Further Study Of ZFT Fragment Function And Effect Of Fe～(2+),Fe～(3+) On Maize Seedling

A cDNA fragment, obtained by RT桺CR from iron梔eficient Zea mays roots by Sun MM, was successfully cloned to pLJC桾l vector. The fragment which is 653bp was sequenced and proved to be a putative iron transporter gene in Zea mays. Total RNA was extracted from several kinds of maizes cultured with different iron sources Fe( 11 )桬DTA and ferric citrate ) and time respectively. The Northern blots were performed, using the putative iron transporter gene fragment as probe. But there were not any results. Zea mays L. Xiyu No. 3 cultured with different iron sources Fe(II)桬DTA and ferric citrate ) was used in this experiment to study the difference of the leaf photosynthetic pigment content, the root activity, the root and leaf ATPase activity, the iron absorption kinetics, peroxidase and cytochrome peroxidase isozyme electrophoresis. The results obtained from the studies showed that compared with maize cultured with ferric citrate, maize cultured with Fe( II )桬DTA had higher leaf photosynthetic pigment content, higher root and leaf ATPase activity. The root activities were not obvious difference betweeen them. The peroxidase and cytochrome peroxidase isozyme electrophoresis results showed the obvious difference between the maize roots cultured with Fe(lI)桬DTA and ferric citrate, but not between the maize leaves. The iron uptake rates of intact roots of the maizes cultured with Fe( 11 )桬DTA and ferric citrate were found to follow Michaeiis桵enten curve. The results showed that the maize cultured with Fe(H)桬DTA had higher affinity with iron ( smaller Km ) and greater iron absorption rate ( bigger ~ ) compared with the maize cultured with fcrric citrate.