IMPACT OF PLANT AGE ON DEHYDROGENASE ACTIVITY OF SOIL IN OIL PALM (ELAEISGUINEENSIS JACQ.) PLANTATION SITES OF BUHCHANGPHAI, MIZORAM, INDIALalawmpuia and H. LalruatsangaAbstract The activity of dehydrogenases is one of the most frequently used biological parameters for the evaluation of soil quality. They are a potent factor in shaping the diversity of soil microorganism. Among all enzymes in the soil environment, dehydrogenases are one of the most important, and are used as an indicator of overall soil microbial activity (Quilchano and Marañon, 2002; Gu et al., 2009; Salazar et al., 2011). Establishment of Oil Palm Plantation provoke many statement which posses immense challenge, that mono cropping practice of Oil Palm (Elaeisguineensis Jacq.) Plantation could have an impact on the soil enzymatic activity and the research aim to study the status of soil Dehydrogenase Activity (DHA) in soil of different ages of plantation. The data were collected during late monsoon and study site was located at Buhchangphai. In the study site, weeding was done periodically near the main trunk. Soil from plantation managed with fertilizer and plantation free from fertilizer were analyzed separately. Soil samples were collected from palm avenue which represent plant age of 3, 5, 10 and 15 years old. Soil was sampled 0-15 cm depth from two plots P (1) 2m, P (2) 5m away from the main trunk. V method sampled soil was then brought to laboratory in insulated ice box for analysis. Soil type is mainly sandy loam to sandy clay loam. Dehydrogenase activity was determined using TTC reduction method (Casida, 1977). The result showed a significant decline in DHA as the Palm age increase, and P(1) having decrease DHA in comparison to P(2) in all the study sites. The reduction of enzyme activity in any agriculture land over time is a concern. The DHA were significantly reduced in soil of older plantation elsewhere and therefore further research in determining the reason of disruption in soil enzymatic activity is yet a big challenge. |