Vol. 4, Issue 1, Part A (2022)

A pot incubation experiment was conducted during the 2012-2013 season at Agricultural Research Directorate / Baghdad - Iraq. Sesbania plant residues were applied with three levels (0%, 1%, 1.5% and 2% w/w) while maintaining the soil moisture at field capacity limits to control the degree of decomposition and nutrient level at two periods (first period 2 months and the second period 4 months after added the Sesbania plant residues). The following season 2013-2014, a field experiment was carried out at Al-Latifia research station using randomized complete block design (RCBD). Sesbania plant residues incorporated into un up layer of soil at levels (0%, 1%, 1.5% and 2% w/w), barley crop was planted. The results of the incubation experiment showed an increase in organic carbon content by 45% and 50% at the treatment of 2% in the 1^st and 2^nd period respectively, compared to control treatment. As well as all of the available nutrients content in the soil increased at period one, while in the second period of incubation the same trend occurred, except for N, Cu and Zn the soil content of these nutrients decreased. The results of the field experiment showed an increase in grain yield of barley crop from 19% to 30% when adding of sesbania plant residues compared to control treatment. The results suggest the importance of using sesbania plants as green manure to enhance soil properties and increasing its productivity.