Application of manure and biofertilizer to improve soil properties and increase grain yield, essential oil and ω3 of purslane (Portulaca oleracea L.) under drought stress

Purslane (Portulaca oleracea L.) is globally known for its alpha-linolenic acid (omega(3)). To investigate the combined effect of nitrogen and mycorrhiza under water deficit stress on the agronomic traits of purslane, a factorial split experiment was conducted based on a randomized complete block design with three replications in a semi-arid region of Iran in 2015 and 2016. The main plots were the factorial combination of two irrigation conditions (non-stressed control and stressed condition: irrigation at 70 % and 50 % of field capacity (FC), respectively) and two treatments, namely control and inoculation with arbuscular mycorrhiza fungi (AMF, Rhizophagus irregularis). The subplots were comprised of unfertilized control, 100 % farmyard manure (8.5 Mg FYM ha(-1), sheep manure (50 %) and chicken manure (50 %)), 100 % N (120 kg urea ha(-1)), 75 % FYM and 25 % urea, 50 % FYM and 50 % urea, and 25 % FYM and 75 % urea. In the first and second years, the drought stress reduced AMF colonization (by 30.3 and 15.3 %), leaf phosphorous content (by 5.8 and 7.7 %) and grain yield (by 22.6 and 21.1 %) of purslane while leaf omega(3) increased (34.6 and 34.1 %). The AMF increased the phosphorous uptake, grain yield, leaf essential oil, leaf omega(3), and soil CEC. While reducing soil pH, application of nitrogen fertilizers enhanced soil organic carbon and leaf col It can be stipulated that a mixed nutrition system increases the quantitative and qualitative traits in the purslane vegetative organs, reduces the use of agricultural inputs, and enhances the health of edible vegetative of purslane and soil chemical properties.