New Biostimulants Screening Method for Crop Seedlings under Water Deficit Stress

Biostimulants can be used in many crops growing under water deficit conditions at the seedling stage. This study tomato, Solanum lycopersicum L., seedlings commercial 150-cell trays as an experimental setup to reproduce mild drought stress effects. The method showed significant reductions growth and RGR (25%) after a seven-day experiment. Gas exchange parameters (Pn, Gs E) had significantly lower values (30–50%) than control seedlings. Stress-related metabolite, ABA, exhibited accumulation tomato (24 h), consistent with SINCED2 gene expression. Proline levels were twice high water-deficit treated seedlings, remaining this level until end of However, total carbohydrates Qualitative quantitative analysis suggested that using variable ‘seedling biomass accumulation’ could simplify methodology. Twelve different biostimulants assayed, implementing simplification, all them higher non-treated ones deficit. Among them, putrescine, spermine spermidine most effective. is adjustable biostimulant volumes (1, 3 5 mL; 1 mM BABA), no differences between treatments.