Effects of salinity, Azosperlium and nanoparticles (zinc and silicon) on yield and some physiological traits of triticale (× Triticosecale Wittmak.)

Salinity is one of the most important environmental stresses that reduce the ‎growth and yield of crop plants. Application of biofertilizers increases yield and the resistance of plants ‎against various environmental stresses, such as salinity. Also, zinc plays an important role in protein ‎metabolism, photosynthetic activity and some physiological traits crop plants. Zinc deficiency is ‎recognized as a critical problem in‏ ‏plants, especially grown on saline conditions with high pH values. But, ‎recent researches have shown that a small amount of nutrients, particularly Zn applied by foliar spraying ‎can affect ability of plants to salinity stress. Silicon is also a complementary micronutrient for biological ‎systems and has an important physiological role in increasing resistance of plants against various ‎environmental stresses. The aim of this research was to investigate Azosperlium and nanoparticles (zinc ‎and silicon) effects on yield and some physiological traits of triticale under salinity stress.‎ This experiment was conducted as factorial based on randomized complete ‎design with three replications in greenhouse research of the Faculty of Agriculture and Natural Resources, ‎University of Mohaghegh Ardabili during 2022. Factors experimental were included salinity stress at three ‎levels (no application of salinity as control, application of 60, 120 mM salinity) by NaCl, application of ‎plant growth promoting rhizobacteria at two levels (no seed inoculation as control and seed inoculation ‎with Azospirillium) and foliar application of nanoparticles at four levels (foliar application with water as ‎control, foliar application of 0.8 g.L-1 nano Zn oxide, foliar application 50 mg.L-1 nano silicon, combined ‎foliar application of 0.4 g.L-1 of nano zn oxide and 25 mg.L-1 of nano silicon). ‎ The results showed that application of Azospirlium and foliar application of nano zn-silicon ‎oxide under no salinity condition increased chlorophyll index (49.24%), relative water content (59.82%), ‎stomata conductivity (57.6%), maximum fluorescence (52.77%), variable fluorescence (136.09%), ‎quantum yield (54.24%) and grain yield (47.23%) in comparison with of no application of PGPR and ‎nanoparticles under salinity 120 mM. But electrical conductivity and minimum fluorescence (54.6 and ‎‎49.15% respectively) decreased in comparison with no application of PGPR and nanoparticles under the ‎same of salinity level.‎ The results of this study showed that application of Azospirlium and foliar application of ‎nano Zn-silcon oxide can increase the grain yield of triticale at salinity mM due to improving fluorescence ‎indices and some physiological traits such as stomata conductivity, chlorophyll index and relative water ‎content. Therefore, application of plant growth promoting rhizobacteria and nanoparticles (Zn and Si) can ‎be suggested as an effective method for moderate the effects of salinity stress.‎