Influence of Phosphorus Fertilizer Rates on Yield and Yield Components of Faba Bean (Vicia faba L.) Varieties in Lemu Bilbilo District of Arsi Zone, Southeastern Ethiopia

Faba bean production is a common practice in Lemu Bilbilo areas. However, faba bean productivity is affected and limited by poor soil fertility and lack of alternative technologies such as application of optimum phosphorus fertilizer for different faba bean varieties. In view of this, a field experiment was conducted on farmer’s field during the 2017 main cropping season at Lemu Bilbilo with the objectives to determine the response of faba bean varieties to different rates of P fertilizer and its influence on yield and yield components of faba bean varieties. The treatments include three faba bean varieties (Tumsa, Gebelcho and Dosha) and five phosphorus levels (0, 10, 20, 30 and 40 kg P ha-1) from Triple Super Phosphate. The experiment was laid out in a randomized complete blocked design with 3 x 5 factorial arrangements with three replications. Significantly (P<0 .05) higher plant height was recorded from Tumsa variety. Total productive tillers per plant, thousand seed weights, and harvest index and biomass yield of faba bean were significantly affected by main effect of varieties. Higher total productive tillers per plant (1.53) were obtained from application of 30 kg P ha-1. Higher plant height (153 cm), biomass yield (14158 kg ha-1) and grain yield (6323 kg ha-1) were obtained from application of 40 kg P ha-1. Application of 10, 20 and 30 kg P ha-1 gave marginal rate of return of 1404694 and 502% for faba bean production, which are well above the minimum acceptable rate of return. Therefore, application of 20 kg ha-1 of P with Tumsa, Gebelcho and Dosha faba bean varieties were proved to be productive and superior both in seed yield as well as economic advantage and recommended for faba bean production in Lemu Bilbilo area. Further study should be conducted in the future both over locations and years in order to give full recommendation for practical application.