Predicting plant robustness from respiration traits – novel concepts and tools

Abstract

Respiration traits were identified as highly promising for predicting plant robustness. They are involved in ‘environmental plant plasticity’. In the presentation, the rational of proclaiming ‘plasticity’ per se  as selective criterion will be explained. New concepts and tools, such as calorespirometry, will be presented. Recent results obtained through applying this approach will be shown from diverse species.

Predicting temperature-dependent multi-stress tolerance and robustness in non-explored Triticeae by calorespirometry – a proposal

Abstract

Respiration traits allow calculating temperature-dependent carbon use efficiency and prediction of growth rates and biomass formation. While photosynthesis is responsible for capturing CO₂ , respiration critically manages the destiny of structurally integrated CO₂  by regulating use of energy and substances. The efficient interplay of normal and alternative respiration pathways determines plant performance upon permanently changing and interacting abiotic and biotic environment. Thus, respiration traits are central for yield stability based on multi-stress tolerance. While eudicots present two alternative oxidase gene – subfamilies, AOX1  and AOX2 , that interact efficiently together for growth regulation, monocots were reported to miss the AOX2 gene subfamily. However, we identified now that AOX2  had been present in ancient monocots and got obviously lost during evolution. This opens additional new perspectives for future breeding efforts on increased respiration efficiency in terms of adaptive growth regulation by gene editing in Triticeae.  Calorespirometry is useful as a functional mean for pre-breeding that can discriminate genetic differences in respiration traits. Although it was early suggested that the methodology could be helpful in breeding programs to improve temperature-dependent growth performance the concept had never been applied in global breeding or screening for robustness traits in wild material.

The methodology has been adjusted in our lab to a wide range of crops, among them important cereals and diverse vegetables. However, it is critical that the protocol for measuring respiration traits will be well-adjusted to the plant species by considering deep knowledge on the specific physiology and functional cell biology behind the final target trait for production. Basic concepts for application and modeling will be explained and first results on genotype-screening will be presented for wheat, barley, rye and carrot.

Genomics-based markers for temperature-dependent multi-stress tolerance and yield stability – early prediction by calorespirometry