Effect of biofertilizer and putrescine application on grain filling components and dry matter remobilization of triticale (Triticosecale Wittmack) under water limitation conditions

To study the effect of biofertilizer and putrescine application on grain filling components and dry matter remobilization of triticale (Triticosecale Wittmack) in water limitation conditions, an experiment was conducted as factorial in randomized complete block design with three replications at the research farm of faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran, in 2020. The experimental treatments were included irrigation in three levels (full irrigation as control, irrigation withholding at 50% of heading and booting stages as moderate and severe water limitation, respectively), application of biofertilizers in four levels (no application as control, application of vermicompost, application of Mycorrhiza, both application vermicompost and Mycorrhiza), and application of putrescine (water sprying as control, and foliar application of 0.4 and 0.8 mM putrescine). The results showed that co-application of vermicompost and mycorrhiza along with foliar application of 0.8 mM putrescine under full irrigation conditions decreased dry matter remobilization from stem (34.59%) and shoot (28.76%) and their contribution in grain yield (94.14 and 85.74%, respectively) compared to no application of biofertilizers and putrescine under irrigation withholding conditions at booting stage. Furthermore, co-application of vermicompost and mycorrhiza along with foliar application of 0.8 mM putrescine under full irrigation conditions increased root weight (62.11%), root volume (63.17%), current photosynthesis (85.53%) as well as contribution of current photosynthesis in grain yield (28.65%), grain filling period (20.37%) and grain yield (39.6%) compared to no application of biofertilizers and putrescine under irrigation withholding conditions at booting stage. Based on the results of this experiment, it seems that the application of biofertilizers and foliar application of putrescine can increase the grain yield of triticale under water limitation conditions by improving current photosynthesis and grain filling components.