Show simple item record

dc.contributor.authorThornton, P. K.
dc.date.accessioned2010-05-07T00:54:10Z
dc.date.available2010-05-07T00:54:10Z
dc.date.issued1983
dc.identifier.urihttps://hdl.handle.net/10182/1815
dc.description.abstractConsiderable scope exists for the reduction of the primary and secondary costs associated with crop protection, by the formulation of judicious fungicide application regimes. The design, building and operation of a farm-level computer-based information system is described, the purpose of which is to help the farmer make rational spraying decisions. The system makes use of a simulation model built in 1978 which is capable of accurate prediction of the yield loss induced by epidemics of Puccinia hordei Otth on Hordeum vulgare L. cv. Zephyr. Extensions were made to this model to enable crop growth and disease to be projected into the future. Increased disease intensity occurs in response primarily to certain meteorological conditions; a model was built to carry out the probabilistic simulation of key weather variables. The Bayesian revision of yield reduction probability distributions provides the conceptual basis for the information system. The two strategies open to a decision maker as the season proceeds, those of spraying immediately and delaying application, were assessed using various decision criteria. Validation work was performed. Risk attitudes for a small sample of cereal growers were investigated; the importance of risk in the spraying decision is shown to be marginal. A low-cost method of implementation is illustrated; decision tables are derived on the basis of extensive simular experimentation and representative attitudes to risk. It is concluded that such an information system has the potential for the provision of timely recommendations. Areas for further research are identified; an. information system incorporating the major diseases of cereals in Canterbury is conceptualised, built around a general disease/crop skeleton model.en
dc.language.isoenen
dc.publisherLincoln College, University of Canterburyen
dc.rights.urihttps://researcharchive.lincoln.ac.nz/page/rights
dc.subjectleaf rusten
dc.subjectbarleyen
dc.subjectHordeum vulgare L.en
dc.subjectinformation systemsen
dc.subjectdecisionen
dc.subjectfungicidesen
dc.subjectBayesianen
dc.subjectcomputer simulationen
dc.subjectmodellingen
dc.subjectPuccinia hordei Otthen
dc.subjectdisease controlen
dc.titleInformation system design for the rationalisation of fungicide use : the control of Puccinia hordei Otthen
dc.typeThesisen
thesis.degree.grantorUniversity of Canterburyen
thesis.degree.levelDoctoralen
thesis.degree.nameDoctor of Philosophyen
dc.subject.marsdenFields of Research::280000 Information, Computing and Communication Sciences::280200 Artificial Intelligence and Signal and Image Processing::280210 Simulation and modellingen
dc.subject.marsdenFields of Research::300000 Agricultural, Veterinary and Environmental Sciences::300200 Crop and Pasture Production::300204 Plant protection (pests, diseases and weeds)en
dc.subject.marsdenFields of Research::340000 Economics::340200 Applied Economics::340201 Agricultural economicsen
dc.subject.marsdenFields of Research::230000 Mathematical Sciences::230200 Statistics::230202 Stochastic analysis and modellingen
lu.thesis.supervisorDent, Barry
lu.thesis.supervisorBeck, Tony
lu.contributor.unitDepartment of Applied Computingen


Files in this item

Default Thumbnail
Default Thumbnail

This item appears in the following Collection(s)

Show simple item record