Adem, GD and Roy, SJ and Zhou, M and Bowman, JP and Shabala, S, Evaluating contribution of ionic, osmotic and oxidative stress components towards salinity tolerance in barley, BMC Plant Biology, 14 Article 113. ISSN 1471-2229 (2014) [Refereed Article]
Copyright 2014 The Authors-distributed under Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 2.0)
Background: Salinity tolerance is a physiologically multi-faceted trait attributed to multiple mechanisms. Three barley (Hordeum vulgare) varieties contrasting in their salinity tolerance were used to assess the relative contribution of ionic, osmotic and oxidative stress components towards overall salinity stress tolerance in this species, both at the whole-plant and cellular levels. In addition, transcriptional changes in the gene expression profile were studied for key genes mediating plant ionic and oxidative homeostasis (NHX; RBOH; SOD; AHA and GORK), to compare a contribution of transcriptional and post-translational factors towards the specific components of salinity tolerance.
Results: Our major findings are two-fold. First, plant tissue tolerance was a dominating component that has determined the overall plant responses to salinity, with root K+ retention ability and reduced sensitivity to stress-induced hydroxyl radical production being the main contributing tolerance mechanisms. Second, it was not possible to infer which cultivars were salinity tolerant based solely on expression profiling of candidate genes at one specific time point. For the genes studied and the time point selected that transcriptional changes in the expression of these specific genes had a small role for barley’s adaptive responses to salinity.
Conclusions: For better tissue tolerance, sodium sequestration, K+ retention and resistance to oxidative stress all appeared to be crucial. Because these traits are highly interrelated, it is suggested that a major progress in crop breeding for salinity tolerance can be achieved only if these complementary traits are targeted at the same time. This study also highlights the essentiality of post translational modifications in plant adaptive responses to salinity.
|Item Type:||Refereed Article|
|Keywords:||barley, salt tolerance, stomatal conductance, sodium sequestration, potassium retention, membrane potential, tissue specific responses, H+ -ATPase, reactive oxygen species, cytosolic ion homeostasis|
|Research Division:||Biological Sciences|
|Research Group:||Plant biology|
|Research Field:||Plant physiology|
|Objective Division:||Expanding Knowledge|
|Objective Group:||Expanding knowledge|
|Objective Field:||Expanding knowledge in the agricultural, food and veterinary sciences|
|UTAS Author:||Adem, GD (Mr Getnet Adem)|
|UTAS Author:||Zhou, M (Professor Meixue Zhou)|
|UTAS Author:||Bowman, JP (Associate Professor John Bowman)|
|UTAS Author:||Shabala, S (Professor Sergey Shabala)|
|Web of Science® Times Cited:||99|
|Deposited By:||Tasmanian Institute of Agriculture|
|Downloads:||399 View Download Statistics|
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