Abstract:

Background: In sustainable crop production focusing on high-value products, biostimulants have been gaining increasing importance, thus the hypothesis that plant biostimulants could contribute to improving new potatoes quality; Methods: The effects of the seaweed extracts Bio algeen S90 (Ascophyllum nodosum) and Kelpak SL (Ecklonia maxima), as well as the humic and fulvic acids in HumiPlant (leonardite extract) on the tuber quality of very early potato cultivars (‘Denar’, ‘Lord’, ‘Miłek’) were investigated. Potatoes were harvested 75 days after planting (the end of June); Results: The biostimulants did not affect dry matter, protein, total sugars, monosaccharides and sucrose or L-ascorbic acid content in new potatoes. Bio-algeen S90 increased the starch content in tubers of all potato cultivars tested, on average, by 4.8 g∙kg−1 compared with control treatment without biostimulant, whereas Kelpak SL and HumiPlant reduced nitrates content only in tubers of ‘Denar’ cultivar, on average, by 8.50 mg∙kg−1, and increased ascorbate-nitrate index (IAN) by 0.29. The biostimulants did not affect potato after-cooking darkening. Both the nutritional value of new potatoes and after-cooking darkening depended on the cultivar and weather conditions during the potato growing period to a great extent; Conclusions: Plant biostimulants slightly affected quality of new potatoes.

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