Biological elicitors to enhance wound healing responses in cut potato tubers

Authors: CHINTHA, PRADEEPIKA - North Dakota State University; SARKAR, DIPAYAN - North Dakota State University; RAMAKRISHNA, RAMNARAIN - North Dakota State University; Dogramaci, Munevver; LULAI, EDWARD - Retired ARS Employee; SHETTY, KALIDAS - North Dakota State University

Submitted to: Scientia Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/11/2023
Publication Date: 5/16/2023
Citation: Chintha, P., Sarkar, D., Ramakrishna, R., Dogramaci, M., Lulai, E.C., Shetty, K. 2023. Biological elicitors to enhance wound healing responses in cut potato tubers. Scientia Horticulturae. https://doi.org/10.1016/j.scienta.2023.112152.
DOI: https://doi.org/10.1016/j.scienta.2023.112152

Interpretive Summary: The unintended wounding of potato tubers during harvesting, post-harvest handling, packing, and transporting is one of the most serious challenges facing the potato industry in the United States. Wounding and bruising of tubers may cause water loss, texture (skin) aberrations, untimely sprouting, increase susceptibility to bacterial and fungal diseases, and affect overall nutritional qualities. Current post-harvest management systems are not efficient to eliminate these wounding related losses of potato. Therefore, it is essential to develop safe and practical solutions to improve wound healing (WH) responses both in unintentionally bruised tubers and in cut tubers used as seed. In this study, we have tested the effectiveness of natural compounds (water-soluble chitosan or COS, and cranberry pulp residue) for improving WH responses using tuber sections of two common potato cultivars. Significant improvement in WH responses were observed in COS-treated tuber sections after four days of wounding. Higher accumulation of stress protective compounds was also found in COS treated tissues of potato tubers. The results of this study indicate that COS may be utilized as a cost-effective treatment to improve WH responses in cut and bruised tubers, which can be utilized by the potato industry, farmers, and stakeholders to increase the productivity of cut seed tubers as well as to minimize the post-harvest damages caused by unintended wounding.

Technical Abstract: Bruising and wounding of potato tubers is a serious post-harvest challenge, which causes significant economic losses to the potato industry (=$320 M/year in the United States). Therefore, improving wound healing (WH) responses of cut and bruised tubers is essential to counter tissue damage and to control subsequent infections and maintain higher tuber quality. The main objective of this study was to investigate the efficacy of natural elicitors, such as water-soluble chitosan oligosaccharide (COS 0.125 g L-1), and bioprocessed cranberry pomace (Nutri-Cran 0.125 g L-1) for improving WH responses in cut potato tubers. Certified seed potato tubers of cv. Russet Burbank and Russet Norkotah were targeted using a standardized disc model system for the WH response of cut tubers. The role of protective redox-linked and anabolic pentose phosphate pathway (PPP) was investigated as key steps for potentially improving WH responses and suberization processes in cut potato tubers after four days of wounding. Enhanced WH response in cut potato tubers with improved accumulation of suberin biopolymers (suberized cells) was observed in COS elicitor treated cut discs. Additionally, improved PPP-linked redox regulation with high glucose-6-phosphate dehydrogenase activity and higher soluble phenolic content was also observed in COS treated tissues. These results indicated that natural bioprocessed elicitors, such as COS, can be utilized to improve WH related metabolic responses, consequently to increase the efficiency and quality of cut seed tubers, as well as to counter the post-harvest damages caused by unintended wounding.