The block reward was 50 btc when we hit $32 in June, and it was 50 when we touched $2 in December. The block reward has no impact on the price. It may however have an impact on miner profitability.
You cannot say for certain because the block reward was never 25. Certainly it is hard to surmise how it could affect price, but that will remain to be seen. If the market for btc slows down because miners are providing a constant stream of new coins, it almost certainly would affect price. It's basic economics.
To what degree, that remains to be seen.