Wheat lines, suffering structural rearrangements between wheat-1BS and rye-1RS chromosomes, display differential patterns of magnesium accumulation

GUALANO, LEONARDO; MORICONI, JORGE I.; TRANQUILLI, GABRIELA E.; SANTA MARIA G.E.

rosario

Congreso; XXXIV Reunión de la Sociedad Argentina de Fisiología Vegetal; 2023

SAFV

The structural rearrangements resulting from the recombination of the rye (Secale cereale) chromosome 1RS with chromosome 1BS of bread wheat (Triticum aestivum) determine relevant agronomic consequences. Two near isogenic lines derived from that recombination, designated as 1RS and 1RW, differ in a relatively small region of the short chromosome arm. We have recently reported that such rearrangements imply modifications in the dosage of genes, which confer notable differences in drought resistance in a way primarily associated to differential capacity for soil exploration by the roots. An emerging question from such work is whether or not those rearrangements also influence differentially the ionome of these lines. We performed two independent studies of the ionome which unveiled the existence of relevant differences between 1RS and 1RW lines in the distribution of magnesium (Mg) between the shoot and the root. Our work also revealed that such differences occur over a wide range of Mg supply, being them attributable to inequalities in the specific rates of absorption and translocation of this element. A detailed study of the movement of water through the apoplastic and non-apoplastic pathways of radial transport, by using a fluorescent dye, indicates a minimal contribution of the bypass flow in both lines, which converges in assigning the differences found in Mg translocation to non-apoplastic routes, particularly those involving transport processes operating on biological membranes. The analysis of a comparative study of the transcriptome, formerly done for an apical segment of the roots of RS and RW plants, suggests that, at least in this zone, notable differences would occur in the expression of genes that encode cation transporters.