Abstract Detail

Functional Genetics/Genomics

Dowling, Caroline [1], Shi, Jiaqi [1], Schilling, Susanne [1], Melzer, Rainer [1].

It's Been a Long Day: Uncovering the genetic control of flowering in Cannabis sativa.

The timing of flowering is critical for plant reproductive success. Alterations in flowering time genes facilitated the domestication and dispersion of the world's major crops. To adapt a new crop to specific latitudinal lines and climatic conditions, the timing of flowering is one of the key traits requiring fine-tuning. Hemp (Cannabis sativa) is the ideal crop for a future, sustainable economy with diverse uses spanning textiles, biofuel, and medicine. However, given the historical prohibition of this species, an immense knowledge gap exists for the genetic underpinnings of various traits in hemp, including flowering time. Most hemp cultivars are short-day plants, meaning they only flower when the day length drops below 12-14 hours. However, photoperiod-insensitive cultivars also exist, in which flowering occurs after a defined number of days post-germination irrespective of the day length. To gain an insight into the genetic mechanisms underlying photoperiod-insensitivity, we conducted quantitative trait locus (QTL) analysis on a mapping population formed from a cross between a monoecious photoperiod-sensitive and a dioecious photoperiod-insensitive hemp cultivar. Flowering time was determined to be sex-linked, with male plants flowering earlier than female and monoecious plants. Trait mapping performed on multiple generations has revealed a large effect QTL controlling flowering. Bioinformatic analyses subsequently conducted on this locus identified a structural variant impacting a key candidate gene. Expression analysis performed on detailed developmental growth stages supports the role of this gene in the hemp floral transition. This research is accelerating the ongoing domestication of hemp by facilitating its adaptation to diverse climatic conditions and expanding cultivation to a wider geographic range. These results represent a crucial step towards elucidating the genetic architecture of the flowering time network in this fascinating crop.

1 - University College Dublin, School of Biology and Environmental Science, Belfield, Dublin 4, Ireland

Keywords:
QTL mapping
Cannabis sativa
genomics
flowering
Transcriptomics
adaptation.

Presentation Type: Poster
Number: PCG005
Abstract ID:670
Candidate for Awards:None