Táticas de controle de dolichotetranychus floridanus banks, 1900 acari: tenuipalpidae na cultura do abacaxi ananas comosus L. merril

Abstract

The cultivation of pineapple (Ananas comosus L. Merril) is an economically significant activity in several Brazilian states, but it faces serious challenges due to pest attacks, particularly the false spider mite (Dolichotetranychus floridanus Banks, 1900), which causes substantial losses. However, detailed studies on the mites affecting this crop and effective control strategies are lacking. This study aims to develop control tactics for D. floridanus using chemical, biological, and molecular tools for accurate species identification to improve management strategies. For chemical control, a randomized block experimental design with five treatments and four replications was used. The products tested were Abamectin®, Orthene®, Lorsban®, Pirate®, and water (control). The application doses ranged from 50 mL/50 L to 75 mL/50 L. Laboratory evaluations were conducted at 2, 4, 8, and 16 days after treatment. Lorsban® and Pirate® were the most effective, with Lorsban® achieving 100% mite mortality by the second day. For biological control, colonies of predatory mites from the genus Cosmolaelaps wereestablished in plastic containers, fed with phytophagous nematodes, and maintained with daily water additions to ensure proper humidity. Predatory capacity was evaluated atintervals of 24, 48, 72, and 96 hours, and adult females of Cosmolaelaps sp. consumed an average of 35.5 D. floridanus mites, showing promise as a biological control option. For molecular characterization, pineapple seedlings were collected from five northeastern states (Alagoas, Bahia, Paraíba, Pernambuco, and Sergipe). The material was stored at - 20°C and subjected to DNA extraction. The genetic markers COI and ITS were used, with regions amplified via PCR, and the sequenced data were compared to the NCBI database. Phylogenetic analyses performed using MEGA v. 7 indicated genetic uniformity among D. floridanus populations from different regions, suggesting high population stability. The results indicate that combining chemical and biological control with molecular characterization can aid in managing D. floridanus, contributing to the development of more efficient and sustainable strategies for controlling this pest in pineapple cultivation. Key-words: Bromeliaceae, Tenuipalpidae, genetic uniformity, biological control