A Peptide Extract of Hydrolyzed Amaranth Globulin Induces Growth and Immunological Response in Tomato and Maize Plants

Aims: Evaluate the effect in growth and defense activation of a peptide extract from hydrolyzed globulin of Amaranth in tomato and maize plants.

Study Design: Using different concentration of peptides we evaluated the physiological effect of peptide extract from amaranth in two different commercial crops.

Place and Duration of Study: Department of Biomacromolecules Chemistry at the Chemistry Institute UNAM, and Plant Pathology Lab, Escuela Nacional de Ciencias Biológicas, UNAM, duration 1 year.

Methodology: For evaluating the effect of peptide extract from globulin (GPE), tomato seeds were geminated in different concentration of GPE (10, 1 and 0.1 mg/mL), 5 seed per treatment were used, the effect of germination was observed for the length of epicotyl and stem development. Activation of plant innate immune response was tested using tomato leaf disc system (5 discs per treatment), tomato disc were exposed to 3 concentration of GPE, boiled bacteria P. syrinage pv. tomato and plant defense activator BTH for 15 minutes and analyzed with histochemistry detection for ROS. ROS were also quantified in laves of tomato plants treated with GPE, boiled bacteria and BTH, ROS were detected with DMPO using electronic paramagnetic resonance. To evaluate the protective effect in other plants, leaf blight system withHelminthosporium sp. was used to know the effect of GPE against fungi infection.

Results: GPE showed an improvement of seedling development at the concentration of 1 mg/mL, while innate immune response was induced after 15 minutes with the concentration of 1 and 0.1 mg/mL of GPE. This result also matched with the observed protection assay in a model infection system of leaf blight, showing protection of several blight development at 0.1 mg/mL.

Conclusions: The peptides derived from hydrolyzed globulin of Amaranthus hypochondriacus induce promotion in growth and develop of tomato, also innate defense in tomato leaves and in maize against fungi infections.