Jmeter database testing - JDBC sampler giving higher response time than PL/SQL developer console

I am using Apache JMeter for load testing SQL queries, Most of these queries are SELECT statements, When i run the queries in PLSQL Developer IDE the response time is like 1 - 1.5 seconds. same query with one thread and 2 seconds ramp-up period is taking 4-5 seconds. Am i doing any mistakes in configuring the JMeter? Any help would be appreciated.