functions is knowledge intensive and often location specific. An important challenge for AKST will be to better elucidate underlying pest suppression mechanisms in diverse systems, such as through understanding how pest community genet­ics influence functional diversity (Clements et al., 2004). An equally important task will be to preserve local and tradi­tional knowledge in diverse agroecosystems
.
6.1.2.2 Tools for detection, prediction, and tracking AKST can contribute to development through the enhance­ment of capacity to predict and track the emergence of new pest threats. Some recent advances are discussed below.

Advances in remote sensing. Applications include linking remote sensing, pest predictive models, and GIS (Strand, 2000; Carruthers, 2003), and coupling wind dispersal and crop models to track wind-dispersed spores and insects (Ku-parinen, 2006; Pan et al., 2006). Recent advances in remote sensing have increased the utility of this technology for de­tecting crop damage from abiotic and biotic causal factors, thus remote sensing has good prospect for future integration with GIS and pest models. The spread of these technologies to low-income countries will likely to continue to be imped­ed by high equipment costs and lack of training. The further development and dissemination of low-cost thermocyclers for PCR (polymerase chain reaction) techniques could help to address this need. In general, a lack of training and poor facilities throughout most of the developing countries hin­ders the ability to keep up with, let alone address, new pest threats.

Advances in molecular-based tools. Emerging tools such as diagnostic arrays will help to better identify the emergence of new pest problems, and to differentiate pathovars, bio-vars, and races and monitor their movement in the land­scape (Garrett et al., 2006). Using molecular methods for pathogen identification has excellent potential in high-in­come countries.

Advances in modeling pest dynamics. Recent progress in de­veloping new mathematical approaches for modeling uncer­tainties and nonlinear thresholds, and for integrating pest and climate models, are providing insights into potential pest-host dynamics under climate change (Bourgeois et al., 2004; Garrett et al., 2006). Increased computational power is likely to facilitate advances in modeling techniques for understanding the effects of climate change on pests. How­ever, the predictive capacity of these models could continue, as it currently is, to be hampered by scale limitations of data generated by growth chamber and field plot experi­ments, inadequate information concerning pest geographi­cal range, and poor understanding of how temperature and CO2 interactions affect pest-host dynamics (Hoover and Newman, 2004; Scherm, 2004; Chakaborty, 2005; Zvereva and Kozlov, 2006). Greater focus on addressing these limi­tations is needed. Improved modeling capacity is needed for understanding how extreme climate events trigger pest and disease outbreaks (Fuhrer, 2003). Modeling pests of tropical agriculture will likely have the greatest impact on helping AKST to address food security challenges, as these regions will be most negatively affected by climate change. This will

require a substantial investment in training, education, and capacity development.

Prevention of invasive alien species. The invasive alien spe­cies issue is complex in that an introduced organism can be a noxious invasive in one context yet a desirable addi­tion (at least initially) in another (McNeely, 2006). Inter­national assistance programs (development projects, food aid for disaster relief, and military assistance) are an impor­tant means through which IAS are introduced into terres­trial and freshwater systems, as in the case of fast growing agroforestry trees, aquaculture species, and weed seed-con­taminated grain shipments (Murphy and Cheesman, 2006). Addressing this problem will require much more detailed information on the extent of the problem, as well as greater understanding of vectors and pathways. Raising aware­ness in the international aid community, such as through toolkits developed by the Global Invasive Species Program (GISP, 2004) are an important first step, as are prerelease risk assessments for species planned for deliberate release (Murphy and Cheesman, 2006).
     More rigorous risk assessment methods are needed to determine the pest potential of accidentally introduced or­ganisms and those intentionally introduced, such as for food and timber production, biological control, or soil stabili­zation. Elements needed to build risk assessment capacity include broad access to scientific literature about introduced species, access to advanced modeling software and process­ing time, improved expertise for determining risks related to invasive characteristics, and development of public aware­ness campaigns to prevent introduction (GISP, 2004).

     Early detection of invasive alien species. The capacity to sur­vey for introduction of nonnative species of concern could be enhanced. Where resources for conducting surveys are limited, surveys can prioritize towards species known to be invasive and that have a high likelihood of introduction at high risk entry points, or areas with high value biodiversity (GISP, 2004). Develop contingency planning for economi­cally important IAS.

Management of invasive alien species. Current mechanical, chemical and biological control methods are likely to con­tinue to be important in the future. In the case of biologi­cal control, the use of plant pathogens as natural enemies is emerging as an alternative or complement to classical biological control using arthropods, and it is being piloted in tropical Asia for controlling the highly damaging weed, Mikania micrantha (Ellison et al., 2005). Additionally, new and emerging genomic tools could aid IAS management, particularly for preventing the conversion of crops into weeds (Al-Ahmad et al., 2006).
     Basic quantitative data on the impacts and scale of the IAS problem is still lacking in many developing countries (El­lison et al., 2005). Gaining greater knowledge of the extent of the problem will require better cross-sectoral linkages, such as between institutions that serve agriculture, natural resource management, and environmental protection.
     Risk assessment for entry, establishment, and spread is a newly developing area for IAS (GISP, 2004). For example, Australia recently instituted a weed risk assessment system