Induction of Phytoalexins Gliceoline and Proteins Related to Defense in Soybean Cotyledon Treated With Yeast

Yeasts can induce mechanisms of plant resistance due to compounds with eliciting characteristics, so the aim of this work was to evaluate the effect of yeast on the induction of phytoalexins gliceoline, peroxidase, polyphenoloxidase and phenylalanine ammonia-lyase from soy cotyledons. To determine the defense enzymes, soybean seeds were sown and the cotyledons treated with sterile distilled water, Cryptococcus laurentii (AH 03-1), Pichia guilliermondii (AH 16-2), Rhodotorula glutinis (AH 14-3), Sporidiobolus johnsonii (AH 16-1) and Zygoascus hellenicus (AH 14-1). Biochemical analyzes of the formation of phytoalexins and the activity of the enzymes peroxidase, polyphenoloxidase, phenylalanine ammonia-lyase and total proteins were performed. For phytoalexins glycerolins the yeasts Cryptococcus laurentii (AH 03-1) and Zygoascus hellenicus (AH 14-1) promoted an increase of 83.65% and 78.75% in the formation of this compound. Cryptococcus laurentii (AH 03-1) increased peroxidase activity by 36.84%, while for polyphenoloxidase, the Pichiaguilliermondii e yeasts (AH 16-2), Rhodotorula glutinis (AH 14-3), Sporidiobolus johnsonii (AH 16-1) and Zygoascus hellenicus (AH 14-1), increased the activity of this enzyme by 33.33%, 28.00%, 33.33% and 33.33%, respectively. For phenylalanine ammonia-lyase, Cryptococcus laurentii (AH 03-1) and Zygoascushellenicus (AH 14-1) promoted an increase of 75.57% and 78.86%, respectively, in their activity. The results demonstrate the potential of yeasts studied in the induction of phytoalexins glyceolins and in the activity of peroxidase, polyphenoloxidase and phenylalanine ammonia-lyase in soybean cotyledons.