Yield of faba bean (Vicia faba L.) as affected by lime, mineral P, farmyard manure, compost and rhizobium in acid soil of Lay Gayint District, northwestern highlands of Ethiopia

Abstract

BackgroundSoil acidity with associated low nutrient availability is one of the major constraints to faba bean (Vicia faba L.) production on Ethiopian highlands. Integrated use of organic and inorganic amendments is believed to reduce soil acidity and improve crop production. Therefore, this field experiment was conducted with the objective of evaluating the effects of lime, mineral P, farmyard manure (FYM), compost and rhizobium in acid soil of Lay Gayint District, northwestern highlands of Ethiopia, in 2016–2017 main cropping season. The experiment comprised twenty sole and combined treatments arranged in a completely randomized block design with three replications.ResultsCombined application of 8 t FYM ha−1 + 30 kg P ha−1 + 3.6 t lime ha−1 significantly (P < 0.05) increased plant height, number of leaves and branches per plant, pod length, biological and straw yields. Grain per pod, grain yield and thousand grain weight were significantly (P < 0.05) increased with the application of 4 t FYM ha−1 + 15 kg P ha−1 + 7.2 t lime ha−1. This treatment resulted in 102% grain yield advantage over the control. The next higher grain yield advantage of 89% was achieved with 4 t FYM ha−1 + 15 kg P ha−1 + 3.6 t lime ha−1. Nodule number and nodule dry weight per plant were also improved due to 4 t FYM ha−1 + 15 kg P ha−1 + 7.2 t lime ha−1 application. Among sole treatments applied separately, 8 t FYM ha−1 was observed to be superior in all parameters considered followed by 7.2 t lime ha−1.ConclusionCombined application of 4 t FYM ha−1 + 15 kg P ha−1 + 3.2 t lime ha−1 could be suggested as effective amendment to improve the yield of faba bean and therefore contribute the effort to insure food security in strongly acid soils of the study area.