New custard apple varieties and enhanced industry productivity (CU16002)

What was it all about?

Running from 2018 to 2021, this investment developed new high-yielding green and red skin custard apple selections, evaluated the performance of clonal and seedling rootstock selections and increased grower awareness and knowledge of a range of production issues through a series of industry development field days and workshops.

This project built on the previous project phase Accelerating development of the Australian custard apple industry, new variety development and commercialisation phase 2 (CU13001).

Over 2000 hybrid progeny were established during the project term using red and pink skin parents. Approximately 1800 hybrid seedlings were evaluated for tree and fruit characteristics, resulting in over 40 new selections being identified for further evaluation.

A series of trials evaluating new elite selections from the breeding program was established in the previous project phase. Evaluation of these selections in major production regions has resulted in three green skin selections being recommended for commercialisation. Two promising red skin selections have also performed well in trials, however further evaluation will be required before they are progressed to commercialisation. Rootstock trials have evaluated a range of seedling and clonal rootstocks and recommendations have been developed on their suitability for different growing regions. 

A small clonal propagation program with a collaborating nursery in North Queensland has successfully produced rootstock of cherimoya and DAF selection 450. Strike rates of over 75 per cent in selection 450 means commercial quantities of this rootstock will become available for industry as the program progresses. Although high strike rates were also reported in cherimoya rootstocks the growth habit of the tree was not ideal for grafting.  

The project team has shared progress with industry through several Custard Apple Australia events held in Alstonville, Bundaberg and the Glasshouse Maintains as part of the levy-funded project Custard apple communication and extension program (CU16001). Several articles were also published in the industry newsletter, The Custard Apple.