Wheat Line "RYNO3936" Is Associated With Delayed Water Stress-Induced Leaf Senescence and Rapid Water-Deficit Stress Recovery

Marlon-Schylor L le Roux; N Francois V Burger; Maré Vlok; Karl J Kunert; Christopher A Cullis; Anna-Maria Botha

doi:10.3389/fpls.2020.01053

Wheat Line "RYNO3936" Is Associated With Delayed Water Stress-Induced Leaf Senescence and Rapid Water-Deficit Stress Recovery

Front Plant Sci. 2020 Jul 14:11:1053. doi: 10.3389/fpls.2020.01053. eCollection 2020.

Authors

Marlon-Schylor L le Roux¹, N Francois V Burger¹, Maré Vlok², Karl J Kunert³, Christopher A Cullis⁴, Anna-Maria Botha¹

Affiliations

¹ Department of Genetics, University of Stellenbosch, Stellenbosch, South Africa.
² Proteomics Unit, Central Analytical Facilities, University of Stellenbosch, Stellenbosch, South Africa.
³ Department of Plant and Soil Sciences, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.
⁴ Department of Biology, Case Western Reserve University, Cleveland, OH, United States.

Abstract

Random mutagenesis was applied to produce a new wheat mutant (RYNO3926) with superior characteristics regarding tolerance to water deficit stress induced at late booting stage. The mutant also displays rapid recovery from water stress conditions. Under water stress conditions mutant plants reached maturity faster and produced more seeds than its wild type wheat progenitor. Wild-type Tugela DN plants died within 7 days after induction of water stress induced at late booting stage, while mutant plants survived by maintaining a higher relative moisture content (RMC), increased total chlorophyll, and a higher photosynthesis rate and stomatal conductance. Analysis of the proteome of mutant plants revealed that they better regulate post-translational modification (SUMOylation) and have increased expression of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) proteins. Mutant plants also expressed unique proteins associated with dehydration tolerance including abscisic stress-ripening protein, cold induced protein, cold-responsive protein, dehydrin, Group 3 late embryogenesis, and a lipoprotein (LAlv9) belonging to the family of lipocalins. Overall, our results suggest that our new mutant RYNO3936 has a potential for inclusion in future breeding programs to improve drought tolerance under dryland conditions.

Keywords: LC-MS/MS; RuBisCO; chlorophyll fluorescence; drought; mutant wheat; photosynthesis; random mutagenesis.