Unveiling the genomic diversity of Australian Papaya germplasm for breeding advancement

October 17, 2025

The Crawford Fund’s Queensland Committee has again partnered with the TropAg International Agriculture Conference to assist 10 young researchers from developing countries attend and present their science at this international conference which will be held in Brisbane from 11-13 November 2025.

Successful conference scholarship candidates must be an Honours or Postgraduate student from a developing country who is currently studying at a Queensland tertiary institute, and they must be an author or co-author on a submitted TropAg 2025 Conference abstract.

In the lead-up to the conference we will be publishing short blog posts written by the young researchers about their work. Here is the latest blog. We have already featured the work of Adhera Sukmawijaya and Juel Datta.

By Leela Manoharan, Griffith University

Papaya is a vital tropical fruit crop that contributes significantly to nutrition,

livelihoods, and food security worldwide. However, papaya production faces challenges such as disease outbreaks, fruit quality issues, and environmental stress, all of which limit yield and profitability. Traditional breeding methods can take years to achieve improvement, especially when these traits are influenced by many genes and environmental conditions.

My PhD research focuses on using plant genomics to accelerate papaya improvement. I am developing genetic markers that could be utilised in marker-assisted and genomic selection of papaya. By genotyping the diverse papaya accessions, I aim to reveal the genetic diversity of the Australian papaya germplasm, which is currently limited.

Through Genome-Wide Association Studies (GWAS) and Quantitative Trait Locus (QTL) mapping of the segregating papaya population, I aim to uncover genes and genomic regions associated with key important agronomic traits related to plant vigour and fruit quality. Furthermore, it could be utilised to develop a genomic prediction model for future breeding programs. The goal is to integrate this knowledge into marker-assisted and genomic selection tools that can predict promising plants at an early stage, thereby significantly shortening breeding cycles. This approach will help breeders develop new papaya varieties that are tastier, more resilient, and better suited for the varied growing conditions of Australia.

Ultimately, my research contributes to a sustainable and competitive tropical fruit industry, where science, technology, and agriculture work in tandem to create a better future for both growers and consumers.