<span style="color: #222222;">Vice President M Venkaiah Naidu today paid tribute to legendary freedom fighter and the designer of India's national flag, Pingali Venkayya on his birth anniversary.<br />''<br />''In a tweet, Mr Naidu said, Pingali Venkayya was a polymath with interests in geology, education, agriculture and languages. He said, Our national flag is a symbol of our sovereignty, great history and culture.<br />''<br />''The Vice President said, the nation will always be grateful to the designer of the Tricolour, the pride and glory of our nation.</span><br />