Cultivation of Native Potatoes – Progress Report

Progress report on the grant:

[AFF contribution to RIRDC project no: UWA-16A: Development of new root vegetable crops from Western Australia’s diverse tuberous flora.]

Dr Geof Woodall, Professor Marcus Blacklow and Paula Deegan, Centre of Excellence in National Resource Management, University of Western Australia

Progress report 28/11/2005

This project aims to systematically assess the horticultural potential of southern Western Australia’s diverse tuberous flora and commence commercialisation of promising species as new vegetable crops.

Available knowledge has been reviewed and information used to select the target group of species, assist with propagation and set context of nutritional work. On the basis of the products, their utilisation and horticultural attributes, three species have been selected for further study: Platysace deflexa (Apiaceae), Ipomoea calobra (Convolvulaceae) and Haemodorum spicatum (Haemodoraceae). Dioscorea hastifolia was investigated and was deemed unsuitable for inclusion in this target group. Discussion with Greg Keighery revealed that this species should not be excluded until the Northampton provenance had been assessed. This assessment will be done late November 2005

Commercialisation strategies for Platysace deflexa and Haemodorum spicatum are being investigated with a preliminary assessment of market strategy opportunities, target markets, potential points of difference and product specifications conducted.

Propagation
Robust propagation procedures have been developed for Ipomoea calobra (scarified seed and asexual propagation) with propagation from seed having most commercial promise (not yet tested under field conditions).
Field propagation procedures for Haemodorum spicatum have been developed. Systems for the propagation of Platysace deflexa are developing, however all field trials failed due to a 1 in 50 year climate event (300mm of rainfall in one day in an area with mean annual rainfall of 550mm). A better understanding of tuber sprouting is emerging.

Production
Ipomoea calobra
is being cultivated at a reasonable scale under hothouse conditions in Albany, the aim being to produce enough product by May 2006 to enable a comprehensive product assessment.
A small field trial of direct sown Haemodorum spicatum seed was established at Bremer Bay. Adverse seasonal conditions have affected the trial but the net result has been very encouraging.
Platysace deflexa has been cultivated at two sites, one at Bremer Bay and the other at Gairdner. Although some plants still remain (5%) the effect of all treatments has been over shadowed by the very wet seasonal conditions of the 2005 growing season.
The first (ever) harvest and yield data have been obtained for field cultivated Platysace deflexa. The results were encouraging, with a yield of approximately 1 kg per plant with improved sweetness and protein content (compared with wild harvested material).
Tuber formation and yield data has been obtained for Ipomoea calobra grown in Albany in a hot-house pot trial. Production of a carrot sized product occurred within 4 months.
The possible accumulation of oxalate in Haemodorum spicatum bulbs was investigated. No evidence of toxic levels was found.
Growth of field and pot grown Haemodorum spicatum has commenced Nutritional analysis of products has commenced

Consumer appraisal
A preliminary consumer appraisal has been conducted for Haemodorum spicatum and Platysace deflexa at two separate events with 67 participants providing written feedback on their response to key product appraisal characteristics. Additional activities are planned for 2006 to further product testing and investigation of target markets and retailers. Ipomoea calobra product appraisal is scheduled for late autumn 2006 (subject to the product formation by the cultivated material).
There has been a willingness expressed by members of the Great Southern Marketing Association, food retailers and food industry professionals within the region to providing input into events planned for 2006 aimed at progressing product awareness and market development, such as a regionally based focus group, tastings and dinner workshop.

G Woodall Principal Investigator 28/11/2005