Enhancement of soybean nodulation by seed treatment with non–thermal plasmas

PÉREZ-PIZÁ, MARÍA CECILIA; CEJAS, EZEQUIEL; ZILLI, CARLA; PREVOSTO, LEANDRO; MANCINELLI, BEATRIZ; SANTA-CRUZ, DIEGO; YANNARELLI, GUSTAVO; BALESTRASSE, KARINA

Scientific Reports

Nature

Año: 2020 vol. 10

Soybean (Glycine max (L.) Merrill) is one of the most important crops worldwide providing dietaryprotein and vegetable oil. Most of the nitrogen required by the crop is supplied through biologicalN2 fxation. Non-thermal plasma is a fast, economical, and environmental-friendly technology thatcan improve seed quality, plant growth, and crop yield. Soybean seeds were exposed to a dielectricbarrier discharge plasma operating at atmospheric pressure air with superimposed fows of O2 or N2 ascarrying gases. An arrangement of a thin phenolic sheet covered by polyester flms was employed asan insulating barrier. We focused on the ability of plasma to improve soybean nodulation and biologicalnitrogen fxation. The total number of nodules and their weight were signifcantly higher in plantsgrown from treated seeds than in control. Plasma treatments incremented 1.6 fold the nitrogenaseactivity in nodules, while leghaemoglobin content was increased two times, indicating that noduleswere fxing nitrogen more actively than control. Accordingly, the nitrogen content in nodules and theaerial part of plants increased by 64% and 23%, respectively. Our results were supported by biometricalparameters. The results suggested that diferent mechanisms are involved in soybean nodulationimprovement. Therefore, the root contents of isofavonoids, glutathione, auxin and cytokinin, andexpansin (GmEXP1) gene expression were determined. We consider this emerging technology is asuitable pre-sowing seed treatment.