Soil acidity, high solubility of Al, Fe and S as well as low soil fertility are obstacles to rice production in acid sulphate soil. However, rice production can be increase by improving land quality through application of ameliorant. The study was carried out on acid sulphate soil in Banyu Urip Village, Banyuasin Regency, South Sumatra during wet season of 2020. The study aimed to determine the effect of ameliorant to rice production in acid sulphate soil. The study used Randomized Block Design with 6 replications. The ameliorant tested were P1 = control (without ameliorant), P2 = Dolomite [CaMg(CO3)2] (2 t.ha−1), P3 = Agricultural lime/Calcium Carbonate [CaCO3] (2 t.ha−1), P4 = Manure (2 t.ha−1), P5 = Biochar (5 t.ha−1), P6 = dolomite + manure + biochar (1/3 of each dose) and P7 = agricultural lime + manure + biochar (1/3 of each dose); in which Swampland Soil Test Kit was used to determine the ameliorant doses. The ameliorant was spread across the soil surface two weeks before planting, then mixed using hoe at the same time with the second tillage. Parameters observed were agronomic characteristics including plant growth and yield components. Results showed that the provision of ameliorant was able to increase plant growth and productivity of rice in acid sulphate soil. The highest productivity was found in treatment P7 (3.96 t.ha−1 dry unhusked grain) which applied combination of agricultural lime, manure, and biochar.

Identification of the advantages of hybrid maize lines is needed to support the increased production and development of maize in tidal fields. This study aimed to identify the agronomic characters and yield components of hybrid maize lines/varieties and their relationship with high yield and efficient fertilization in tidal fields.  The design used was a Split Plot with three replications. The Main Plot was a hybrid maize line/variety (L39/MR4, MGOLD/G8, G28/MGOLD, P27). The subplots were Composite Fertilizer with 2 measures, namely 600 kg/ha and 720 kg/ha. The fertilizers of Urea (50%), SP 36 and NPK (100%) were given at 10 days after planting (DAP). The remaining Urea was given at 30 DAP, 50% and 58.33% respectively in the Composite Fertilizer treatment of 600 kg/ha and 720 kg/ha. The technical culture applied was optimum tillage with the 70 cm x 25 cm spacing, the irrigation being carried out at D/DAP and 15 DAP, the optimal control on the weed and Plant Pest Organisms. The result showed that the number of rows/cobs was an alternative variable in identifying maize lines/varieties with high yield and efficient fertilization. This character was closely correlated with seed/ear weight (r = 0.94) and Grain Yield Efficiency Index/GYEI (r = 0.84). All Genotypes were nutrient efficient (GYEI > 1) except G28/MGOLD (IGYEI < 1). Another approach used to identify efficient fertilization lines/varieties was the variable percentage of yield reduction through regression equations with GYEI (y = - 0.0104 x + 1.0426).  The character of high number of rows/cob could be used as genetic material in plant breeding programs. The lines/varieties as a component of efficient technology and high productivity would contribute to increase production and development of maize in tidal fields.