Investigation the effect of biochar and irrigation water salinity on yield indicators and protein percentage of quinoa in deficit irrigation conditions

This research was conducted with the aim of investigating the effects of salinity and biochar on quinoa plant in deficit irrigation conditions. The experiment was carried out in a factorial and completely randomized design with three replications in greenhouse conditions. The treatments include three irrigation water treatments (60, 80 and 100% of the water requirement, ), three biochar treatments (0, 2 and 4% by weight of potting soil, ) and three the water quality treatment was (1, 4, and 7 dS/m, ). From the time of planting until the establishment of seedlings, all the pots were fully irrigated with fresh water and up to the agricultural capacity. Then the pots were weighed every other day and at each level of biochar and salinity, the deficit irrigation to the level of humidity was calculated based on the changes in the pot's weight. At the end of the growing season, the seeds were harvested from the spike. The index parameters of leaf area, spike weight, seed yield, water consumption efficiency and seed protein percentage were measured carefully in each pot. . With the reduction of irrigation water, the amount of quantitative parameters and plant yield decreased. The use of biochar up to the level of 2 percent by weight of the soil increased the parameters. The use of biochar at the level of 2 and 4% by weight increased the seed protein by 23.5 and % 12.08 respectively, compared to the control treatment. there was no significant difference in yield between 2 and 4 dS/m salinity treatment and the percentage of seed protein in 4 dS/m salinity was higher than 2 dS/m, it is possible to use water with 4 dS/m salinity for quinoa irrigation.