Fig 1. Comparison of the root and shoot dry weights and root/shoot ratio of maize varieties grown in China and western countries during maize growth.

V1-V12: the first—twelfth leaf emerged with ligule visible; VT: tasselling; R1: silking; R2: grain ‘blister’ stage; R3: milk; R4: dough; R5: dent visible; R6: physiological maturity. Unpaired data in the scatter plots were collected from 106 publications studying maize root growth in field experiments over the last 50 years.