Efficiency of a Seedling Phenotyping Strategy to Support European Wheat Breeding Focusing on Leaf Rust Resistance

Abstract

Leaf rust resistance is of high importance for a sustainable European wheat production. The expression of known resistance genes starts at different developmental stages of wheat. Breeding for resistance can be supported by a fast, precise, and resource-saving phenotyping. The examination of detached leaf assays of juvenile plants inoculated under controlled conditions and phenotyped by a robotic- and computer-based, high-throughput system is a promising approach in this respect. Within this study, the validation of the phenotyping workflow was conducted based on a winter wheat set derived from Central Europe and examined at different plant developmental stages. Moderate Pearson correlations of 0.38–0.45 comparing leaf rust resistance of juvenile and adult plants were calculated and may be mainly due to different environmental conditions. Specially, the infection under controlled conditions was limited by the application of a single rust race at only one time point. Our results suggest that the diversification with respect to the applied rust race spectrum is promising to increase the consistency of detached leaf assays and the transferability of its results to the field.

Genome-Wide Screening of Broad-Spectrum Resistance to Leaf Rust (Puccinia triticina Eriks) in Spring Wheat (Triticum aestivum L.)

“…Therefore, selection of stable highly resistant genotypes could be done in this experiment. Similar degree of broad-sense heritability was reported previously for LR seedling resistance ( Gao et al, 2016 ; Beukert et al, 2021 ). Such high degree of broad-sense heritability promised with a genetic improvement for leaf rust resistance against a wide range of Pt populations.…”

Exploring the Genetic Variation of Stripe Rust Foliar and Head Infection in Egyptian Wheat as an Effect of Climate Change

“…However, the degree of broad-sense heritability for PstHI was lower than PstFI which suggested that PstHI is more affected by the environment. High degrees of wheat resistance to PstFI were reported previously [4,9,14,41,42].…”

Crop Improvement: Where Are We Now?

“…However, if resistance quantification performed in controlled conditions is to be of value, there must be a strong correlation between these data and true resistance in the field. In their study, Beukert et al [ 29 ] reported an approach aiming at identifying seedling leaf-rust resistance in European wheat elite lines, combining detached-leaf assay with high throughput screening with a robot (Macrobot platform). Even if correlation remained moderate (0.38–0.45) between in vitro assays and adult plant resistance, the results are promising and there is room to improve this approach, especially with regards to the diversification of rust strains.…”