Sequential sampling plans and economic injury levels for Empoasca kraemeri on common bean crops at different technological levels

Abstract

All three economic injury levels determined and the sequential sampling plans developed in this study are suitable for incorporation into integrated management programs for common bean pests because they can be used by farmers operating at various technological levels to make adequate and rapid decisions. © 2017 Society of Chemical Industry.

Economic injury levels and sequential sampling plans for control decision‐making systems of Bemisia tabaci biotype B adults in watermelon crops

“…The relationship between plant productivity and pest density can be represented by three types of curves . In the first type, curves have a downward concavity and belong to pest‐tolerant plants.…”

“…The insecticides selected were those used most by farmers, and with different modes of action, to manage the insecticide resistance in the pests. From these data, the cost of controlling whiteflies in watermelon crops was calculated …”

“…A regression analysis of the crop production value as a function of the density of whitefly adults at each plant stage (vegetative and reproductive) and watermelon price (low, average, and high) was also conducted. The regression model was selected based on the model significance ( P < 0.05), highest coefficient of regression ( R 2 ), simplicity of the equation, and biological meaning …”

“…Crop production values were determined when the pest attack was equal to the EIL using Eqn 3: where V EDL is the crop production value when the pest attack was equal to the EIL (US$ ha −1 ), V 0 is the production value when the crop is not attacked by the pest (US$ ha −1 ), and Pl is the injury level in terms of percent loss (%).…”

“…However in sequential sampling plans, the number of samples is variable, and plans are validated when the decisions reached are similar to those of the conventional plan, but with reduced sampling time and cost. Sequential sampling plans have two decision‐making thresholds, one lower (non‐control decision‐making) and one upper (control decision‐making) …”