Does anyone know if you can top an autoflowering plant to promote branch growth? The strain in question is the Annapurna, it is more like a bush then most of the autoflowering plants.
Generally auto veg and flower so quickly you don't want to stress them at all. You want to plant and just let them do their thing. Some folks will LST them with good results. I wouldn't personally top an auto. The less you mess with it the better, at least that's been my experience.
fruitbat is right, it's not recommended to top an auto, the best you can do is let her grow.
Now, if you want to do it because of height restrictions or other reaons, you can, just try to do it as soon as possible, before pre-flowers show or during the first stage of flowering.