ABSTRACT
During 1987, a sequential sampling plan for pink bollworm, Pectinophora gossypiella (Saunders), eggs was field-tested in eight 40-acre fields in the Palo Verde Valley, CA. Final analysis of the sequential procedure, including the time necessary to collect and check all bolls, required an average sampling time of 16 minutes/field, ca. a 70% savings over the fixed sample size of 160 bolls/field. Using the sequential plan, the number of bolls examined on any given sample date ranged from 25 to 100/field, depending on egg density, and averaged 46.75/field. The sequential sampling plan error rate for making no-treat recommendations when a field actually required treatment (i.e., actual egg infestation ò6%) averaged only 6.4% throughout the season (n = 156 decision comparisons).
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