TEHRAN (Reuters) - Polls opened on Friday for Iran's run-off parliamentary vote which is likely to have no impact on the firm control of conservatives after the disqualification of many reformists in the first round.

State radio reported polling stations opened their doors to voters at 8 a.m. (11:30 p.m. EDT Thursday) and are due to close at 6 p.m. (8:30 a.m. EDT), although this has been extended in past elections.

Conservatives won a majority of seats in the 290-member parliament in the first round of the election in March. Around 11 million eligible voters can cast their votes for 82 undecided seats.

Moderate opponents of President Mahmoud Ahmadinejad said the vote was unfair because the unelected Guardian Council, which filters candidates on their commitment to Islam and Iran's clerical system, barred many of them from running in March.

Reformists, who secured more than 30 seats in the first round, have called for a high turn out because it would give the opposition a bigger voice.

The new parliament will begin work in May.

(Additional reporting by Zahra Hosseinian)

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