Effects of starter nitrogen and foliar ‌application with methanol on nodulation ‎and quantitative and qualitative yield of soybean (Glycine max L.) in ‎Moghan region ‌‎ ‎

In order to study the effects of starter nitrogen and foliar application with methanol on nodulation, grain filling components and quantitative and qualitative yield of soybean (Glycine max L.), an experiment was carried out as factorial based on randomized complete block design with three replications at the farm at Parsabad of Mogan from Ardabil province in 2022. Factors experimental were included application of methanol at three levels (foliar application with water as control, application 15 and 30 volume percent) and three levels of starter nitrogen (no application as control, application of 25 and 50 kg/ha) by urea. The highest rate of nitrogen application (50 kg/ha) increased the number of nodules per plant (139%), number of pod per plant (37%), harvest index (9%), grain filling period (8%), oleic acid, linoleic acid and linolenic acid (14.7, 16.3 and 20.6% respectively) in comparison with no application of starter nitrogen. Hovewer, there were no significant difference in oleic acid, linoleic acid and linolenic acid between 25 and 50 kg/ha starter nitrogen. Foliar application of 30 volume percent of methanol increased the number of nodules per plant (15.2%), number of pod per plant (47%), harvest index (12%) and grain filling period (5%) in comparison no foliar application of methanol. Also, the highest rate of starter nitrogen and methanol application increased dry weight of nodules per plant (26.2%), plant height (54.2%), number of grain per pod (109%), maximum of grain weight (45.3%), grain filling rate (14.1%), effective grain filling period (28%) and grain yield (61%) in comparison no application of starter nitrogen and methanol. In this study, it seems that application of 50 kg/ha starter nitrogen and foliar application of 30 volume percent of methanol can be suggested for improve of nodulation, grain yield and unsaturated fatty acids.