Effects of Organic Conditioner Applications on Dehydrogenase Activity in Soils Having Different pH Levels

This study was carried out to determine the effects of rice husk compost, town waste compost and tobacco waste applications on soil dehydrogenase enzyme activity in soils having different pH levels under greenhouse conditions. Soil samples used in this study were taken from (0-20 cm) depth of soil surface of the fields around Samsun. Soil samples are moderately fine, fine and moderate in texture, acidic, neutral and alkaline in pH, low in salt content, low and moderate in organic matter level, low and high in lime content. In the study carried out in split plot experimental design, rice husk compost, town waste compost and tobacco waste were applied into soils at four doses (0, 2.5, 5.0 and 7.5%) with two replications. After a month of incubation period, plants were grown in prepared media. According to analyses and evaluation of the results, it was determined that applications of rice husk compost, town waste compost and tobacco waste into acidic (Tepecik), neutral (Kampüs) and alkaline (？etinkaya) soils increased dehydrogenase enzyme activity of soils. Tobacco waste in acidic Tepecik soil and town waste in alkaline ？etinkaya soil were more effective applications on dehydrogenase activity of soil. While dehydrogenase activity in acidic soil increased with increasing application dose, dehydrogenase activity in alkaline and neutral soils decreased with high organic waste application doses. It was observed that effectiveness of soil conditioner changed depend on acid, neutral or alkaline soil reaction status with application dose and material property of organic waste