Impact of Drought Exerted during Spike Development on Tillering, Yield Parameters and Grain Chemical Composition in Semi-Dwarf Barley Mutants Deficient in the Brassinosteroid Metabolism

Abstract

Drought is a major factor limiting plant development and negatively affecting crop yield. It was reported that mutants defective in the brassinosteroid (BR) metabolism from several species, including barley (Hordeum vulgare), show improved tolerance to drought during the vegetative phase of growth. Hence, semi-dwarf barley mutants defective in the BR metabolism may be regarded as an alternative in breeding programs. Occurrence of drought during spike development has a profound effect on yield. Thus, determining reaction of the semi-dwarf, BR-deficient barley mutants to drought during the reproductive phase is crucial. This study was conducted on barley Near-Isogenic Lines defective in the BR metabolism and the reference ‘Bowman’ cultivar. The experiments were performed under laboratory (optimal watering and drought) and field conditions. The following yield-related parameters were analyzed: total tillering, productive tillering, average grain weight per plant and per spike, as well as weight of 1000 seeds. Additionally, an analysis of chemical composition of grain was performed. The BR-insensitive BW312 line showed the highest values of the productive tillering and grain weight per plant under the drought conditions. Perturbations in the BR metabolism did not have any significant deteriorating effect on the contents of grain chemical ingredients.

Glycogen synthase kinases in model and crop plants – From negative regulators of brassinosteroid signaling to multifaceted hubs of various signaling pathways and modulators of plant reproduction and yield

“…These results indicate that also in non-cereal crops the genes encoding the GSK3 proteins may be regarded as target for genome editing which may result in development of high-yield cultivars with improved fruit quality (Figure 7). Moreover, taking into account importance of semi-dwarf varieties for cereal crop breeding (Dockter et al, 2014;Dockter and Hansson, 2015;Gruszka, 2020), the GSK gene homologs in cereal crops may be promising targets of genetic manipulation to produce semidwarf varieties which may become a powerful tools in future breeding programs, particularly in the face of global climate changes (Saidi et al, 2012;Gruszka et al, 2020b;Liu et al, 2021). Influence of GSKs on proteins participating in various developmental and reproduction-related processes (continuation).…”

Drought-induced molecular changes in crown of various barley phytohormone mutants

“… 19 In contrast, Northey et al 20 reported that a reduction in BRs content could improve plant tolerance to drought. Furthermore, Gruszka et al 21 demonstrated that barley mutants defective in BR biosynthesis and perception had higher grain weights per plant under drought stress than under control conditions.…”