Abstract

CUESTA, Graciela  and  MONDACA, Eduardo. Effect of an auxin-based bioregulator on growth of tomato seedlings. Rev. Chapingo Ser.Hortic [online]. 2014, vol.20, n.2, pp.215-222. ISSN 2007-4034.  https://doi.org/10.5154/r.rchsh.2014.01.001.

Production of tomato seedlings in trays has increased in recent years because protecting the root system in a ball reduces transplant shock, resulting in a higher plant survival rate and thus avoiding the need to replant. Greater root development favors establishment in the field because it promotes water and nutrient uptake. Since root production can be promoted by auxin action, the aim of this study was to evaluate the effect of an auxin-based bioregulator on the growth of tomato seedlings in trays. The trial was conducted in a commercial nursery in San Juan, Argentina. The AC 55 tomato cultivar was used. Trays with 126 cells, 36 cm³ per cell, were used. The bioregulator was a commercial formulation containing 0.12 % indole butyric acid and 0.004 % forchlorfenuron. Four concentrations of the product (1, 3, 5 and 7 ml·liter^-1) and a control were tested in a completely randomized design with 5 treatments and 4 replicates. Samples were taken at 26, 33, 40 and 47 days after sowing. The variables measured were root dry weight (RDW), aerial dry weight (ADW), stem length (SL), number of leaves larger than 1 cm (NL) and third leaf length (LL). Higher doses increased RDW by 36-39 % compared to the control. The regression between root dry weight and applied dose indicates there could be a response to higher doses. No effect on growth in the aerial part of the plant was observed.

Keywords : Solanum lycopersicon L.; bioregulator; root weight.