Possibility of increasing early crop potato yield with foliar application of seaweed extracts and humic acids

Abstract

Under climate change conditions, biostimulants play an important role in plant adaptation to abiotic stress. This paper analyses the effect of the seaweed extracts Bio-algeen S90 (Ascophyllum nodosum) and Kelpak SL (Ecklonia maxima) and humic and fulvic acids HumiPlant (leonardite extract) on early crop potato yield and yield components. Three very early potato cultivars Denar, Lord and Miłek were tested. Biostimulants did not affect the number of tubers produced by potato plants but increased the tuber weight per plant and average tuber weight and, as a result, the tuber yield. The yield-increasing effect of biostimulants depended on the hydro- thermal conditions during potato growth. Bio-algeen S90 and Kelpak SL produced better results in a warm and very wet growing season, whereas HumiPlant produced better results in a year with lower air temperature and with drought periods during potato growth. The use of biostimulants in early crop potato culture assured higher yield under abiotic stress conditions, and also contributed to improving its marketable value by an increase in the productivity of the marketable-size tubers and, simultaneously, decreasing the share of large tubers with a diameter above 50 mm. The tested potato cultivars showed a similar response to the biostimulants applied.