Accelerating Wheat Breeding with High-Throughput Phenomics.

Next generation genotyping and phenotyping technologies can help accelerate crop breeding. However, the conventional phenotyping tools commonly used in breeding programs are low-throughput and labor intensive. We have developed and tested Unamnned Aerial Verhicle (UAV) based high-throughput phenotyping analysis pipeline to assess its feasibility in Kansas State and CIMMYT wheat breeding programs. The UAV was equipped with the latest multi-spectral imaging cameras. The standard operating protocols and analysis routines were evaluated. The plant height, lodging, and multi-spectral traits along with the genomic data were used to generate genomic prediction and association analysis. A novel UAV based lodging assessment method was tested on data collected during seasons 2015-16 and 2016-17. The UAV based digital lodging index performed at par with the visual measurements in terms of trait heritability (~0.5-0.7). The genome-wide prediction accuracies for crop lodging were 30-40% across years. Genome-wide association analysis identified QTL on chromosome 2A to be associated with lodging in wheat. However, these QTL explained only small fraction of total variation for lodging, suggesting a complex genetic architecture for lodging. Genomic prediction accuracies for plant height and multi-spectral traits will also be discussed. These UAV based quality phenotypes will facilitate more informed selection decisions and rapid genetic gains in breeding programs.