The effect of mycorrhiza on yield, oil content and water use efficiency of medicinal plant of Borage (Borago officinails L.) under water stress

Drought is one of the factors that affect medicinal plants and on the other hand, the role of mycorrhizal fungi was effective in improving the performance of some medicinal plants exposed to water stress. For this purpose, an experiment was conducted split-plot in randomized complete block design in the Boyerahmad region in three replications during years 2015 and 2016. The studied factors consisted of irrigation levels (primary factor) as irrigation after W1= 30, W2= 60, W3= 90, W4= 120 and W5= 150 mm water evaporation from evaporation pan class A and mycorrhiza fungi (sub-factor) at the levels of non application, application with Glomus mosseae species and application with Glomus intraradices species. Results of analysis of variance showed that the interaction between mycorrhizal fungi and water stress on grain yield, biological yield, 1000 grain weight, oil content and water use efficiency was significant at the level of 1%. In the treatment W30GM, the highest grain yield (276/5 kg/ha) and in the treatment W150NG, the lowest value of grain yield (69 kg) were obtained. In the treatment W30GM, the highest biological yield (5389 kg/ha) and in the treatment W150NG, the lowest value of biological yield (1517 kg/ha) were obtained. In the treatment W90GM, the highest seed oil percentage (29.38%) and in the treatment W150NG, the lowest value of seed oil percentage (14.97%) was obtained. In the treatment W90GM, the highest water use efficiency for grain (0.02460 kg/m3) and in the treatment W120NG, the lowest value of seed oil percent (0.01185 kg/m3) were obtained. Results showed that under water stress conditions, the use of mycorrhizal fungi could be effective in moderate water stress and increased grain yield, biological yield, grain weight, oil content and water use efficiency of borage compared to the control plants.