HLB, citrus genomics the focus of International Citrus Congress
The International Citrus Congress held in Brazil from September 18-23 focussed heavily on Huanlongbing (HLB) and citrus genomics and breeding.
Citrus Australia South Australia Region acting chair, Steve Burdette, who attended the conference, said about 45% of the scientific presentations and workshops conducted during the conference focussed on these two areas.
“This is a sure indication of where international research in citrus producing countries around the world is focussed at present,” Steve said.
“The increase in the Citrus Biosecurity levy in the Australian Citrus industry is considered to be a very important strategic decision due to the increased threat of HLB around the world.
“The Australian Citrus Industry must do everything possible to keep the disease out but must also be prepared and have an action plan in place in the event of an HLB incursion.”
HLB has become a major challenge in most of the larger citrus producing countries of the world with significant amount of money being invested in R&D, surveillance, eradication, training and control measures.
The conference was told the only short term solution at this stage appears to be Integrated Orchard Management Practices which significantly increases production costs.
The longer term solution appears to be breeding for resistance which will take many years before it is commercially viable.
Early detection of the disease is critical while protection and traceability of nursery citrus propagation material in insect proof structures is equally important should HLB be detected in Australia.
In Florida alone total acreage planted has decreased from 900,000 acres to 520,000 acres with production dropping from 160-180 million boxes to 100 million boxes over a six-year period.
This is having a major impact on the 6000 small and large growers and 76,000 employees involved in the Floridian Citrus Industry. The economic impact is estimated to be US$ 8.9 billion.
The presentations on citrus genetics and breeding revealed there has been an explosion of breeding programs around the world resulting in the release of new citrus cultivars and rootstocks.
“Significant advancement is being made in this field as new sequencing technology and marker development has been developed to breed varieties and rootstocks for specific traits,” Steve said.
“Despite these advances in research it is important to emphasise that many of the existing citrus cultivars have been derived from branch mutations and irradiation.
“All these new citrus cultivars and rootstocks still require thorough testing and evaluation to ensure they are commercially viable in different production regions of Australia.”