The roll of foliar application nano-fertilizers in modulating the negative effects of salt stress in quinoa

This experiment was conducted to investigate the effect of foliar application different nano-fertilizers on modulating negativeeffectsof salt stress on quinoa, in factorial experiment based on completely randomized design with three replications in the research farm of Urmia University in the pot during 2018. The first factor was salinity of irrigation water using (Lake Urmia water at three levels: 0, 16 and 32 dS/m and the second factor was nano-fertilizers at five levels: calcium, silicon, zinc, potassium and control (no foliar application). The results showed that salinity stress caused negative effects on all traits affecting quinoa growth. The highest decrease in traits was observed in salinity stress of 32 dS/m. Salinity stress of 32 and 16 dS/m compared to control decreased plant height (20 and 17%), inflorescence number (48 and 36%), root volume (44 and 40%), main root length (41 and 23%), root dry weight (68 and 30%), relative leaf water content (26 and 13%), chlorophyll index (15 and 7%) and 1000-seed weight (31 and 23%), respectively; but increased ionic leakage by 14 and 6%, respectively. Foliar application with nano-fertilizer compared to control increased the yield, yield components and morphological traits. The highest seed yield was obtained under optimum conditions and severe salinity stress (32 dS/m) by foliar application with nano-fertilizer of zinc and silicon, respectively. Under severe salinity stress, foliar application with nano-fertilizer of silicon compared to non-foliar application increased the dry weight of inflorescences, total dry weight and seed yield by 35%, 16% and 43%, respectively, and moderated the effects of salinity stress. Foliar application with nano-fertilizer via enhancing chlorophyll index, relative leaf water content and improving root characteristics, led to increase yield and seed yield components of quinoa. Therefore, it seems that foliar application of nano-fertilizers is suitable to improve the yield of quinoa especially in salinity stress conditions.