Endogenous cytokinins mediate growth-stimulating and protective action of the HUMI preparation on wheat plants inoculated with Tilletia caries

Abstract

Humic substances (HS) and preparations created on their basis are known to be effective in growth stimulation and improvement of resistance and productivity of different plant species. We have revealed that the presowing semidry treatment of wheat seeds with preparation HUMI (NVP ‘BashIncom’, Ufa, Bashkortostan, Russia) promoted seedling growth and increased wheat yield. This effect is likely to be due to the shifts induced by HUMI in the hormonal system of plants associated with a 1.5-fold persistent accumulation of cytokinins (CKs) without any changes in the contents of indoleacetic acid (IAA) and abscisic acid (ABA). Meanwhile, presowing treatment with HUMI had a stabilizing effect on the state of the hormonal system in the course of ontogenesis of wheat inoculated with teliospores Tilletia caries. Obtained data about prevention of the decline in the cytokinin content in HUMI-treated infected wheat is fundamental in the implementation of immuno-stimulatory effect of HUMI resulting in the suppression of the growth and development of pathogens.

Keywords:

• humic acids
• HUMI
• abscisic acid
• indoleacetic acid
• cytokinins
• Tilletia caries
• Triticum aestivum L.

Acknowledgments

This research is supported by the Russian Foundation for Basic Research – Povoljie (project no. 11-04-97051).