- Standard plant breeding methods as currently used by Peasley Horticultural Services will be used for carrying out bi-parental crosses and self-fertilisations for the crossing program. Management of vines in Arboreta and trial sites under the direction of this project will be carried out using sub-contractors who will use current best practice industry methods to carry out pruning, disease and pest control measures and record information.
- Field trial sites not under the direction of this project will be managed by individual growers. We will suggest best-practice methods for recording trial information and including selected passionfruit varieties for standardising trial measurements. Information will be recorded in a central database operated by Southern Cross Plant Science (SCPS).
- Analysis of trial information will be carried out according to standard methods of trial assessments using statistical analysis where appropriate. Information on seed collected from controlled crosses will be recorded in a database at SCPS.
- Trial assessments will be carried out by growers in consultation with SCPS and with involvement of peak body vine and breeding committee members. For some crosses, more detailed information will be collected on trait inheritance patterns and measurements of characteristics of particular importance to industry – such as fruit quality.
- A subset of vines from some of these crosses will be genotyped using DNA markers to assist with determining the genomic location responsible for variation in traits of interest – which may include both quantitative and qualitative traits. Initial DNA marker generation is likely to be contracted to genotyping services after DNA extraction and verification of germplasm with markers at SCPS. SCPS may develop in-house genotyping for DNA markers showing promising association to traits of interest.
- Vine propagation and grafting will be carried out by nurseries specialised in this area or at SCPS after transfer of technical skills.
Detailed Breeding Plan
Task 1 – Gather trial information, co-ordinating grower trials and establish an Australian passionfruit varietal and trial database
Task 2 – In consultation with growers (1) determine best practice methods for trait measurements and (2) determine framework for trait based selection in the national breeding program
Task 3 – Establishing large single family crosses for superior variety selection and genetic analysis
Task 4 – Generate a reference genetic linkage map for Passiflora edulis using genome-wide DNA markers
Task 5 – Trait resolution and analysis
Task 6 – Initiate development of new inbred lines and create F1 varieties
Task 7 – Establish a replicated industry seedbank
Task 8 – Maintain and develop the industry arboretum