there is a promotion in growth of tomato stem diameter and leaf area at 240 mg mL-1. This is probably because
this concentration promote the activity of some enzymes on tomato, thus promote tomato growth, the growth of tomato at 120 mg mL-1 and 480 mg mL-1 were similar with that in control. It illustrates that this concentration of garlic bulb crude extract would not harm the growth of tomato, and 240 mg mL-1 concentration of garlic bulb crude extract even could promote the growth.