The Effectiveness of Heated and Acidified Volcanic Ash on Exchangable K, Ca, Mg of Soil, and Kcl Efficiency for Growth and Yield of Corn (Zea Mays L)

Abstract

Volcanic ash contains minerals rich in nutrients K, Ca, Mg, and others that can improve soil quality. K element of weathered volcanic ash minerals is expected to reduce the amount of using KCl fertilizer. This study aimed to investigate the effectiveness of the use of Mount Sinabung volcanic ash to increase the elements of K, Ca, Mg marginal soil, and the efficient use of KCl fertilizer on corn. This study designed using a factorial randomized block design consisting of two treatment factors and five replications. The first factor was soil, heated and acidified volcanic ash, i.e. soil without volcanic ash (AO), original volcanic ash+soil (AA), boiled volcanic ash around 100^oC+soil (PA), volcanic ash heated using oven by 100^oC+soil (PO), volcanic ash HCl+soil (AS). The second factor was KCl fertilizer consisting of three levels, 0.0, 2.5 and 5.0 g/polybag. The results showed that the chemical properties of soil, volcanic ash, heated and acidified volcanic ash such as pH value was acid, the concentrations of exchangeable-K, Ca, and Mg was low. The application of heated or acidified volcanic ash and KCl fertilizer in marginal soils did not increase of exchangeable-K, Ca, except exchangeable-Mg from small to medium. The use of heated and acidified volcanic ash did not interact significantly with all parameters of corn (plant height, leaf area, corncob length, number of rows per cob, the weight of seeds per cob, the weight of 1000 grains and root weight). Volcanic ash only significantly affected leaf area, while KCl fertilizer significantly affected all components of corn. The efficiency value of KCl fertilizer was higher than volcanic ash so that the use of KCl fertilizer was more efficient.