Genetic Analysis of Plant Height, Coleoptile Length and their Relationships with Rht12 and Rht13 Genes in Wheat

In wheat (Triticumaestivum L.) production, deep sowing is beneficial in some regions subject to soil moisture deficits and deeply planted wheat with longer coleoptilescould be affectedless by post anthesis drought due to its ability to use water at deeper layers of soil.This study was conducted to determine the effects of the semi-dwarfing genes Rht12 and Rht13 on coleoptile length, plant height, and yield-related traits; to confirm the inheritance of Rht12 and Rht13 based on molecular markers; and to determine the possibility of obtaining short wheat genotypes with long coleoptiles.Two F₄ populations derived from the crosses Merj-5 (Rht12)x Scholar and Magsilva-15 (Rht13) x Scholar were used to measure coleoptile lengths, plant height and several other agronomic traits.Previously identified simple sequence repeat (SSR) markers were screened to detect the F₄ lines carrying the responsible dwarfing genes in each population. The mean values of plant height and 1000-kernel weight of the lines witheither of the two dwarfing genes were lower than the lines without any Rht genes. The results of marker regression analysis revealed that only the marker for Rht13 (Xwms577) had negative and significant effects for those two traits. The segregation of both markers (Xwmc410 and Xwms577) were fit a monogenic inheritance pattern for each F₄ population. Lines which combined short plant height and long coleoptile were obtained in both populations. Development of short wheat genotypes with longer coleoptiles could contribute to emergence of the plants and therefore it would be possibleto utilize deep soil water in post anthesis drought stress.