Tomato Yields and Leaf Miner Infestations and a Sequential Sampling Plan for Determining Need for Control Treatments1

Abstract

Tomato yields were reduced 4 of 9 years (1947-59) by leaf miner, Liriomyza sp., infestations in south Florida. Correlation coefficients were used to associate tomato yields and leaf mines. Linear regression equations show the expected yield reductions from leaf miner populations. With this information and a sequential sampling plan, an indication is obtained to determine a need for chemical control. Decision lines to spray or not to spray were proposed when 40% and 10% of the leaves averaged 1 or more mines per leaflet. A simple and reliable sampling plan is presented for determining these populations.