The youth also waived black jacket towards Joshi as a mark of protest, police said.
Left stunned by the sudden happening, the organisers, managed to bring the protester down and later handed him to police.
Claiming to be "dedicated" a party worker, the youth, however, said he was "very hurt" with party's stand over the issue, and accused it of adopting "double standards" by supporting the bill.
Following disruption, the programme was stopped and Joshi's scheduled press conference was called off.
The BJP leader later refused to answer queries regarding differences in the party over the issue.
Earlier, the agitating state government employees, who were on a strike against the bill, had staged protest outside BJP office in the capital for supporting the quota bill in the Upper House of Parliament.
