EFFECT OF RETARDANTS ON THE BIOMETRIC CHARACTERISTICS OF WINTER WHEAT (TRITICUM AESTIVUM L.) STEMS

This paper presents the results of a study on the effect of three retardants on the length of the stem, ear internode and successive internodes, as well as on the mechanical properties and geometric features of the stem of winter wheat, i.e. inner and outer stem diameter, as well as stem wall thickness. The following retardants: Antywylegacz Plynny 675 SL, Moddus 250 EC and Cecefon 465 SL, were applied at the recommended rates and at rates reduced by 50 and 67% at the beginning of stem elongation (BBCH 31) or at the 2nd node stage (BBCH 32) of winter wheat. The study showed that the lengths of individual internodes, their outer diameters as well as the diameter and thickness of the 4th internode were most influenced by the growth regulators used at the highest rate. The diameter of the stem gradually decreased from the lower internodes towards the ear.