Effect of the endophytic fungus, Serendipita indica on the morphological and biochemical characteristics of narcissus (Narcissus tazetta L.) in various culture substrate

Narcissus tazetta L. is very proper plant to grow outdoor. Southern of Iran such as Khuzestan are one of the most relevant areas of narcissus flower production. However, the applied soil texture needs improvement. In this research, a factorial experiment was performed based on a completely randomized plan with seven repeats to study effects of culture substrate improvement accompanied with the inoculation of endophytic fungus Serendipita indica on narcissus yield. Four culture substrates (100% field soil, 75% field soil+25% sand, 50% field soil+50% sand, and 25% field soil+75% sand) were used as first factor, and the fungus S.indica as the second factor. Based on the findings from the research, the inoculation with S.indica led to increase in the traits the diameter of the biggest flower (104%), number of florets (121%), flowering stem length (114%), (137%), total chlorophyll (118%), carotenoid content (113%), and a decrease in flowering stem diameter (84%), and guaiacol peroxidase activity (76%) compared to the control (no-inoculation). Also it was known that the culture substrate 75% field soil+25% sand had the most positive effect on the indices, the diameter of the biggest floret, number of florets, flowering stem length, vase-life, total chlorophyll content, and carotenoid content. The interaction of two factors indicated that the S.indica-inoculated culture substrates: 75% field soil+25% sand and 50% field soil + 50% sand were the best treatments for narcissus growing. In conclusion, it can be said that despite of moderately good growth of narcissus in the field soil of Khuzestan, it needs the addition of sand for more porosity to produce high-quality cut-flowers. Based on the results from the research, the inoculation with S.indica had more positive impact on narcissus vase-life than soil texture. Hence, the use of a culture substrate with 25% sand together with field soil and the fungus inoculation was found as a proper medium for narcissus cut-flower production. Also with next studies, it is suggested to focus on the effect of soil composition and fungal inoculation on the conservation of water and the reduction of salinity effect.