Designing a robust strategy to scout a key pest in cashew orchards

Abstract

The cashew (Anacardium occidentale) is a fruit tree grown in tropical regions producing the nut most consumed worldwide. The brown moth Anacampsis phytomiella (Lepidoptera: Gelechiidae) is the primary pest that attacks cashew nuts in the Neotropical region. Sampling plans are essential components of integrated pest management (IPM) programs. These sampling plans determine the procedure to scout pest populations and the number of samples to be evaluated per plot. Besides estimating pest densities accurately, sampling plans must be feasible (simple methodology), fast, and cost-effective to the farmers. However, sampling plans for A. phytomiella have not been determined so far. Hence, this study aimed to determine a robust conventional sampling plan to scout the brown moth in cashew orchards. For this purpose, the best methodology for assessing pest attack intensity, number of samples, scouting time, and sampling plan costs in cashew orchards were selected during two years. The sampling plan evaluates the percentage of green cashew nuts attacked by the pest in four branches per 22 plants orchard, yielding 88 samples per plot. This sampling procedure lasted 28, 38, and 45 min and cost US $1.06, US $1.42, and US $1.69 for orchards of 1, 5, and 10 ha, respectively. Therefore, this study designed an accurate and practicable strategy to scout A. phytomiella in cashew orchards.