Title: The use of ethyl alcohol and phytohormones to quickly and safely stop dormancy of potato tubers

Financing institution: National Science Center

Implementation period: 2011-2014

Contractors: dr that. Sławomir Wróbel – project manager
dr hab. Jacek Kęsy – performer

Implementing unit: Department of Seed Science and Potato Protection IHAR-PIB in Bonin
Department of Plant Physiology and Molecular Biology UMK in Toruń

Project value: PLN 186,010

Purpose of research:

Assessment of the effect of ethyl alcohol, sucrose and phytohormones (gibberellic acid and kinetin) and the time of application of these agents on reducing the level of ABA in tubers and interrupting the rest of potato tubers and microbubbles of hard-growing varieties immediately after harvest.

Results achieved:

  • The use of ethyl alcohol significantly shortened the dormancy of potato tubers, except that this relationship was strongly dependent on the variety.
  • The use of gibberellin had the greatest impact on tuber dormancy, whereas kinetin does not seem to be of major importance in this respect.
  • Increasing the soaking time of tuber sections significantly increased the effectiveness of individual research combinations.
  • The most effective in stopping dormancy was the Standard 2 combination, which in addition to gibberellin also contained thiourea and daminoside, and that containing 4% ethyl alcohol, gibberellin and kinetin, in which tuber sections were soaked for 30 minutes.
  • In most of the tested samples, there was no clear correlation of the decrease in the level of abscisic acid (ABA) responsible for resting, under the influence of the used combinations of compounds. A relatively large divergence of ABA levels was observed within the variety in individual samples immediately after soaking.
  • The longer period of microbubble production (about 147 days) and the rest interruption delayed about 3 weeks after harvesting significantly increased the share of germinating tubers. A significant difference in the effectiveness of interruption of dormancy between the combinations was found only within the first 13 days of treatment of the microbubbers. Later, the differences were blurred and statistically insignificant, which means that the share of germinated microbubbles was at a similar level.
  • It was found that the lower ABA content did not facilitate germination at all, because most of this compound was in the microbulbs of the Gwiazda variety, which showed the fastest germination. The assessment of ABA content in microbubbers was markedly smaller than in the case of tuber sections, which is probably related to the size of the tissue analyzed.