Potato (Solanum tuberosum L.) is the most important vegetable crop globally and is very susceptible to high ambient temperatures. Since heat stress causes the accumulation of reactive oxygen species (ROS), investigations regarding major enzymatic components of the antioxidative system are of the essence. Superoxide dismutases (SODs) represent the first line of defense against ROS but detailed in silico analysis and characterization of the potato SOD gene family have not been performed thus far. We have analyzed eight functional SOD genes, three StCuZnSODs, one StMnSOD, and four StFeSODs, annotated in the updated version of potato genome (Spud DB DM v6.1). The StSOD genes and their respective proteins were analyzed in silico to determine the exon-intron organization, splice variants, cis-regulatory promoter elements, conserved domains, signals for subcellular targeting, 3D-structures, and phylogenetic relations. Quantitative PCR analysis revealed higher induction of StCuZnSODs (the major potato SODs) and StFeSOD3 in thermotolerant cultivar Désirée than in thermosensitive Agria and Kennebec during long-term exposure to elevated temperature. StMnSOD was constitutively expressed, while expression of StFeSODs was cultivar-dependent. The effects of salicylic acid (10⁻⁵ M) on StSODs expression were minor. Our results provide the basis for further research on StSODs and their regulation in potato, particularly in response to elevated temperatures.

Aeroponics is a modern and soilless technology that is used for the efficient production of pre-basic seed potatoes, namely minitubers. This study aimed to evaluate the effects of the cultivar and type of planting material on the production of minitubers in the aeroponic facility in Guča, Serbia, at short, 7-day harvest intervals. Although aeroponic cultivation prolonged the vegetative cycle in all five investigated cultivars, the dynamics of minituber formation varied between genotypes. Two early maturing cultivars, Cleopatra and Sinora, quickly completed the vegetative cycle and formed a small number of minitubers, while the medium-late to late cultivars, Kennebec and Agria, steadily tuberized during the entire cultivation period in the aeroponic facility. The type of planting material affected the dynamics of minituber formation in three investigated cultivars. Sinora, Cleopatra, and Désirée’s plants of in vitro origin reached the final number of minitubers and the vines started senescing much earlier than plants of minituber origin. Kennebec and Agria plants of in vitro origin produced the largest number of minitubers (53.8–54.5) and showed the highest yield (9.8–10.5 kg m⁻²) during the cultivation period, while the heaviest minitubers were formed by Sinora plants of minituber origin (15.48 g). In addition, the temperature during pre-harvest periods significantly affected the number of tubers at harvests in Kennebec and Agria, and minituber mass in Désirée.

Potato is a globally important, highly heat-susceptible crop species. We investigated the effects of prolonged exposure to elevated temperatures and exogenous salicylic acid (SA) on microplant growth and heat-shock response (HSR) in three unrelated potato genotypes/cultivars. Long-term exposure to 29 °C (mild heat stress) caused a significant reduction in the number of surviving explants and shoot morphometric parameters in heat-sensitive genotypes, while exposure to 26 °C (warming) caused only a decline in shoot growth. Interestingly, 26 °C-temperature treatment stimulated root growth in some investigated genotypes, indicating a difference between favorable temperatures for potato shoot and root growth. SA showed a protective effect regarding potato shoot growth at 26 °C. At 29 °C, this effect was genotype-dependent. SA did not affect the number of roots and inhibited root elongation at all temperature treatments, indicating the difference between shoot and root responses to applied SA concentration. Although HSR is mainly considered rapid and short-lived, elevated transcript levels of most investigated HSFs and HSPs were detected after three weeks of heat stress. Besides, two StHSFs and StHSP21 showed elevated expression at 26 °C, indicating extreme potato heat-susceptibility and significance of HSR during prolonged warming. SA effects on HSFs and HSPs expression were minor and alterable.

Plant growing technology involves usage of complex agrotechnical operationsaimed at creating favorable conditions for plant growth and development, that is,for better exploitation of cultivar genetic potential. Effects of mulching with whiteand black polyethylene foil, and organic mulch (straw) were studied in three, dripirrigatedpotato cultivars: Carrera (early), Laura (medium early) and Agria(medium late). Treatments were arranged in a randomized complete block designwith four replications at the site of Zemun Polje, Serbia (44°88'N, 20°35'E, 79 ma.s.l.) in three consecutive years (2011–2013). Results obtained on the variantswith different mulch materials were compared with results attained on the plot withbare soil (control). The highest average number of tubers per plant was determinedin cv. Laura’s control variant (12.0), while the lowest average number of tuberswas determined in the cv. Agria with white mulch (8.2). The highest average tubermass (146.3 g) and total tuber yield (59.6 t ha-1) was determined in cv. Carrerasubjected to the straw mulch treatment. The lowest average tuber mass and tuberyield was found in the cv. Agria on the variant with black polyethylene foil (83 gand 27.8 t ha-1). The results obtained in our study indicate positive effect of thecombination of straw mulch and irrigation on the productivity of potato. Moderngrowing technology, which includes the regulation of temperature in the surfacesoil layer by combination of soil mulching, drip irrigation system, and the use ofadequate genotypes, can result in high potato yield.