Assessing How the Aluminum-Resistance Traits in Wheat and Rye Transfer to Hexaploid and Octoploid Triticale

Abstract

The mechanisms of aluminum (Al) resistance in wheat and rye involve the release of citrate and malate anions from the root apices. Many of the genes controlling these processes have been identified and their responses to Al treatment described in detail. This study investigated how the major Al resistance traits of wheat and rye are transferred to triticale (x Tritosecale Wittmack) which is a hybrid between wheat and rye. We generated octoploid and hexaploid triticale lines and compared them with the parental lines for their relative resistance to Al, organic anion efflux and expression of some of the genes encoding the transporters involved. We report that the strong Al resistance of rye was incompletely transferred to octoploid and hexaploid triticale. The wheat and rye parents contributed to the Al-resistance of octoploid triticale but the phenotypes were not additive. The Al resistance genes of hexaploid wheat, TaALMT1, and TaMATE1B, were more successfully expressed in octoploid triticale than the Al resistance genes in rye tested, ScALMT1 and ScFRDL2. This study demonstrates that an important stress-tolerance trait derived from hexaploid wheat was expressed in octoploid triticale. Since most commercial triticale lines are largely hexaploid types it would be beneficial to develop techniques to generate genetically-stable octoploid triticale material. This would enable other useful traits that are present in hexaploid but not tetraploid wheat, to be transferred to triticale.

Physiological and Transcriptomic Analyses Reveal Commonalities and Specificities in Wheat in Response to Aluminum and Manganese

“…Since RRL is a ratio of means, while the measured net root growth values (x) were not paired between control and stress groups, the mean value and standard derivation of RRG were calculated according to the following Equation [37]:…”

Induced Polyploidy: A Tool for Forage Species Improvement

“…), and diploid outcrossing species rye (Secale cereale L.), with the aim of combining the nutritional characteristics from wheat with drought and salinity stress tolerance, plus rust resistance from rye [90]. Aluminum tolerance of disomic hexaploid and octoploid triticale showed variable contribution of its parental species and could not be fully expressed in rye synthetic cultivars [91]. Chromosome set doubling in maize × teosinte hybrids improved biomass yield, tillering, and resistance to heat stress [16].…”

Scope of Whole Genome Duplication in Forages: A Plant Breeder Perspective

“…Triticale is a human-made species originating from the hybridization between tetraploid self-pollinated species wheat (Triticum durum), and diploid outcrossing species rye (Secale cereale), with the aim of combining the nutritional characteristics of wheat with drought and salinity stress tolerance, plus rust resistance of rye [73]. Aluminum tolerance of disomic hexaploid and octoploid triticale showed variable contribution of its parental species and could not be fully expressed in rye synthetic cultivars [74]. Chromosome set doubling in maize × teosinte hybrids improved biomass yield, tillering, and resistance to heat stress [16].…”