36 www.jinagri.com Tesema et al., 2021 Received: 21 October 2021 Accepted: 20 November 2021 Published: 31 December 2021 *Correspondence Merdikios Malla mmalla658@gmail.com Journal of Innovative Agriculture: 8(4) : 36-42, 2021 DOI: 10.37446/jinagri/rsa/8.4.2021.36-42 Research paper Evaluation of blended fertilizer type on improving the productivity of onion (Allium cepa L.) in Bena Tsemay district, Southwestern Ethiopia Genanaw Tesema, Merdikios Malla * , Atinafu Tunebo Southern Agricultural Research Institute, Jinka Agricultural Research Center, P.O. Box 96 Jinka, Ethiopia. Depleting of soil fertility, inappropriate and imbalanced fertilizer application including different blended fertilizers are among the most important factors that reduce the productivity of onion. Therefore, the study was conducted to evaluate the blended fertilizer type effect on improving the productivity of onion in Bena Tsemay District, Southwestern Ethiopia. The study was conducted in the 2018 and 2019 cropping season and laid out in RCBD following three replications with spacing of 10cm and 20cm between plants and rows respectively. Control, (38N + 46P2O5) kg ha -1 , (182NPS+125Urea) kg ha -1 , (191NPSB+125Urea) kg ha -1 and (204NPSZnB+125Urea) kg ha -1 treatments were used for the experiment. The full dose of blended and P fertilizers was applied at planting time and urea was applied in two splits. The result was revealed that application of 191 kg ha -1 NPS+125 kg ha -1 Urea resulted in the highest total (30590.28 kg ha -1 ) and marketable (28079 kg ha -1 ) bulb yield, while the lowest total (18043.98 kg ha -1 ) and marketable (15278 kg ha -1 ) bulb yield were recorded from the nil. Moreover, the highest net benefits of 425585.8 ETB ha -1 and economic returns of 1119.76% were obtained in response to the application of 191 kg ha -1 NPSB+125 kg ha -1 Urea. Application of 191 kg ha -1 NPSB + 125 kg ha -1 Urea gives 45.59% yield increment and 43.46% increment in economic return over the control. Therefore, the application of 191 kg ha -1 NPSB+125 kg ha -1 Urea was recommended for the study area and similar agro-ecologies. Further investigation should be done on plant nutrient uptake and nutrient use efficiency and bulb chemical composition. Key words: blended fertilizer, economic return, productivity, soil fertility INTRODUCTION Onion (Allium cepa L.) is a bulb crop belonging to the family Alliaceae. It is an essential bulb crop in Ethiopia and is taken in to consideration essential with inside the Ethiopian everyday diet. All the plant components are edible; specifically, the bulb is the maximum famous vegetable in stews. Onion is valued for its awesome pungency and shapes vital components for flavoring sorts of dishes, sauces, soup, sandwiches, and snacks as onion jewelry and famous over the