The Effect of Pistachio Waste Compost and Mycorrhizal Fungi on Vegetative Growth and Nutritional Status of Pistachio Seedlings in a Saline-Sodic Soil

Organic fertilizers and symbiotic fungi are very important in agriculture because of their special role as a link between soil and plant. Currently, large parts of the country's pistachio orchards are facing water and soil salinity crisis. In this study, the effect of processed pistachio waste compost at three levels (0, 10 and 15 kg per seedling) and mycorrhizal fungi at three levels (0, 100 and 200 g soil containing fungal spores per seedling) belonging to four species (Funneliformis mosseae, Rhizophahus intraradices, Glomus iranicus, Rhizophahus irregularis) on vegetative growth and leaf nutrients concentration of two pistachio cultivars of Akbari and Badami Zarand, with three replications (each replicate consisting of four seedlings) were investigated. This experiment was carried out as a factorial split-plot in randomized complete block design (RCBD) for two years (2017 and 2019) in the saline-sodic soil and water condition. The results showed that 15 kg of pistachio waste compost increased the concentrations of nitrogen, iron, zinc and manganese elements in the leaves by 4, 9.7, 8 and 12.1% compared to control, respectively. Also, the height, width and leaf area of seedling leaves increased by 9.6%, 11.8% and 2.8%, respectively, by applying of 15 kg of pistachio waste compost compared to the control. The maximum concentration of leaf iron (702.2 mg kg-1) was observed in the treatment of 200 g of fungi. In the treatment of 100 g of mycorrhiza, the concentrations of manganese, leaf area and height were the highest with 64.8 mg kg-1, 415.3 cm2 and 44.9 cm, respectively. The root colonization percentages were 35.1 and 27.2 in Akbari and Badami Zarand cultivars, respectively. Overall, 15 kg of pistachio waste compost along with 100 grams of mycorrhizal fungi can result in proper vegetative growth of pistachio seedlings the saline water and soil conditions.