System simulation in disease management, barley leaf rust as a case study

Abstract

The systems approach as a scientific philosophy takes a holistic view of life, its many supporting systems and their interlocking components. However, apart from just being a concept, the approach has been translated into a well-defined science, with its set of methods, Early in this session, the basic framework of systems theory in relation to agriculture was provided by Dent (1977), who also noted that part and parcel of the study of a system involved the construction of a model of some kind to represent the system. We were then warned of the pitfalls and problems associated with modelling (Blackie, 1971), and how the multidisciplinary approach inherent with the systems view depends very much on the ability of scientists to work together as a team, In the following talk I would like to illustrate how systems methodology can be used, (a) for studying the dynamic nature of plant disease epidemics, and (b) for integrating the information on disease epidemiology and crop loss into practical management schemes. As an example, a case study will be made with barley leaf rust caused by Puccinia hordei Otth (Teng et al;, 1977a; 1977b).