Cell wall reinforcement in potato periderm after potassium phosphite crop treatment

LOBATO M C; OLIVIERI F.P.; DALEO G.R.; ANDREU A. B.

Potato Research

Springer

Año: 2018 vol. 61 p. 19 - 29

0014-3065

Potato periderm is the outer tissue of tubers that protect them from pathogen and pest attack, dehydration and wounding during storage. It is of secondary origin and replaces the epidermis early during tuber development. The outer layers of periderm are formed by cells with suberized walls. Phosphite compounds (Phi) are inorganic salts from phosphorous acid that are efficient in protecting plants from biotic stress produced by different pathogens and also against UV-B radiation. The aim of the present work was to study the effect of Phi on post-harvest potato periderm by analyzing cell wall components and related enzymes. Potassium phosphite (KPhi) was applied to seed tubers and/or foliage, alone or combined with conventional fungicide and the experiments were carried out in the field. Observations of periderm sections showed increases in suberin and pectin depositions in tubers coming from KPhi treated plants.In addition, peroxidase activity also increased in this tissue. The activity of laccases and superoxide dismutase was measured in protein extract of periderm, and an increase due to KPhi treatment was detected. The results presented here suggest that,early KPhi treatment to seed tubers followed by foliage treatment, leads to better plant development which include the reinforcement of cell wall of periderm cells, which represents a benefit for future response to stresses.