Characterising the genetic control of quality attributes in Pak Choi Brassica rapa subsp. Chinensis (L.).

1. A molecular definition of assembled resources
CN Seeds have a large collection of Pak Choi germplasm used in their breeding programme. For this new project, we will supplement these resources with assembled B. rapa/ Pak Choi core collections and publicly available bi-parental populations held at JIC and Wageningen University. The first phase of this ICASE award will employ high-throughput Genotype-By-Sequencing to generate high-density genotype data aligned with the latest B. rapa genome assembly. These data will be used to explore population sub-structure and relationships between individuals, to establish a new phylogeny-based description of the genetic resources. Haplotypes will be defined across new and existing germplasm, providing a means to track introgressed segments, speed up creation of advanced backcross lines, and provide a means to define intellectual property within the company's portfolio.

2. Developing a pipeline for enhanced breeding
The assembled germplasm will be characterised for morphological traits key to varietal development and organoleptic quality, e.g., agronomic characters: plant shape, bolting habit (flowering time), stem cracking (base), suppleness; leaf quality: colour, wilting; post-harvest leaf yellowing. Mean phenotype data for these traits will be combined with new GBS SNP data to dissect the genetic regulation of these traits, define available allelic variation. These data will enable the efficient selection of germplasm and establish a new molecular breeding platform at CN Seeds.