Macadamia regional variety trials series 4 (MC17006)

Two Trial sites from RVT3 have now been harvested. Booyan or B2 RVT3 site was harvested for the second time on May 9 this season, while the Decortes RVT3 site was harvested on May 10 for the first time. Decortes had previously been harvested by Stahmann Webster prior to DAF getting permission to enter the site. As of the 19th of May, the Booyan site had dropped a total 948kg DNIS@1.5% MC from two harvests while Decortes had dropped 504 kg DNIS@1.5%MC.

On May 3rd at the Decortes private RVT site, six genotypes (HAES 741, MCT1, 1532, 215, 1208 and 54) had 30 kg of WNIH sampled, and a further 10kg WNIH sampled from each of 210 and MIV1-G. Lindsay Bryen took these bags of nuts to NSW for dehusking and drying before being delivered to Marquis macadamia processor for kernel analysis and roasting.

In March, trees of RVT4 selections were cinctured for June grafting at Wide Bay Seedlings near Tiaro. Through May grafting wood has been collected and delivered to the nursery. These selections are to make up the numbers for two trials planned for planting later in 2023.

Notes were taken on nut set and tree-form at the Farnsfield RVT4 site in March. In early May, nut and branch samples were collected from 17 trees for phenotyping to verify identity. No nuts were harvested from the NSW Wollongbar RVT4 site as the flowers were removed to encourage growth on this dryland site.

Trial planting resumed in 2022 with 20 spaces filled at the Wollongbar RVT, and a further 120 trees planted in the Southbank site near Yamba in March. The Yamba site went underwater in the NSW floods for a brief couple of days with no losses recorded. Similarly, the grower site at Pimlico, south of Ballina, also went underwater in the February floods and again in April which has now delayed planting until the middle of 2022. In April, 264 trees were planted in a grower site trial at a newly developed site at Magnolia, south of Maryborough. Rain in April and May has delayed the planting of another farm at the Ingleby site at North Isis until June.

Propagation of the remaining selections for the RVT4 trial sites will be with a new nursery in the Maryborough region. These selections have been difficult to propagate as there is only a single tree source for the planting material.

Wild weather and heavy rain have impacted the RVT4 harvest at Alstonville. In February the heavy rain had caused significant premature nut-drop at the Alstonville RVT3 site and considerable wash has moved nuts downslope to the ends of the rows. With this loss of crop and follow up rain events it was concluded that no meaningful data could be collected in 2022. Harvesting at the Booyan site in Bundaberg is on track while that Decortes block has again faced contract and farm visit issues so won’t be harvested in 2022.

Tree measurements were recorded at the Farnsfield trial site in Bundaberg. Trees at the site are growing well and surrounded by similar age orchard trees and varieties as the standards in the Regional Variety Trials (RVT).

Wollongbar comprehensive trial planting has commenced and is partially complete, with a total of 144 trees or 80 per cent of trees planted. Plans for completion are in place and are waiting additional trees to become available.

A supplementary grower trial was planted in October 2021 on a young farm in the Maclean region of NSW. There will be approximately 705 trees in total when planting is completed.

RVT-3 were harvested at Booyan and Alstonville in 2021.  NSW DPI staff completed two harvest rounds and a final strip pick at the Alstonville site, as COVID-related travel restrictions limited access by DAF project staff.

Since the last update, the first of three comprehensive trials was planted in September 2020 at Macadamias Australia’s Farnsfield site, southwest of Bundaberg. Of the intended 162 trees, 93 were planted in a randomised block design on a newly developed orchard site. Remaining tree spaces are to be planted in January/February 2021 when trees become available from the nursery.

At Mac Q nursery in Bundaberg, 1,969 H2 rootstocks were successfully grafted between June and October 2020 for grower supplementary trials. These will be dispatched in January 2021, with half destined for Rockhampton, Bundaberg and Maryborough grower sites, and the remaining trees going to Gympie and Northern Rivers, NSW. A final round of cincturing and propagation will be completed in early 2021.

The Decortes grower RVT harvest was delayed due to COVID-19 travel restrictions. It was harvested four times between May and July 2020, with the final visit combining a ground pick-up and tree strip. Yield data from 2019 and 2020 have now been collated and are being statistically analysed.

Decisions about selections to progress to commercialisation will be made by the Macadamia Industry Variety Improvement Committee in February 2021.

ACT NOW

Read more about 2020 Regional variety trials – testing and performance of new varieties since 1983 in the Australia Macadamia Society Bulletin, Summer 2020 edition, pp41-43.

Grower supplementary trial sites have been arranged for Rockhampton, Maryborough, Bundaberg, and two sites in the Northern Rivers of NSW. Plantings are on track for 2020 and 2021.

In Bundaberg, a comprehensive test site has been identified and is in the process of being established on previous sugar cane land.  Most new plantings in NSW and QLD are on previous sugar cane land, so the site will provide information that is relevant to current industry expansion.  Grafted nursery trees have been collected in readiness for comprehensive site plantings in the very near future.

A second comprehensive site is to be planted in an abnormal vertical growth affected site later in the year. Forty dwarf rootstocks are to be incorporated into this site as guard rows, to test compatibility, tree performance, and susceptibility to abnormal vertical growth.

This project is tasked with testing 23 new superior clones from seedling populations produced by the National Macadamia Breeding Project.

Locations for two comprehensive testing sites have been confirmed at Bundaberg and six supplementary grower blocks from the Northern Rivers region of NSW to Rockhampton in central Queensland.

At the comprehensive sites, a full range of data will be collected, with the supplementary trials to be a complementary data collection resource and useful tool for assessing localised performance and providing budwood supply for commercialised cultivars. 

Forty dwarf rootstocks will be planted at a Bundaberg site to test compatibility, tree performance and susceptibility to abnormal vertical growth.

In recent months, the project completed harvest of the 2019 Regional Variety Trials, with samples sent for analysis and nursery propagation started using two groups of cultivars. A further round of cincturing to be completed in March for May grafting.