heat, sun, and tomatoes

[ljp]

I can get degree days, corn heat units, and probably cumulative sunshine for my neighbourhood. Is there any research relating tomato growth to those measures? There is some degree day information available; but, it is tied into other studies. I think corn heat unit/tomato relationships would be more useful. Then for my purposes I think the cumulative sunshine, factors in the day length, because the length of the day should affect growth.