Abstract
The introduction of reduced height (Rht) genes Rht-B1b and Rht-D1b led to impressive increases in wheat (Triticum aestivum L.) yields during the Green Revolution. In the present study, the dynamic elongation of peduncle in a set of near-isogenic lines (NILs) carrying different Rht alleles (Rht-B1b, Rht-D1b, Rht-B1c, Rht-D1b+Rht-B1b, and Rht-D1b+Rht-B1c) were investigated. The reduction of the final length of peduncle in NILs was dependent mainly on the elongation rate, which was reduced by Rht genes, during rapid elongation phase. Resin sections showed that Rht genes strongly reduced the cell extension in peduncle. The expression of expansin genes, which mediate cell wall loosening and leading to cell expansion, were analysed by using real-time quantitative PCR (qPCR). Among the 23 possible wheat expansin genes, 17 were expressed in the peduncle. The spatial distribution of expression was further analysed for five expansins that showed high expression levels in the peduncles of Rht lines. Compared to wild type plants, the incorporation of Rht-D1b allele decreased about 37 and 80% of the expression levels of ExpA7 and ExpA3 in elongation zone, respectively. The presence Rht-B1c dwarfing genes, however, produced 53% reduction in the expression level of ExpA7, and seriously decreased about 70% of ExpB9 expression. Although the expression levels of five genes exhibited variability among the lines, an expansin gene, ExpB2, showed its expression level highly associated with the cell elongation rate in peduncle of different Rht lines.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.