Spatial Distribution and Sequential Sampling Plan for Soil Insect Pests in Potatoes
by
Joanne De Faveri
Queensland Horticulture Institute, Queensland Department of Primary Industries
Coauthors: Stewart Learmonth (Agriculture Western Australia), Stefano De Faveri (Queensland Department of Primary Industries)

Soil borne insect pests cause a problem for potato growers by effecting potato tuber quality and yield. Currently most growers chemically treat every crop. A National project has been established to develop an integrated pest management (IPM) program for these soil pests in potatoes. This IPM program aims to reduce pesticide use by setting up decision-making protocols to assess whether chemical intervention is necessary. An essential part of this IPM program is the development of a reliable and cost effective pre–plant sampling program.

To develop such a sampling plan it is important to understand the density and spatial distribution of the soil insects in the field. In this talk I will consider spatial analysis techniques, for example variograms (geostatistics) and SADIE (spatial analysis using distance indices), to quantify spatial pattern in the soil insect data.

I will also discuss the design of a sequential classification sampling plan for grower implementation.

Date received: September 6, 2002