Objective 2

To reduce the impact associated with Ceratocystis canker and wilt disease in A. mangium plantations.

There are significant gaps in knowledge about this new disease which need to be filled for successful disease management and the successful deployment of any genetic resistance which may be found during this project. Activities planned include:

2.1 To identify the insects associated with C. acaciivora and to consider the significance of this mechanism by which the pathogen spreads.

2.2 Screening acacia deployment populations to develop disease resistant breeds

(Indonesia, Vietnam)

In Indonesia, acacia germplasm managed by the lead Indonesian partner (CFBTI) will be screened, using an agreed screening protocol, for Ceratocystis resistance. Making it operationally feasible to screen massive populations will be managed by industry partners. In Vietnam, existing hybrid acacia clones will be the initial populations screened for resistance. Screening of advanced generation selections from Acacia mangium and A. auriculiformis populations will take place in southern Vietnam where risk of the disease is highest.

2.3 Developing robust disease screening systems; large numbers of individuals must be screened and efficient systems are required to integrate into existing breeding programs. A range of experiments are planned to evaluate the following key variables of the screening system; host age, multiple vs single strains, stem vs. excised log vs. leaf inoculation as well as the time strains have been in culture.

2.4 Breeding and deployment strategy revision with technology transfer; the current breeding strategy for acacias focuses on increasing productivity and wood quality traits with attention given to risk mitigation opportunistically. Revision of the breeding strategies for the major acacia species will be undertaken with project partners in Vietnam and Indonesia to provide a systematic approach to developing disease resistance