The tribe Triticeae includes major cereal crops (bread wheat, durum wheat, triticale, barley and rye), as well as abundant forage and lawn grasses. Wheat and its wild related species possess numerous favourable genes for yield improvement, grain quality enhancement, biotic and abiotic stress resistance, and constitute a giant gene pool for wheat improvement. In recent years, significant progress on molecular characterization and functional analysis of elite genes in wheat and its related species have been achieved. In this paper, we review the cloned functional genes correlated with grain quality, biotic and abiotic stress resistance, photosystem and nutrition utilization in wheat and its related species.

Triticum turgidum ssp. dicoccon PI94668 and PI349045 were identified as containing null alleles at Glu-A1 and Glu-B1 loci in previous investigation. Sequencing of the respective HMW-GS genes Ax, Bx, Ay and By in both accessions indicated equal DNA lengths with gene silencing caused by 1 to 4 in-frame stop codon(s) in the open reading frames. Six synthetic hexaploid wheat lines were produced by crossing PI94668 or PI349045 with six Aegilops tauschii by spontaneous chromosome doubling of unreduced gametes. As expected, these amphiploids had three different HMW-GS: Dx 3.1^t + Dy11^*t, Dx2.1^t +10^t and Dx2^t + Dy12^t in Glu-D1 but double nulls in Glu-A1 and Glu-B1. Quality tests showed that most quality parameters in two T. turgidum ssp. dicoccon parents were very low due to the lack of HMW-GSs. However, incorporation of HMW-GS from Ae. tauschii in six synthetic hexaploid wheat lines significantly increased most quality related parameters. The potential values of these wheat lines in improving the quality of wheat are discussed.

MADS-box genes interact with TB1 to regulate plant organ morphogenesis. In rice, OsMADS57 interacts with OsTB1 to control OsD14 transcription. In this study, we aimed to determine the relationships among these genes in barley. We identified a natural mutant of HvTB1 (HvTB1x) formed by a C→A transition at position 230, which resulted in a premature stop codon. We cloned the HvMADS57 and HvD14 genes and studied their expression in the tb1 mutant. The results showed that tHvMADS57 is a MIKC^c-type MADS-box gene, and the expression levels of both HvMADS57 and HvD14 were significantly reduced in the tb1 mutant when compared to those in the wildtype gene. These results indicate that, HvMADS57 regulates plant growth and development by interacting with HvTB1 to suppress the transcription of HvD14 in barley which is similar to the relationships among the orthologs of these genes in rice.