Efficiency of Integrated Nutrient Management to Improve Eggplant Production in Intercropping Systems

Eggplant is a vegetable that is widely cultivated in Indonesia. Fertilization is one of the most influential factors to increase eggplant productivity. The research to improve the eggplant productivity through the application of various nitrogen nutrient sources in an integrated nutrient management system and an intercropping system with cabbage was carried out from June to December 2019 in Wonorejo, Poncokusumo-Malang. The study was conducted using a randomized block design (RBD) with 21 treatments and was repeated 3 times. The treatments were D0 = Control (180 kg N) and (D1–D20), which were various combinations of inorganic N fertilizers, manure, and microbes (EM and PGPR). Observations included the number of leaves and stem diameter of eggplant, number of cabbage leaves, number of fruit per plant, fruit weight (per plant, per hectare, and per fruit), and Land Equivalent Ratio (LER), soil analysis before and after the research. The results showed that the combination of 75% inorganic fertilizer + 20–30 t·ha^-1 manure + 10–20 ml·l^-1 microbe (EM / PGPR) in the eggplant – cabbage intercropping system increased the growth and yield of eggplant, with fruit weights ranging 1.86–2.35 kg·plant^-1 or 40.88–53.17 t·ha^-1, and LER value was 1.94–2.04