Effect of mycorrhizal fungi and foliar application of putrescine on some biochemical characteristics and biomass of basil (OcimumciliatumL.) in two different harvesting times

In order to investigate the effect of mycorrhizal fungi and foliar application of putrescine on some biochemical characteristics, essential oil content, and biomass of basil (Ocimumciliatum L.), a split plot in time experiment with three replications was performed based on a completely randomized design. Treatments included three levels of mycorrhizal fungi (control, Glomusmossea, and Glomusintraradicese) and three levels of putrescine (0, 1, and 2 mM) as main factors and two harvesting times as sub-factor. Results indicated that application of mycorrhizal fungi and putrescine influenced  the biochemical traits, fresh and dry biomass of aerial parts, and essential oil content of the plants. The highest amount of chlorophyll a and essential oil content were observed at G. mossea and 2 mM putrescine application in the first harvesting time. The highest amounts of chlorophyll b and carotenoid were obtained at G. intraradicese and 2 mM putrescine application in the first harvesting time. But with increasing the day time length and temperature, the amount of photosynthetic pigments in the second harvesting time decreased. The highest antioxidant activity and total phenolic content were observed in the treatment of G.intraradicese without putrescine spraying in the second harvesting time. The highest fresh and dry biomass of aerial parts were observed by applying G. mossea; but, no significant difference was observed between the two concentrations of  putrescine and only a significant increase was recorded in comparison with no putrescine treatment. Generally, applying both types of mycorrhizal fungi as biofertilizers with foliar application of 2mM putrescine could significantly improve the traits in this study.