Anatomical and morphological stem structure for modern medium-sized, intensive varieties of soft spring wheat

Scientific Research Institute of Agriculture for Northern Trans-Ural Region - Branch of Federal State Institutions Federal Research Centre Tyumen Scientific Centre of Siberian Branch of the Russian Academy of Sciences. 2, Burlaki street, Moskowskiy, Tyumen district, 625501, Tyumen region, Russian Federation

^* Corresponding author: Timofeev_vn2010@mail.ru

Abstract

Medium-sized, lodging-resistant varieties differ from long-stemmed ones by a straw length of 14 cm and by 1.3-1.8 cm of the lower internodes. The shortest supporting internode in the Rang, Troll varieties (5.3-6.7 cm), thickened lower internodes in the Rang, Troll, Grekum 114 varieties (2=2.6-2.8 mm; 3= 3,0-3,2-3,4 mm). Apollo, Rank, and Graecum 114 (14.0-14.3 m²/cm) are marked with specific weight of the straw. In medium-sized varieties, there are more vascular-fibrous bundles in the lower internodes, the following are distinguished: Rang (44.9-46.2 pcs.), Grekum 114 (39.8-42.1), Phoebus (39.4-42.8 pcs.). The diameter of large fibrous vascular bundles is more pronounced in Grekum 114, Lerma Rofo, Chapola (141-144 microns). Varieties with an increased number of vascular fibrous bundles have smaller diameters, which contributes to the flexibility of their stems. Medium-ripened ones have a more complete thickness of the straw and sclerenchymatous ring - 2 m-node = 68-72-82 microns; 3 = 56-62 microns, in high-stemmed ones it is 63 microns and 48-50 microns. The conjugation of the number of vascular-fibrous bundles, their diameters with elements of stem morphology is positive – from a weak to medium degree, more pronounced in stem density (0.553-0.653), other conjugations are practically absent, which makes it possible to combine well-expressed anatomical features with optimal stem morphology parameters in the created genotypes.