changing speed of animated uv texture in particle system?

How can I change the speed of animated uv texture in a particle system?Which one should I touch?

it is a combination between the local and world velocity settings.

I 'had changed the local and wold velosity,but it doesn’t affect on the uv animation speed.Anyone can help me?

sorry, didn’t read the question properly. I don’t think the particle renderer gives you that manual option. You might be able to access the animation components of the particle renderer with code though and manipulate the frame rate from there, I’m just guessing…