Study of Asystasia gangetica (L.) T. Anderson as cover crop against soil water content in mature oil palm plantation

Abstract

Background and Objective: The study of cover crop in oil palm plantation is more emphasized on its function as soil and water conservation. Cover crop utilization is one of agronomic practice to protect soil surface from any damage caused by rainfall on to the soil surface. Rooting system of the cover crop is able to hold the rain water and in turn maintaining soil water content. This study is aimed to study the effect of Asystasia gangetica (A. gangetica) as cover crop in mature oil palm plantation toward soil water content. Materials and Methods: Research was conducted in mature oil palm plantation. The experiment was conducted by constructing 4×2 m experimental plot between rows of oil palm. The experiment consisted of 2 levels of treatment namely planting cover crop A. gangetica and without planting cover crop. It was repeated 3 times. Hydrological parameter data, precipitation, initial soil water content (SWC), SWC during the experiment at specified soil depth (10, 20, 30, 40 and 50 cm) were observed from each trial plot. Soil water content (SWC) was measured using a sensor that connected with GardSens. Results: The results showed that A. gangetica caused soil water dynamics at the depth 0-20 cm that was at rhizosphere of cover crop. This has a good impact on the water availability of oil palm especially in dry periods when the rate of rainfall less than 60 mm/month. Conclusion: It was concluded that cover crop was able to conserve rain water and increased the water infiltration into the soil. This indicates that cover crop was potentially used to maintain and improve the availability of water requirement for the oil palm plantation.