INSTITUTO DE FISIOLOGIA VEGETAL
Unidad Ejecutora - UE
Analysis of early vigor in twenty modern cultivars of bread wheat (Triticum aestivum L.)
M.L. MAYDUP; CORINA, GRACIANO; E.A. TAMBUSSI
CROP & PASTURE SCIENCE
Lugar: Collingwood; Año: 2012
The fast development of leaf area in seedlings is a relevant trait in order to increase early resources acquisition. The use of semi-dwarf genotypes in wheat has decreased the early vigor of modern cultivars. We studied the early vigor of twenty cultivars cropped in Argentina and the main objectives were: (i) to analyse the genotypic variability in early vigor (ii) to study morphological traits that can be good indicators of early vigor, such as seed mass, leaf width and specific leaf area and (iii) to analyse if some aspects of biomass allocation in the seedling, such as dry weight allocated to root, implicates a penalty over the early vigor. Experiments with non-selected and selected by mass seeds were carried out in a greenhouse. In addition, a field trial was made in order to test the reliability of the greenhouse results. Seeds mass was the main parameter related with early vigor. However, results from the experiment with selected seed showed that seed mass per se explain only partially the early vigor of the cultivars, since significant correlation was observed between the seedling leaf area of each cultivar in both experiments. We observed high correlation between net assimilation rate (NAR) and the changes in the ranking of early vigor of the cultivars throughout the experiment. Root biomass of the seedling was positively correlated with leaf area, indicating that both traits were not mutually exclusive. We built simple models by multiple regressions, including some parameters easy to be measured, in order to estimate early vigor. We found that seed mass and width of leaves taken together showed better adjust than seed mass or leaf width considered as unique parameter. We found significant high correlation between early vigor of greenhouse and field experiments, thus, the screening under semi-controlled conditions may be feasible.