84 Akta Agrosia. 2019. 22(2):84-94 Cited this as: Marwanto, S.P. Wati, A. Romeida, M. Handajaningsih, U. Siswanto, T. Adiprasetyo, B.G. Murcitro, and Hidayat. Bio-fortified compost as a substitute for chemical N fertilizer for growth, N accumulation, and yield of sweet corn. ISSN: 1410-3354 / e-ISSN:2615-7136 ARTICLE INFO Keywords: organic fertilizer, chemical fertilizer, bio-fortification, chemical fertilizer substitu- tion, bio-fortified compost Article history: Received: December 21, 2019 Accepted: January 6, 2020 Published: January 7, 2020 *Corresponding author: E-mail: marwanto@unib.ac.id ABSTRACT Finding the appropriate method of fertilizer application to simultane- ously enhance farm productivity and ensure ecosystem sustainability has been receiving a lot of attention. A field experiment was carried in the Research Plot Agriculture Faculty Bengkulu University Campus Indonesia in 2017. The purpose of this study was (1) to assess the sig- nificant effects of inorganic N fertilizer (IF) substitution with bio - fortified compost (BC) under equal N conditions on growth, N accumu- lation, and yield of sweet corn, and (2) to determine the appropriate lev- el to which inorganic N fertilizer could be reduced and equivalently replaced by bio-fortified compost to promote sweet corn growth and yield. The treatments consisted of six different proportions of inorganic N fertilizer (IF) substitution with bio-fortified compost (BC). Each treatment was designed on the basis of equal amount of total N input from a combination of both fertilizers (138 kg N ha -1 ). They were ar- ranged in a randomized block design with 3 replications. They included (1) 100% IF plus 0% BC, (2) 75% IF plus 25% BC, (3) 50% IF plus 50% BC, (4) 25% IF plus 75%, (5) 0% IF plus 100% BC, and (6) no IF and no BC. The results showed that the increasing proportion of IF re- placed by BC resulted in an increase for all variables (except for plant height) but they decreased when 100% IF substitution with 100% BC was applied. Among the partial substitution treatments, 50% IF plus 50% BC consistently produced the best growth, N accumulation, and yield increase. Treatments of 50% IF plus 50% BC and 25% IF plus 75% BC produced the highest green cob weight with husk per plot (10.74 – 10.84 kg plot -1 ), which was 16% to 19% higher than treatment of 100% IF plus % BC. The three partial substitution treatments pro- duced crop yield components as good as treatment of 100% IF plus 0% BC. Treatment of 0% IF plus 100% BC reduced plant growth, N accu- mulation, and crop yield and its components. The appropriate level to which IF could be reduced and equivalently replaced by BC was at the range of 25% to 75%. Hence, a suitable replacement of inorganic N fer- tilizer with bio-fortified compost is considered a reasoned way to simul- taneously increase crop yield and reduce environmental degradation. Akta Agrosia Bio-fortified Compost as A Substitute for Chemical N Fertilizer for Growth, N Accumulation, and Yield of Sweet Corn Marwanto Marwanto 1* , Shinta Puspita Wati 2 , Atra Romeida 1 , Merakati Handajaningsih 1 , Usman Siswanto 1 , Teguh Adiprasetyo 3 , Bambang Gonggo Murcitro 3 , and Hidayat Hidayat 4 1 Department of Agronomi, Faculty of Agriculture, University of Bengkulu, Indonesia 2 Department of Agronomi, Faculty of Agriculture, University of Bengkulu, Indonesia 3 Department of Soil Science, Faculty of Agriculture, University of Bengkulu, Indonesia 4 Departement of Animal Husbandry, Faculty of Agriculture, University of Bengkulu, Indonesia Jl. WR Supratman, Kandang Limun, Bengkulu 38120, Indonesia INTRODUCTION Sweet corn with the scientific name Zea mays (L.) saccharata Sturt is a specific maize variety that has tender, delicious and sugary kernels. These characteristics make it used much like a vegetable rather than as a cereal grain. Data issued by the Indonesian Ministry of Trade in 2016 revealed that national needs for sweet corn in 2015 extended to 4.1 million tons year -1 and became greater in 2016 to reach 5.2 million tons year -1 . The tremendous