Naidu, who was speaking at an event organised by his well-wishers to 'meet and greet him', however, said that such allegations were "inescapable in public life".
Congress leader Jairam Ramesh had recently alleged that in July 2014, the Telangana government had placed an order of Rs 271 crore without inviting tenders for the purchase of vehicles for the police from two car dealers - Harsha Toyota owned by Naidu's son and Himanshu Motors owned by Telangana chief minister's son.
"I have no knowledge on the business of my son. I don't know the intricacies. They gave a big statement that Telangana government had purchased this number of vehicles from Harsha Toyota," Naidu said.
"Those who are in mud, they cannot see somebody wearing a white shirt and dhoti. They try to stick (mud) on others. Then I asked for the first time (about the business)", he said.
Also Read
"I was surprised then. Those who have seen me for so long; those (party leaders) in Delhi might not know. Those here should have told them. That's how I maintained," he said.
Naidu said he had told his children not to get into politics and that he would not interfere in their business.
"I did not interfere in any way in the business of my son any day," he said.
On the questions over the trust run by his daughter, Naidu said it has been functioning for the last 16 years and that it does not accept funds from government.
"I asked yesterday (about the matter). (They) said we don't take foreign contributions and we felt, what will happen if notice is given as they will cancel because we don't take (foreign contributions)," he said.
The Union home ministry has given notices to 18 lakh people all over the country, including 5,900 companies for taking foreign contributions, seeking details as part of Modi government's efforts to cleanse the system, he said.
Notices are issued routinely for details and that they have also been sent to Indira Gandhi Pratishtan, he said.
Disclaimer: No Business Standard Journalist was involved in creation of this content