Strategy to improve peanut development by application of biostimulant and inoculant under drought stress

FURLAN ANA; BIANUCCI ELIANA; SEQUEIRA, MICAELA; GIORDANO WALTER; CASTRO STELLA

Lima

Congreso; III CONFERENCIA IBEROAMERICANA DE INTERACCIONES BENEFICIOSAS PLANTA ? MICROORGANISMO ? MEDIO AMBIENTE (IBEMPA); 2017

Universidad Nacional Agraria La Molina

The symbiotic interaction between legumes and nitrogen-fixing bacteria is often affectedby abiotic stresses, within which drought is of concern. Drought-stressed plants have animpaired growth and nodulation, accumulate osmoprotectants such as proline and showoxidative stress symptoms. Therefore, many efforts have been devoted to contribute to theimprovement of inoculation practices and crop protection by biostimulant application.Thus, the objective of this work was to analyze the effect of the joint application of seedbiostimulant and inoculant on growth and nodulation of peanut exposed to drought stress,evaluating the role of the aminoacid proline in the redox metabolism. The biostimulantused was a complex mixture of organic substances and micronutrients, includingmolybdenum and cobalt; the inoculants were two reference strains, Bradyrhizobium sp.SEMIA6144 and Bradyrhizobium sp. C-145; and the peanut cultivar Granoleico, the mostused in Argentina. The results showed that the application of the biostimulant along withthe inoculation improved plant growth upon exposure to drought, since promoted thedevelopment of an extended radical system that would be beneficial in the stress situationby increasing the exploration surface of water sources. The strain Bradyrhizobium sp. C-145was more efficient in the nodulation process than Bradyrhizobium sp. SEMIA6144 and itsefficiency was increased when the biostimulant was added. Drought stress inducedoxidative damage in peanut plants, although those inoculated with Bradyrhizobium sp. C145 and treated with the biostimulant did not present alterations. The biostimulantinduced the higher production of proline, which would protect peanut plants from theoxidative stress generated upon drought stress in the peanut cultivar. Thus, the use of theBradyrhizobium sp. C-145 strain along with the biostimulant is recommended for peanutcultivation in arid regions.