New intensive mango management systems including high-density and trellis designs are currently being trialled by the Department of Agriculture and Fisheries in Queensland (DAF) in both the ‘Small Tree High Productivity Initiative’ (STHPI) and the ‘Cyclone Resilience’ projects.
The STHPI is an initiative of DAF, University of Queensland-QAAFI and the NSW Department of Primary Industries with key funding from Hort Innovation. The Cyclone Resilience project is funded by DAF and AgriFutures Australia. Both projects have shown great promise in significantly increasing the size and reliability of fruit yields. Added benefits include tree canopies suitable to potential mechanisation or robotics, greater production efficiency and greater cyclone resilience.
Since the beginning of the STHPI in 2013 researchers have gained a better understanding of factors such as vegetative vigour, planting density, tree architecture, canopy light relations and crop load that influence productivity of avocado, macadamia and mango when grown in high-density orchard systems. The first phase of this project will be complete in December this year.
The Cyclone Resilience project, running since 2013, came out of on-farm experience in cyclone Larry, where exotic tropical fruit trees grown on trellis withstood much of the devastating cyclonic winds. Trellising was a valuable insurance policy to saving crops from imminent destruction during cyclone events. The Cyclone Resilience project has been investigating the practicality, productivity and costs of production of trellising systems for tree crops such as lychee, rambutan, durian, mangosteen, jackfruit, macadamia, avocado and mango.
The main mango component of the STHPI is a field planting systems trial on DAF’s Walkamin Research Station that has three mango varieties ‘Keitt’, ‘Calypso’ and ‘NMBP 1243’ growing at high (1250 trees per hectare), medium (416 trees per hectare) and low (208 trees per hectare) planting densities. In the high-density plots, trees are trained as either hedges or espalier on trellis. In the medium density plots, trees are trained conventionally or as single leaders. In the low density plots trees are all trained conventionally.
The most recent production data from the 2017/2018 season saw a continued trend of outstanding results for the high-density planting system, four years after planting.
For all three cultivars, yields were significantly higher when grown at high-density compared to medium and low-densities, with the highest yield of 46.9 tonnes per hectare produced by espalier trained ‘Keitt’ grown on trellis. Low-density conventional trees produced the lowest yield across all varieties.
In the mango component of the Cyclone Resilience project, a trial site in Mareeba with trellised ‘Honey Gold’ mangos produced an encouraging yield of 43 tonnes per hectare at age 5 years.
Results and learnings from both these projects have encouraged further enthusiasm to evaluate intensive mango production systems as part of a new project funded by the Cooperative Research Centre for Developing Northern Australia (CRCNA). Two large mango growers; Manbulloo Ltd and BJM Enterprises, wish to grow their businesses through greater production of high-quality fruit, suitable for domestic and Asian export markets. These growers have now formed an industry-led venture with DAF in Queensland and the Australian Mango Industry Association (AMIA) to commercially trial new mango intensification techniques.
Using learnings from the STHPI and ‘Cyclone Resilience’ projects, high-density mango orchard technologies will be established as commercial-scale research trials in Queensland at Mareeba and Bowen and in the Northern Territory at Katherine. The trials will use ‘Kensington Pride’, ‘R2E2’ and two new ‘NMBP’ varieties to facilitate the transition to next-generation, high-productivity orchard systems. This research joint venture will concurrently investigate industry transition issues from conventional to next generation systems and answer key orchard management questions arising from the change process.
This project will create impact for national industry growth through more productive, resilient and reliable mango orchards, able to service and grow export markets.