Effect of Blended Fertilizer Types and Rates on Growth, Yield and Yield Components of Bread Wheat (Triticum aestivum L.) in Wondo District, Southern Ethiopia

– Soil fertility decline is one of the principal factors contributing to low productivity of crops and food insecurity in Ethiopia. The information available with regards to effect of blended fertilizer type and rates on growth and yield performance of bread wheat ( Triticum aestivum L.) for optimum production on loam soils of Wondo district is very limited. Therefore, a field experiment was conducted on loam soils of Wondo district Bachel Gigissa Peasant Association Farmers training center during 2018 cropping season to assess the effect of different blended fertilizer types and rates on growth, yield and yield components of bread wheat. The treatments studied consist of: control and three blended fertilizer formula NPS, NPSB, and NPSBZn each with four different rates (50, 100, 150 and 200 kg ha 1 ). Recommended rate of Urea (100 kg ha -1 ) was used equally for all treatments in spilt application and Danda’a variety was used as a test crop. The treatments were laid out in a Randomized Complete Block Design with three replications. Soil and crop data were collected and analyzed using the SAS statistical package program version 9.4 and LSD at 5% probability level was used to establish the difference among the means. The soil result revealed that the experimental soil site texture was classified as loam. The highest (30.06 kg -1 ) agronomic efficiency obtained from150 kg ha -1 NPSB. The results revealed that application of blended fertilizers (NPS, NPSB and NPSBZn) delayed days to flowering, and physiological maturity by (13, 9, 10) and (15, 14 and 11) days, respectively as compared to control plot. Leaf Area Index and Straw yield were significantly (p ≤ 0.01) affected by the application of different blended fertilizer rates and significantly (p ≤ 0.05) by the main effect of blended fertilizer types and interaction effect. Grains per spike and grain yield were significantly (p ≤ 0.01) affected due to the main effects of blended fertilizer types and rates, they were also significantly (p ≤ 0.05) affected due to the interaction effect. Above ground biomass was significantly (p ≤ 0.01) affected due to main effect of blended fertilizer rates and the interaction effect however, non-significant (p > 0.05) due to blended fertilizer types. This study also revealed that, blended fertilizer types and rates significantly (p≤0.05) affected DH, NFTm -2 , DPM, PH, SL and HI while TSW was significantly (p≤0.05) affected only by the main effect of blended fertilizer rates. Blended fertilizers had improved Agronomic nutrient use efficiency of wheat as compared to the control treatment. The highest (6.17t ha -1 ) grain yield was obtained from 200 kg ha -1 NPSB +100 kg ha -1 urea application followed by (6.11 t ha -1 ) from 150 kg ha -1 NPSB + 100 kg ha -1 urea, while minimum (1.95t ha -1 ) grain yield was attained from the control treatment. However, the application of 150 kg ha -1 NPSB + 100 kg ha -1 urea had highest marginal rate of return (MRR %) and Net benefit. Therefore, it would be advisable to use blended fertilizer 150 kg ha -1 NPSB + 100 kg ha -1 , for wheat production in Wondo area. Furthermore, based on yield, net benefit and relatively low total cost of production the farmers of Wondo area also can use 100 kg ha -1 NPSB+ 100 kg ha -1 urea. However, since the experiment was conducted only for one season and one site, repeating the trial at different site as well as in the same experimental site would be important in order to draw sound recommendation.