Investigations on tensile strength of rachilla and seed retention strength in spikelets of Festulolium braunii

Investigations were carried out in 2008–2009 to assess the rachilla tensile strength and seed retention strength in spikelets of various Festulolium braunii genotypes depending on their growth stages. The cultivars (Felopa, Sulino and Agula) and breeding materials were used. With the aid of a special testing machine, retention strength of successive flowers/kernels in spikelets as well as strength required to rachilla breaking of selected spikelets were determined. It was found that the examined Festulolium braunii genotypes were characterised by specificity regarding seed retention strength in spikelets. This biological feature was smaller for top flowers/kernels and increased with the movement down the spikelet. It was found that in the examined genotypes of Festulolium braunii the seed retention strength in spikelets in the analysed consecutive growth stages was smallest in spikelets situated in the upper part of the inflorescence and the highest in the lower part