The effect of different combinations of biological fertilizer and different doses of chemical fertilizer on the severity of late blight on potato plants

Abstract Late blight disease is one of the problems faced by potato farmers. Chemical fertilizer and biological fertilizer (bio-fertilizer) reported have a potential to control late blight disease. However, there is a lack of research on the effect of combining the use of different types of bio-fertilizers with different doses of chemical fertilizers in potato plants to late blight disease. This study aims to analyze the effect of combining different types of bio-fertilizers and doses of chemical fertilizers on late blight disease in potato plants. This research was conducted from June to August in Sembalun District, West Nusa Tenggara Province. This study used fifteen combination treatments of bio-fertilizers and doses of chemical fertilizers. Each of these treatments included: A (control); B, C, D, E (bio-fertilizers, without chemical fertilizers); Treatment F, G, H, I (bio-fertilizers, chemical fertilizers 100%); J, K, L, M (bio-fertilizers, chemical fertilizers 50%); N (without bio-fertilizer, 100% chemical fertilizer) and O (without bio-fertilizer, chemical fertilizer 50%). The results showed that there was no significant difference in the effect of the combination of different bio-fertilizers and doses of chemical fertilizers on late blight severity.