Abstract: The relationship was investigated between hormone metabolism and growth inhibition of maize caused by zinc deficiency.Solution culture was used to study the changes of contents of tryptophan, auxin, gibberellin A3, gibberellin A4 and abscisic acid in maize under different levels of zinc.Tryptophan or auxin was added after zinc deficiency treatment in order to research the effects on maize under zinc deficiency.Both zinc deficiency and low-zinc resulted in the reduction of tryptophan and auxin, the sensitive genotypes reduced much more than the insensitive genotypes, also, the transport of auxin from aerial parts to root was baffled.In the early stage of zinc deficiency, the contents of abscisic acid and gibberellin A4 in stems and leaves increased in the insensitive genotypes while decreased in the sensitive genotypes,which maybe related to resistance and compensatory growth of plants.Meanwhile, the contents of gibberellin A3 increased in both two genotypes.The addition of both tryptophan and auxin could help the sensitive genotypes to recover from zinc deficiency, but had no effect on the insensitive genotypes.There was no consistent correlativity between growth and contents of auxin, gibberellin A3, gibberellin A4 and abscisic acid under zinc deficiency.The hormone levels which could be influenced by growth speed participated in the resistance regulation．

Key words: Zinc deficiency, Maize( Zea mays L． ), IAA, GA₃, GA₄, ABA

CLC Number: 

• Q945.78

• Q946.885