Abstract:
Low soil fertility is one of the major constraints that limit crop production in sub-Saharan African countries including Ethiopia. The major soil related constraints in the study area are low soil OM, low available P, S and low total N. Hence, the field experiment was done during 2018/19 cropping season to assess the effects of Mesorhizobium inoculant, P, and S on nodulation, growth, nutrient uptake and yield response of chickpea. The experiment was laid out in randomized complete block design (RCBD) with a factorial combination of Mesorhizobium inoculant (un-inoculated and inoculated), three levels of P (17, 34 and 51 kg/ha) and S (7, 14 and 21kg/ha) in three replication using Haberu chickpea variety. All plots have received a basal application of 19 kg N/ha uniformly. Mesorhizobium inoculant, P, and S were applied at planting directly to the soil. Mean separation was made using the Duncan multiple range test (DMRT) at 5% probability level. Analysis of variance showed that crop phenology, nodulation (nodule number and nodule dry weight), growth parameters (shoot dry weight, plant height and number of branches), yield and yield components and uptake of (N and P) were significantly affected by the treatments. The highest number (47.23) and dry weight (460 mg) of nodules per plant was found at the combined application of P (51 kg/ha) with Mesorhizobium inoculant. The highest grain yield (2202.33 kg/ha), total N uptake (71.41 kg/ha), and total P uptake (15.41kg/ha) were obtained at the application of P (51 kg/ha) with Mesorhizobium inoculant. The economic analysis revealed that the highest net return (38,699.9 ETB/ha) with a marginal rate of return of (7.9%) was obtained from the combined application of Mesorhizobium inoculant with 51 kg P/ha and 21 kg S/ha. Hence, it can be tentatively concluded that combined application 51 kg P/ha and 21 kg S/ha with inoculant is found to be an appropriate combination. However, since the experiment was conducted only for one season and one site, repeating the trial at different sites as well as in the same trial site at different seasons would be important in order to draw sound recommendation.
