Simpson, C. J. C. | Search bioRxiv

bioRxiv2024

Identifying Agronomic, Nutrition and Leaf Vein Quantitative Trait Loci in the Orphan Crop Gynandropsis gynandra

A sustainable food supply is vital for addressing the challenges of a growing global population and climate change. Gynandropsis gynandra, a nutritious C4 orphan crop native to Africa and Asia, thrives in low-input agricultural systems, making it a valuable candidate for future food security. This crop also serves as a model for studying C4 photosynthesis. However, research on its genetic improvement is limited. In this study, two mapping populations from diverse parental lines were used to identify Quantitative Trait Loci (QTL) linked to agronomically relevant traits like plant height, leaf area, flowering time, nutritional content, and photosynthesis. Fifteen QTL were identified, with two affecting both leaf size and flowering time across populations, which can be applied for marker assisted selection for crop improvement. Additionally, QTL linked to C4 photosynthesis provide insights into the genetic mechanisms behind this pathway. Overall, this research enhances the potential of G. gynandra as a climate-resilient crop. One sentence summaryLeveraging natural variation in Gynandropsis gynandra to identify QTL associated with important traits.

plant biology↗

bioRxiv2022

The genome of Gynandropsis gynandra provides insights into whole-genome duplications and the evolution of C4 photosynthesis in Cleomaceae

Gynandropsis gynandra (Cleomaceae) is a cosmopolitan leafy vegetable and medicinal plant, which has also been used as a model to study C4 photosynthesis due to its evolutionary proximity to Arabidopsis. Here, we present a high-quality genome sequence of G. gynandra, anchored onto 17 main super- scaffolds with a total length of 740 Mb, an N50 of 42 Mb and 30,933 well-supported gene models. The G. gynandra genome and previously released genomes of C3 relatives in the Cleomaceae and Brassicaceae make an excellent model for studying the role of genome evolution in the transition from C3 to C4 photosynthesis. We revealed that G. gynandra and its C3 relative Tarenaya hassleriana shared a whole-genome duplication event (Gg-), then an addition of a third genome (Th-, +1x) took place in T. hassleriana but not in G. gynandra. Analysis of syntenic copy number of C4 photosynthesis-related gene families indicates that G. gynandra generally retained more duplicated copies of these genes than C3 T. hassleriana, and also that the G. gynandra C4 genes might have been under positive selection pressure. Both whole-genome and single-gene duplication were found to contribute to the expansion of the aforementioned gene families in G. gynandra. Collectively, this study enhances our understanding of the impact of gene duplication and gene retention on the evolution of C4 photosynthesis in Cleomaceae.

plant biology↗