Abstract: Primary roots and the first to fourth layers of secondary roots ofmaize(Zea mays)emerged during seedling stage,the fifth and the sixthlayers appeared from enlongation stage till boating stage,and the seventh layer and those above(i.e,aerial roots)emerged from boating stagetill tasseling stage.In eac

Key words: Maize root system, Absorption ability, Biomass yield, The relationship between root and above-ground