Bernard Dell

There have been widespread climate induced impacts in natural and plantation forests both within Australia and overseas, and modelling suggests a markedly different future climate. New thinking and approaches to forest management may be required. In Australia there are over 149 million ha of forests; in the approx. 8 million ha of managed natural and planted forests foresters have always dealt with climate-induced uncertainty. These past experiences may help to deal with future conditions although the limit to which this will be constrained by finance and public opinion is unknown. This paper will examine how forests respond to climate, past climate change impacts in forests, the management responses to those events, the role of climate change mitigation (reforestation, forest management, bioenergy) and then explore how this aids the development of future climate change adaptation strategies.

Short rotation energy crops have the potential to provide sustainable sources of biomass, but the efficient use of nutrients will be crucial to ensure that these systems are sustainable. In dryland environments 3- to 5-yr rotations of tree crops integrated with agriculture represent a major potential bioenergy feedstock and a means to restore landscape hydrologic balances, while maintaining food production. In soils with low natural fertility, the long-term viability of these systems is critically affected by site nutrient status and subsequent cycling of nutrients. A nutrient assimilation index (NAI) was developed to allow comparison of the nutrient assimilation between tree species and tree components, to optimise nutrient management, and to quantify different strategies to manage nutrients. Biomass, nutrient export, and nutrient use efficiency were assessed for three short rotation tree crop species (Eucalyptus globulus, E. occidentalis, Pinus radiata). Component NAI was generally in the order of leaf

Tall, dry sclerophyll forests characterise parts of south-western Australia with a mediterranean-climate. The jarrah forest is managed for multi-purpose use including conservation, water supply, mining, timber harvesting and recreation. This paper will briefly describe the historical setting of land-use and then examine recent climate events impacting on forest health. These include a decline in rainfall and groundwater levels, reduced stream flow, increased incidence of drought, increased forest dieback and mass collapse. Finally, measures to manage forest decline are considered.

Stem rot disease caused by Sclerotinia sclerotiorum has emerged as a serious problem on canola (Brassica napus L.) production in Western Australia (WA) over the past few years where crop losses can be up to 40% in the worst affected crops. Hundreds of isolates of S. sclerotiorum have been collected from different canola growing regions of WA. As the majority of WA isolates of S. sclerotiorum have not been analyzed for their genetic characterization, analysis of genetic variation of WA isolates will be undertaken using classical and molecular techniques such as pathogenicity test, mycelial compatibility groups (MCGs), ITS sequencing, and cluster analysis. The experiments which started in March 2013, aim to use classical and molecular tools to identify groups of WA isolates of S. sclerotiorum from which isolates will be selected for the main studies on the management of S. sclerotiorum in canola. Accurate information of genetic diversity through research on characterization of the pathogen will lead to better understanding of the pathogen and will also benefit the breeding programs particularly aiming at breeding for disease resistance and moreover, could lead to developing better techniques for managing the disease. The paper provides an outline of the experiments and preliminary results.

The genes/enzymes involved in supplying carbon to the developing head in wheat are not well characterized. The activities of cell wall invertases (IVR1s) are known to be important in supplying sugars to pollen during the early stages of head development. Recently multiple IVR1 isoforms were identified on the wheat genome (Webster et al 2012; Funct Plant Biol 39: 569 - 579; GRDC-GRS10028) and were found to be located on a number of chromosome arms. These findings in addition to the existence of IVR1 inhibitors, provides evidence to suggest a complex regulatory network exists, which controls the flow of sugars to maturing pollen. A reduction in supply of sugars to pollen in response to water stress during the early stages of maturation leads to sterility. A large water stress experiment was carried out to analyse the transcriptome using RNASeq and RNA from developing wheat heads. RNASeq performed on tissues extracted from developing heads, extending from immature floret formation through to anthesis, enabled temporal profiling of transcript expression in response to water stress and non-limited water conditions. The IWGSC wheat genome survey sequence data was used as the reference to assign chromosome arm locations of those transcripts showing expression in the RNASeq data. Mapping individual transcripts to an IWGSC survey sequence contig facilitated downstream functional and biological characterisation to identify key genes involved in the supply of carbon to developing wheat heads.

Teratosphaeria destructans was first described in 1996 from north Sumatra, Indonesia, where it caused a severe leaf and shoot blight on Eucalyptus grandis in nurseries and young plantations. Since then it has been reported in nurseries and plantations in Vietnam, Thailand and China, with its host range extending to include E. camaldulensis and E. urophylla. Teratosphaeria destructans has also been reported from native E. urophylla in East Timor and was considered a significant biosecurity threat to Australia’s native eucalypt forests and plantations. A study on the population diversity of K. destructans isolates throughout south‐east Asia in which 8 gene regions were sequenced (four nuclear genes, one mitochondrial gene and three microsatellite markers) detected very low nucleotide polymorphism. This genetic uniformity is indicative of an introduced population which has subsequently spread throughout Asia via human‐mediated movement of germplasm. Surveys of sentinel plantings in northern Australia (Queensland, Northern Territory and Western Australia) revealed a complex of Teratosphaeria spp. Among which K. destructans was detected. The same gene regions and markers were sequenced as for the Asian study and the diversity among the K. destructans isolates in Australia was found to be much greater than that in Asia. We believe that K. destructans in native to Australia where is resides asymptomatically within the native vegetation. The disease is only expressed when non‐endemic eucalypts are planted. As such the pathogen is a major encumbrance to the establishment of commercial eucalypt plantations in Northern Australia. The disease has not been observed in native ecosystems, but the effect of inoculum build up within plantations on adjacent native eucalypt remnants is not known.

In Western Australia there are a number of substantial declines and deaths across a number of forest and woodland tree species. These include Eucalyptus marginata, E. gomphocephela (tuart), E. wandoo (wandoo), E. rudis (swamp gum), Agonis flexuosa (peppermint) and Corymbia calophylla (marri). There are many theories put forward as to the reasons for these declines including: (i) global climate change; (ii) habitat loss and fragmentation; (iii) changes in land management, e.g. the absence of planned fire, damage from wildfires, and past timber harvesting and grazing; (iv) weeds, pests and diseases; (v) salinity; (vi) changes in hydrology; (vii) poorly developed links between research and management; and (viii) sub‐optimal management policies and strategies at Local and State Government levels. The Centre is made up of three core research organisations, 27 collaborating industry partners and seven collaborating international and national institutions. An overview of these declines, the possible causes, their implications to ecosystem function and health and the different research and adaptive management approaches that are in place to understand and mitigate these declines will be discussed.