Effect of NPK fertilizer and soil amendments of soybean productivity in saline soil

Abstract

Salinity on agricultural land due to global warming occurs almost all over the world. Salinity stress was harmful to cultivated plants, including soybeans. Saline soils require the management of nutrients and water to reduce salt from the soil so that plants can grow optimally. This study aims to obtain effective doses of NPK fertilizers and soil amendments for soybean cultivation in saline soils. The research was conducted during the 2019 rainy and dry seasons in Lamongan and Tuban Regencies, East Java Province, Indonesia. The electrical conductivity (EC) of soil during the growing season was 5-12 dSm-1, with irrigation water was 6-7 dSm-1. The treatment consisted of NPK fertilizers, ameliorants: gypsum, manure, and straw mulch, which were arranged in a randomized block design and replicated 15 times. The results showed that the Anjasmoro variety of soybean productivity on saline in the Lamongan Regency during the rainy season was higher (90%) than in the Tuban Regency in the dry season. Application of NPK Fertilizer (46 kg N + 108 kg P2O5+ 60 kg K2O ha-1 + or 400 NPKS kg ha-1 with ameliorants (gypsum 1.5 t ha-1; manure 2.5-5.0 t ha-1 and straw mulch 3.5 t ha-1) have the potential to increase soybean yield up to 2 t ha-1 on saline soil.