Australia
May 15, 2025
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Members of the team that is diversifying sowing time options in legumes (left to right): Jakob Butler, Jim Weller, Laura James and Raul Ortega.
Photo: Jacqueline Vander Schoor
Tools are being developed to better understand the genetic basis of flowering time and phenology traits in lentils
Sowing and maturity times have become important levers that growers can use to optimise yield potential and yield resilience. Variation in these traits helps to make the best use of stored soil moisture and avoid heat, drought and frost stresses.
Making use of these levers in pulses, however, requires an influx of novel genetic diversity to provide wider variation in flowering time and reproductive phenology as well as an understanding of interactions with environment and management practices.
Efforts to exploit diversity in phenology traits in legumes are underway, with a starting focus on chickpeas and lentils. Photo: Jacqueline Vander Schoor
Associate Professor James Weller of the University of Tasmania is defining and characterising genetic variation in these important phenology traits.
The project, supported by GRDC investment, is developing the tools and information that breeders and agronomists will need to better match genotypes to environments and seasons.
“The aim is to understand the adaptation of current Australian cultivars in the context of the global diversity (that exists) in these characteristics,” Associate Professor Weller says.
“Appropriate phenology synchronises crop developmental stages to growing conditions. This can improve grain productivity and minimise the exposure to climate stresses. It is one of the most important aspects for adapting any annual crop to a particular production environment.”
Diversity panels
In 2019, ‘diversity panels’ representing global germplasm were assembled and screened in Hobart in a specialised glasshouse. Here, plants can be tested for their response to changes in daylength using an automated system that moves plants in and out of natural light.
Associate Professor Weller explains: “One of the most important factors in specifying major phenology differences is the plant’s response to changes in daylength.
“We used observations of this response to define a ‘panel’ of about 300 cultivars that best capture global variation in phenology.”
The genomes in this population were scanned for chromosomal regions that affect phenology using genome-wide association studies (GWAS).
In addition to this, the most contrasting lines were crossed – those that flower and mature earliest under short daylengths crossed with the late-flowering lines that require the longest daylength. Their progenies were then analysed. Together, these approaches allow the differences in phenology and related aspects of plant performance to be correlated with variation in the DNA sequence at specific genes.
Performance evaluation
Reference lines that lock in differing sets of these variants are also being generated in the form of near-isogenic lines (NILs). This will enable more extensive evaluations of performance in different locations to identify the most adaptive alleles for specific target production regions.
This will be used to create genomic breeding models and predictive tools. These models and tools will accelerate the development of better-adapted chickpea and lentil cultivars that maximise yield potential in existing and potential expansion areas. By 2023, significant associations (in the form of quantitative trait loci or QTLs) had been detected for a range of phenology traits across different growing environments. In all, changes in about half a dozen major genes were found to account for a shift from very early to very late growth patterns.
“Populations are now being grown to further refine the QTLs to the point of locating candidate genes that mediate this trait diversity,” Associate Professor Weller says.
This is the first time that the main genetic determinants of lentil phenology have been brought into such sharp focus. These are the genetic networks that most influence the timing of flowering, pod set and maturity.
The project has a national reach, with trial sites in Kapunda in South Australia, Gatton in Queensland and Merredin in Western Australia. Phenotyping includes the following traits:
- seed number;
- seed size;
- biomass;
- harvest index;
- flowering;
- pod emergence; and
- time from flowering to pod emergence.
Yield has been found to be strongly correlated to all of these traits except for seed size and the ‘time from flowering to pod emergence’, which showed a negative correlation. “Ultimately, the goal is to map the available diversity in phenology traits and build a genetic database that breeders can use to optimise the yield potential of lentil cultivars,” Associate Professor Weller says.
There are also opportunities to use the data to derive computer models of the gene-by-environment-by-management interactions with regards to phenology and yield. This would pave the way to predictive algorithms that further help breeders optimise lentil crop performance.
For this lentil project, the University of Tasmania team has been collaborating with researchers at the Crop Development Centre at the University of Saskatchewan in Canada. Besides chickpeas and lentils, work is also underway on field peas, common beans and soybeans in other collaborations that provide access to valuable new genomic resources and field data from across the world’s major pulse growing regions.
More information: James Weller, jim.weller@utas.edu.au
See also: GroundCover™ story – Grains research scholar: Raul Gimenez.
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