Effect of micronutrients spraying and planting density on yield and yield components of red beans (Phaseolus vulgaris L.) at Karaj conditions

To evaluate the effects of micro-nutrients foliar application and plant density on two bean genotypes, an experiment was conducted in split factorial arrangement based on randomized complete block design with three replications at the research farm of College of Agriculture and Natural Resources, Tehran University in 2015. Foliar spraying in four levels (control (water), ferrous sulfate (2 g.L-1), zinc sulfate (2 g.L-1), and mixture of ferrous sulfate and zinc (2 g.L-1)) was the main factor and different levels of plant density (20, 30 and 40 plants per square meter) as well as two bean genotypes (varieties Akhtar and D81083 Line) were considered as sub-plot factors. The results showed that compared to control, foliar application increased 32.12 and 30.47% of grain yield in D81083 line and Akhtar cultivar, respectively. Simultaneous foliar application of iron and zinc micronutrient fertilizers significantly increased the studied traits in both genotypes. Akhtar cultivar did not show a significant difference in terms of grain yield between densities of 30 and 40 plants per square meter, but at the density of 30 plants per square meter, D81083 line had a higher yield than the other two densities. In general, the results showed that the highest grain yield was obtained from simultaneous foliar application of iron and zinc in D81083 line with a density of 30 plants per square meter.