National persimmon varietal evaluation program 2018-2023 (PR17000)

From 2018 to 2023, this investment worked to deliver superior and locally-adapted rootstocks for the Australian persimmon industry - suited to mainstay and new commercial varieties – and also continued to import and evaluate new persimmon varieties. 

The national persimmon varietal and rootstock evaluation program of Australia is a multi-stage process involving negotiations with overseas collaborators, importing varieties and rootstocks, post-quarantine entry requirements (PEQ), the release of trees from quarantine, establishing source trees, tree propagation post-PEQ, and establishing field trials followed by the evaluation and recommendation processes.  

The project was focused on (1) importing early maturing varieties and rootstocks from overseas, (2) the genetic verification of the ‘Rojo Brillante’ variety, (3) establishing trials for the existing varieties at NSW DPI Dareton Research Station (Dareton), and (4) developing a clonal propagation method to produce rootstock seedlings for the tree uniformity trials.  

During the project, strong collaboration was established with scientists and persimmon breeders from Spain, Japan, South Korea and China. The momentum of collaboration was maintained despite the hurdles of COVID-19 and the fact that a personal visit to these countries was not possible for the last three years.  

The Australian persimmon industry is dependent on the early maturing varieties from overseas. Therefore, significant efforts were made during this project to import the ‘Taishu’ variety from the University of Miyazaki, Japan. Since the variety has been in Australia, a budwood mother block has been established and buds will be available to growers in the next few years. The early maturing variety from South Korea will arrive in Australia in late 2023. True-to-type genetic verification of the Spanish ‘Rojo Brillante’ variety was required to confirm its originality. The genetic work was carried out in collaboration with the Spanish breeders. ‘Rojo Brillante’ DNA was extracted and compared to the original genetic markers in Spain. Phenotypic verification was also carried out to confirm the external appearance, shape, and internal quality characteristics by the Spanish scientist, Dr Maria Badenes. Subsequently, the budwood blocks were established at Dareton, and the budwood will be available to growers from September 2023.  

The Diospyros lotus rootstock was also imported from Spain. Rootstock seedlings were raised and grafted with ‘Jiro’, ‘Fuyu’ and ‘Rojo Brillante’ for evaluation purposes. Genetic work was carried out with a Spanish collaborator to identify the male and female trees, and the results were shared with Australia. After the verification, male and female trees were planted to establish the seed source for Diospyros lotus at Dareton. A replicated site was also established at a grower’s property in NSW as a backup. Australian growers now have access to the budwood from the new rootstocks at Dareton, which could help them establish their own seed source.