Response of Improved Lentil ( Lens Culinaris Medik ) Varieties to Phosphorus Nutrition on Vertisols of West Showa, Central Highlands of Ethiopia

Identification of appropriate varieties and rates of phosphorus fertilizer for different sites are important agronomic practices to increase the productivity of lentil. A field experiment was conducted during the 2016 main cropping season to evaluate the performance of lentil varieties and their response to phosphorus application on vertisols of Ambo. Four Lentil varieties (Gudo, Alemtena, Teshale and EL-142) with four rates of phosphorus (0, 10, 20 and 30 kg/ha) were combined factorialy in randomized complete block design with three replications. Varieties were significantly varied in days to 50% flowering and 95% maturity, number of nodules, plant height and biological yields. Application of phosphorus rate was significantly affected days to emergency, days to 50% flowering, days to maturity, number of nodule per plant, nodule dry weight, nodule volume, number of primary and secondary branches, number of pods per plant, number of seeds per pod, thousand-seed weight, plant height, grain yield, biological yields and harvest index of lentil varieties. Significant interaction effects of varieties and Phosphorus rate was observed with respect to 50% flowering, biological yields, number of nodules per plant and plant height of lentil varieties. All varieties showed better performance on various growth and phenological characters in response to phosphorus application. Application of 20 kg P ha-1 was gave better yield and yield components of lentil. The highest net benefit of 72240 EB ha-1 with marginal rate of return of 1177% was obtained from application of 20 kg P ha-1, which was followed by 62706 and 55188 EB ha-1, and marginal rate of return 1445 and 243 % with application of 10 and 30 kg P ha-1, respectively. Therefore, application of 20 kg P ha-1 is recommended to sustain lentil production in vertisols of Ambo areas in central highlands of Ethiopia.