kg. ha-1)، dry matter (987. 7 kg. ha-1) and oil yield (19. 63 lit. ha-1). Maximum dry matter (1015. 5 kg. ha-1) and oil yield (20. 31 lit. ha-1) was obtained in (50 × 20 cm) row spacing with spraying. 50 × 20 cm row spacing with spraying recommended، because of maximum oil yield in peppermint.