What to say in one-minute presentation of a poster in a scientific conference?
I've seen this before and it can work very well. 
Your only task in the one minute slot is to convince people that they should come and see your poster. Say what you've been doing and why it's interesting. You could use your abstract as a starting point but don't just read it out. Keep the slide really simple with the paper title and authors and a single, striking figure.