摘要：This study aims to determine the effect of a combination of chemical fertilizers and biological fertilizers on the fruit yield of red chilies and the income obtained by farmers. The research was conducted on rainfed lowland land in Nagari Pariangan, Tanah Datar Regency, West Sumatra in September 2016 February 2017. The research design used a Randomized Block Design with 4 treatments and 6 replications. The treatments used were NPK fertilizer 750 kg/ha (A0, recommendation), NPK fertilizer 500 kg/ha+biological fertilizer 6 l/ha (A1), NPK fertilizer 750 kg/ha+biological fertilizer 6 l/ha (A2), and NPK fertilizer 1,250 kg/ha+biological fertilizer 6 l/ha (A3). The results showed that the application of NPK and biological fertilizers had a significant effect on the growth and yield of red chilies. The use of NPK fertilizer 750 kg/ha+biological fertilizer 6 l/ha gave the best results on plant height, fruit circumference and fruit yield. The highest fruit yield was 11.35 tonnes/ha, an increase of 31.52% compared to without application of biological fertilizers. The increase in chili yield decreased with the increase in the NPK dose (from 750 kg/ha to 1,250 kg/ha), which was an increase of 29.2% from the yield obtained at the recommended NPK dose (A0). The highest income obtained by farmers was IDR 88,286,200/ha, also obtained in the treatment of using NPK fertilizer 750 kg/ha+biological fertilizer 6 l/ha (A2), and the smallest profit was in the treatment of using NPK fertilizer 750 kg/ha without biological fertilizer, namely IDR 46,866,200/ha. Thus the optimal yield and benefits of red chilies are obtained from the use of efficient inputs by applying the NPK fertilizer technology innovation according to the recommendations plus the provision of biological fertilizers (NPK 750 kg/ha+biological fertilizer 6l/ha).
