Correlation between cell size and blackspot of potato tuber parenchyma tissue after storage

•The cell size and the blackspot susceptibility of tested varieties were different.•There is a correlation between blackspot after 6 months storage and cell size.•The tubers which have smaller cells show greater blackspot susceptibility.

Mechanical injuries are the main cause of damage and loss of quality of plant raw materials. Potatoes are susceptible to external and internal pressures, which cause bruising and fracture in soft tissues. The paper shows research concerning the relationship between geometrical parameters of the microstructure of potato tuber tissue and susceptibility of potatoes to blackspot damage after six months of storage. Twenty eight potato varieties from 2011 and 2012 crops in Poland were used in the experiment. The tubers had a similar size and shape. A TRSLM confocal microscope was used to study the microstructure of soft tissue in potato tubers and microscope images of the perimedullary zone of the tissue were analyzed.The study shows that there is a correlation between the size of perimedullary tissue cells in potato tubers and blackspot damage. Potato tubers with smaller cells of the perimedullary zone show higher susceptibility to blackspot damage, described by the blackspot index BIP, in comparison with potatoes with larger cells which were stored for six months.