Soil chemical properties and corn productivity as affected by application of different types of fertilizer and planting method in acid sulfate soil

Acid sulfate soil is use as an alternative in optimizing suboptimal land to achieve corn self-sufficiency. Balanced fertilization plays an important role in efforts to improve corn yields. This study aimed to determine the effect of planting methods and optimal dose of fertilization. This research was carried out in potential acid sulfate soils with B type overflow. This study was arranged in factorial Randomized Complete Block Design (RCBD) consist of 2 factors. The first factor was the planting method consist of Zigzag, Legowo and Conventional planting methods. The second factor was the fertilizer types comprising NPK phonska 450 kg ha^-1 + urea 300 kg ha^-1 + SP36 300 kg ha^-1, NPK mutiara 450 kg ha^-1 + urea 300 kg ha^-1 + SP36 300 kg ha^-1, Urea 450 kg ha^-1 + SP36 300 kg ha^-1 + KCl 300 kg ha^-1, and NPK phonska 300 kg ha^-1 + SP36 300 kg ha^-1. The results showed that the application of different types of fertilizer and planting methods could improve pH in all treatments from very acidic to acidic. pH, EC, and Eh of acid sulfate soils at 70 and 100 days after planting (dap) were not affected by the interaction between different types of fertilizer and planting methods. Total N content in Zigzag planting method was significantly lower compared to in Conventional planting methods. Meanwhile, available P increased to very high. The Exchangeable K content was only increased in the fertilizer treatment with the addition of KCl reaching a value of 0.42 cmol + kg^-1 at 30 dap. Zigzag planting method significantly increased corn yield to 31 higher than in Legowo planting method and 16 higher than in the Conventional planting method. The application of fertilizer with a mixture of KCl significantly increased corn yield to 26.25. Therefore, the Zigzag planting method and fertilizer with KCl mixture are recommended for corn cultivation in acid sulfate soils. © 2019 IOP Publishing Ltd. All rights reserved.