Analysis of lateral root growth in Arabidopsis in response to physiologically active auxin analogues

Abstract

The aim of this work was to investigate the formation and development of lateral roots in model trials onArabidopsis thalianaL. Heynh wild type (Col-0), thealf4-1mutant and its allele by applying the physiologically active auxin analogues IBA, IAA, TA-12 and TA-14.Differences were observed between thealf4-1mutant and its allele phenotype in the formation of lateral roots. The application of auxin analogues was unable to restore the formation of lateral roots in thealf4-1mutant. In some cases, under the impact of IBA (1 μM), a cluster of xylem cells was activated in the pericycle of the primary roots and lateral root primordia were formed. The auxin analogues induced the growth of primary roots in thealf4-1allele and the formation and growth of lateral roots. The impact of IBA (1 μM), TA-12 (1 mM) and IAA (1 μM) was particularly evident. The intense formation of lateral roots under the impact of IBA and TA-12 could be related with the ability of these compounds to intensify mitotic activity in the apical meristem cells of the lateral roots. New data were obtained, showing that IBA and other physiologically active auxin analogues can modify the root system architecture of the test-plantArabidopsis.