Genomics to speed the process
Issue
- Tree breeding is slow and it may take up to 25-30 years before the new genetics enters commercial production.
- If the length of this breeding and deployment cycle can be halved, the impact would be to double genetic gain available over time and increase the rate of improvement in key traits of economic importance.
Genomic selection
Genomic selection represents a step-change in animal and plant breeding. Together with the introduction of forward selection, it will allow the early selection of genotypes for deployment without the need for progeny testing. Multiple traits can be assessed simultaneously.
The technology would shorten the breeding and deployment cycle by some 15 years, and deliver twice the gain per unit time.
Outline of Science Programme
Partial genetic sequencing of radiata pine (not expensive) and the identification and selection of SNPs (like small “snippets” of DNA) to act as molecular markers for expressed genes. (Full sequence and mapping in associated research at Scion).
SNPS are then distributed in very small quantities on a SNP chip. This is technology that has been commercialised and will be purchased internationally. Initially, 50,000 SNPs will be placed on a chip, with each chip costing some $500 and requiring a minimum production of 1200.
The next stage involves “training” where genotypes with known phenotypic data for traits of interest have their DNA extracted and tested against the SNP chip. Matches between the two relate patterns on the SNP chip with presence of genes associated with traits. SNPs of no function are discarded. A chip can only be used once against one tree.
The target commercial chip will be smaller (3-5,000 SNPs) and cheaper. It will be used to screen parents of the production and elite populations and for the development of genetic breeding values (GeBVs). This information will be used for breeding and particularly deployment decisions. Testing and validation procedures will be included.
Regional clonal testing of selected genotypes will provide the early multiplication phase for delivery of planting stock by 2022.
Costs
The cost of the upcoming 5-year R&D programme, commencing F14, is estimated at $1 million a year (total $5 million). An application for funding will be made to MBIE to establish a research partnership.
This will require industry to supply 50% of the required funding, namely $500k a year for 5 years.
Potential Benefits
The Genomic Selection programme will deliver improved planting stock for commercial deployment in 2022.
Current genetic improvement will deliver some additional 15% gain over the period to 2050. The first impact of genomic selection will deliver an additional 15% gain by 2050.
Total gain achievable by 2050, expressed as gain in volume, will therefore be in the order of 30%.
This equates to an increase of 135m³/ha, and an increase in value of some $12,000/ha at the end of rotation calculated on a current production of 450m³/ha. Additional pulses of some 10% gain (ca. 40-50m³ volume equivalent) will follow at 8-10 year intervals.
