Enhancing maize yield and fertilizer efficiency in tidal swamp lands by employing biostimulants

Abstract

Tidal swamp lands in Indonesia, despite their low productivity, hold significant potential for improving maize (Zea mays L.) cultivation and food security. Biostimulants derived from plants, animals, and plant growth-promoting rhizobacteria (PGPR) can enhance productivity and maize yields. Notably, rice husk ash (RHA), rich in silica, and golden apple snail (GAS; Pomacea canaliculata, Lamarck, 1822), containing amino acids, offer growth-promoting benefits. This study examines the impact of liquid RHA, GAS, and microbial inoculant (PGPR) on maize yield in acid sulphate soils from Barambai District, South Kalimantan, Indonesia. A randomized complete block design was used to test nine treatments, including a control (no NPK or biostimulants), full NPK, 75% NPK, and six biostimulant formulations (B1 to B6) combining RHA, GAS, and PGPR with 75% NPK. Biostimulants with more than 50% GAS extract significantly improved maize growth and yield while reducing NPK fertilizer use by 25%. Specifically, biostimulant formulations B1 (10% RHA, 80% GAS, 10% PGPR), B2 (20% RHA, 70% GAS, 10% PGPR), and B3 (30% RHA, 60% GAS, 10% PGPR), combined with 75% NPK, produced 126.0, 125.0, and 111.0 g plant-1, respectively, compared to 97.67 g plant-1 with full NPK. This suggests that biostimulants can reduce fertilizer use without sacrificing yield. The results highlight the role of amino acids in GAS extract for enhancing maize productivity. Biostimulants, particularly those rich in GAS extract, show promise in increasing maize grain yield and reducing reliance on inorganic fertilizers. Further field testing in real-world tidal swamps is needed to validate these findings.