DefinePK

Abstract

Humic substances have many beneficial effects on soil and plant growth. The peat is an accumulation of partially decayed organic matter that can be used to isolate humic acid from it. The objective of this study was to prepare humic acid from peat soil and determine its effects on maize plant growth in order to consider their agricultural use as organic fertilizers. The isolation and purification of humic acid (potassium humate) from peat soil of Kuala Tatau (Sarawak, Malaysia) was performed in the Ddepartment of Land Management, Universiti Putra Malaysia. A glasshouse experiment was conducted to study the efficacy of prepared humic acid of peat soil (HAPS) by comparatively evaluating it with a commercial humic acid (HAC). Different levels of both humic acids were mixed with macro and micronutrients and applied on maize crop to observe their effect on growth and nutrient uptake in acid soil. There were eleven treatments with different combinations of HAPS and HAC. The positive effects of both humic acid sources were observed on the whole plant growth. The maximum plant height among all treatments was recorded in plots where HAPS along with NPK and CuSO4 were applied. The thickest stems and the highest number of leaves were recorded in the plants which received HAPS + NPK + CuSO4 + ZnSO4. The same trend was observed in the enhancement of total plant dry weight and root dry weight of maize plant. The highest yield was recorded in treatment 9 (HAPS +NPK+ CuSO4 + ZnSO4). Although both types of humic acid increased the crop yield, but HAPS gave significantly better results. This study highlighted that humic acid prepared from peat soil is a worthwhile practice with enormous benefits for soil and crops.