Differences in the physiological responses of Rht13 and rht wheat lines to short-term osmotic stress

Yan, J. and Zhang, N. and Wang, X. and Zhang, S. (2020) Differences in the physiological responses of Rht13 and rht wheat lines to short-term osmotic stress. CEREAL RESEARCH COMMUNICATIONS, 48 (1). pp. 41-47. ISSN 0133-3720 (print), 1788-9170 (online)

Text CRC_48_41-47.pdf Restricted to Repository staff only Download (815kB)

Abstract

GA-insensitive dwarfng genes e.g. Rht-B1b and Rht-D1b have been widely used to reduce plant height, increase grain yield and improve harvest index values. GA-responsive dwarfng genes, such as Rht13, have potential for wheat improvement but are not used in commercial breeding. Here, a set of recombinant inbred lines (RILs) of varying height was developed from a cross of Rht13-containing Magnif M1 and Rht8-containing Jinmai 47. These RILs (Rht13 and rht) were used to evaluate the efects of Rht13 on wheat drought resistance under hydroponics conditions simulated by polyethylene glycol-6000 (10% PEG). Under osmotic stress, Rht13 seedlings showed signifcantly lower transpiration rates than rht lines. The Rht13 seedlings also had relatively higher photosynthetic rates and lower leaf water loss rates and higher leaf relative water content than rht lines. While investigating the reasons underlying these diferences, we found that the Rht13 lines’ root system could reduce the decrease in root hydraulic conductance (Lp) via osmotic adjustment and via modulating the expression of plasma membrane aquaporins (TaPIPs). Because of the reduced transpiration rate, severely reduced shoot water loss and improved water uptake ability of roots under short-term osmotic stress, the Rht13 seedlings maintained their overall water balance more efectively than did the rht seedlings. These fndings demonstrate that the dwarfng allele is a potential candidate for wheat breeding programs aiming to improve performance in arid and semi-arid regions.

Actions (login required)

Edit Item