In vitro evolution of more thermostable dextranases for the Australian sugar industry. Dextrans are polysaccharides that adversely affect the productivity of sugarcane mills. The Australian sugar industry currently imports dextranases to deal with this problem but they are not heat stable so the mills have run at lower temperatures than optimal. We have isolated dextranases from thermophilic microorganisms and aim to improve their performance by generating superior heat-stable dextranases using ....In vitro evolution of more thermostable dextranases for the Australian sugar industry. Dextrans are polysaccharides that adversely affect the productivity of sugarcane mills. The Australian sugar industry currently imports dextranases to deal with this problem but they are not heat stable so the mills have run at lower temperatures than optimal. We have isolated dextranases from thermophilic microorganisms and aim to improve their performance by generating superior heat-stable dextranases using in vitro evolution, creating new activity levels by random mutation and recombination. The research will be significant in providing novel enzymes for domestic use, allowing import substitution and an outcome will be the development of a product with export potential.
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Understanding an exotic disease: Initiation of sex and infection by the sugarcane smut Ustilago scitaminea. Australian sugar exports generate almost $2 billion in annual sales, making the sugar industry a critical facet of the Australian economy. In 2006, Australia's primary sugar producing region came under threat when an outbreak of sugarcane smut caused by the fungus Ustilago scitaminea first appeared in Queensland. Management of this potentially devastating disease has focused on breeding pr ....Understanding an exotic disease: Initiation of sex and infection by the sugarcane smut Ustilago scitaminea. Australian sugar exports generate almost $2 billion in annual sales, making the sugar industry a critical facet of the Australian economy. In 2006, Australia's primary sugar producing region came under threat when an outbreak of sugarcane smut caused by the fungus Ustilago scitaminea first appeared in Queensland. Management of this potentially devastating disease has focused on breeding programmes aimed at developing resistant sugarcane cultivars, a complex process hampered by a lack of information about the mechanisms of smut resistance. Our research will provide key insight into the mechanisms by which U. scitaminea infects sugarcane, directing future breeding efforts and protecting this valuable industry against further outbreaks.Read moreRead less
Enhanced biocontrol options for the Australian sugar industry: a proteomic approach. Sugarcane is the second largest field crop grown in Australia and raw sugar is the third largest export product. Canegrubs are the major insect pest affecting production of sugarcane in Australia, currently costing the industry more than $12 million annually in insecticides and lost production. Biological control of insect pests provides an environmentally sound option of reducing these losses. Here we propos ....Enhanced biocontrol options for the Australian sugar industry: a proteomic approach. Sugarcane is the second largest field crop grown in Australia and raw sugar is the third largest export product. Canegrubs are the major insect pest affecting production of sugarcane in Australia, currently costing the industry more than $12 million annually in insecticides and lost production. Biological control of insect pests provides an environmentally sound option of reducing these losses. Here we propose to use proteomics to identify the key pathogenicity determinants in the biological control fungus Metarhizium during infection of canegrubs. The genes and proteins identified in this project will contribute to developing enhanced biocontrol options for Australian sugar industry.Read moreRead less
A New Window into Transgene Silencing in Plants: mechanisms of copy-number independent, 5' sequence dependent, post-transcriptional silencing in a complex polyploid. Silencing of introduced genes is a major problem limiting plant molecular improvement. Sugarcane, a complex polyploid, shows the most efficient transgene silencing ever observed in plants. Silencing operates on the RNA, depends on the upstream sequence of the gene, and is independent of copy number. Other plant species develop endop ....A New Window into Transgene Silencing in Plants: mechanisms of copy-number independent, 5' sequence dependent, post-transcriptional silencing in a complex polyploid. Silencing of introduced genes is a major problem limiting plant molecular improvement. Sugarcane, a complex polyploid, shows the most efficient transgene silencing ever observed in plants. Silencing operates on the RNA, depends on the upstream sequence of the gene, and is independent of copy number. Other plant species develop endopolyploidy with age, and show unpredictable or patchy silencing. We speculate that differential silencing is a natural control mechanism in the exploitation of polyploidy in plants. The sugarcane system provides an exceptional opportunity to identify the sequences that trigger and protect from silencing, and to develop approaches to avoid the problem.Read moreRead less
Genetic variation in the Cotesia flavipes complex of parasitic wasps: towards the effective biological control of stem-borer pests. This project will determine the genetic variation among world populations of the parasitic wasp Cotesia flavipes, as a prelude to the preemptive biological control of stemborer pests of sugarcane in Australia. These pests currently do not occur in Australia, but are found in crops across New Guinea and Indonesia, so that their incursion into Australia is highly lik ....Genetic variation in the Cotesia flavipes complex of parasitic wasps: towards the effective biological control of stem-borer pests. This project will determine the genetic variation among world populations of the parasitic wasp Cotesia flavipes, as a prelude to the preemptive biological control of stemborer pests of sugarcane in Australia. These pests currently do not occur in Australia, but are found in crops across New Guinea and Indonesia, so that their incursion into Australia is highly likely in the future. The results of this project will clarify the taxonomic status of C. flavipes-like species in Australia and provide the means, using molecular markers, to select host strains of this wasp suitable for the control of specific stemborer speciesRead moreRead less
Phylogeography and host specificity of stemborer parasitoids: essential components for the pre-emptive biocontrol of sugarcane pests in Australia. Stemboring insects cause huge economic losses to the sugar industry world-wide but fortunately these pests are largely absent from Australia, in part because quarantine measures have prevented their introduction. However, given their proximity, incursion of foreign stemborers from Asia pose a serious threat to Australian sugarcane. To prepare effectiv ....Phylogeography and host specificity of stemborer parasitoids: essential components for the pre-emptive biocontrol of sugarcane pests in Australia. Stemboring insects cause huge economic losses to the sugar industry world-wide but fortunately these pests are largely absent from Australia, in part because quarantine measures have prevented their introduction. However, given their proximity, incursion of foreign stemborers from Asia pose a serious threat to Australian sugarcane. To prepare effective pest management plans that can be adopted promptly in a worst-case scenario, this study will 1) develop molecular diagnostic tools to select wasp biocontrol agents that are suitable for the control of specific foreign stemborer pests, and 2) evaluate whether any Australian native wasps have the ability to kill foreign stemborers. Read moreRead less