Influence of nicotianamine and iron supply on formation and elongation of adventitious roots in hypocotyl cuttings of the tomato mutant ‘chloronerva’ (Lycopersicon esculentum)

Abstract

The influence of nicotianamine (NA) on formation and elongation of adventitious roots in hypocotyls of de‐rooted NA‐less mutant seedlings of Lycopersicon esculentum Mill, was examined in relation to the iron supply [ferric N‐N'‐ethylenediaminedi‐(2‐hydroxyphenylacetate) (FEDDHA), ferric ethylenediaminetetracetate (FeEDTA), ferric N‐(2‐hydroxyethyl)‐ethylenediaminetriacetate (FeHEDTA, Fe‐citrate and FeCl3] in the nutrient solution. The initiation of root primordia in hypocotyl cuttings was independent of NA and occurred with about the same frequency in both, mutant and wild‐type. In the mutant the development of primordia to adventitious roots was blocked at all iron sources used, except FeEDTA. Addition of NA (5x 10−6 to 2 × 10−5M) to the rooting medium resulted in a fast growth of adventitious roots in mutant cuttings with all iron sources tested. Rooting of wild‐type cuttings was independent from NA application and iron sources. We suppose that NA is involved in the intracellular transport of iron. Its function is possibly linked with chelation of ferrous iron in the cell.