Developing a high-throughput phenotyping method for oxidative stress tolerance in barley roots.

Abstract

More than 20% of the world’s agricultural land is affected by salinity, resulting in multibillion-dollar penalties and jeopardising food security. While the recent progress in molecular technologies has significantly advanced plant breeding for salinity stress tolerance, accurate plant phenotyping remains a bottleneck of many breeding programs. We have recently shown the existence of a strong causal link between salinity and oxidative stress tolerance in cereals (wheat and barley). Using the microelectrode ion flux estimation (MIFE) method, we have also found a major QTL conferring ROS control of ion flux in roots that coincided with the major QTL for the overall salinity stress tolerance. These findings open new (previously unexplored) prospects of improving salinity tolerance by pyramiding this trait alongside with other (traditional) mechanisms. In this work, two high-throughput phenotyping methods—viability assay and root growth assay—were tested and assessed as a viable alternative to the (technically complicated) MIFE method using barley as a check species. In viability staining experiments, a dose-dependent H 2 O 2 -triggered loss of root cell viability was observed, with salt sensitive varieties showing significantly more damage to root cells. In the root growth assays, relative root length (RRL) was measured in plants grown in paper rolls under different H 2 O 2 concentrations. The biggest difference in RRL between contrasting varieties was observed for 1 mM H 2 O 2 treatment. Under these conditions, a significant negative correlation in the reduction in RRL and the overall salinity tolerance is reported. These findings offer plant breeders a convenient high throughput method to screen germplasm for oxidative stress tolerance, targeting root-based genes regulating ion homeostasis and thus conferring salinity stress tolerance in barley (and potentially other species).

Plant phenotyping relevance

オオムギ根の酸化ストレス耐性を評価する高スループット表現型解析法を開発・評価しており、表現型取得法が研究の中心です。

Code and data availability

The paper describes viability staining and root growth assays for barley oxidative stress phenotyping, but provides no public phenotype dataset, image repository, analysis code, or model. The data availability statement says 'Not applicable,' and the only supplement (Additional file 1) is a protocol flowchart, not a数据/

No evidence-backed public reproduction asset is currently recorded.