Methodology for rearing of Amblydromalus limonicus (Acari: Phytoseiidae) in laboratory, and biological control of whiteflies and thrips (Thysanoptera) using the predator mite in different agricultural crops

Abstract

The crops of vegetables and ornamental plants are characterized by demanding high investment per unit of area, generally using large amount of labor. The whitefly, Bemisia tabaci (Genn.) (Hemiptera) causes direct damage in a large number of agricultural crops, besides acting as vector of several phytoviruses. Thrips (Thysanoptera) also cause injury in many crops of agricultural importance, and some species can transmit viruses. These species include Frankliniella occidentallis (Pergande) (Thysanoptera: Thripidae) which is an important pest of several crops in Brazil, including ornamental and horticultural plants. One of the problems associated with these pests is the rapid development of resistance to insecticides, hampering their control through the use of pesticides. Predators of the Phytoseiidae family are considered the main agents of biological control of phytophagous mites in agricultural crops, and may also control some insect pests. The species Amblydromalus limonicus (Garman & McGregor) (Acari: Phytoseiidae) has been shown to be efficient for whitefly control in greenhouse crops, and to reduce the population density of nymphs of thrips. One of the main factors associated with the difficulty of using this predator in biological pest control programs in Brazil is the lack of an adequate methodology of mass rearing for this predator under laboratory conditions. The availability of an efficient and low-cost technique for rearing of A. limonicus could benefit a large number of farmers who suffer from the damage caused by these insect pests and the associated viruses. The objective of the project is to evaluate the potential of the use of Amblydromalus limonicus for the biological control of whiteflies (Bemisia tabaci) and tripes (Frankiniella sp.) in different crops (chayote, eggplant, gerbera) and to improve the rearing method for the predatory mite in laboratory. The specific objectives are: 1) To evaluate different food sources and methodologies for mass rearing of the predatory mite A. limonicus in the laboratory; 2) To evaluate the influence of different food sources and rearing methods on the performance of the predatory mite for the biological control of whiteflies and thrips, under laboratory and field conditions; 3) To evaluate the production costs of the predator mite for the different rearing methods; 4) To evaluate the influence of different cultures (chayote, eggplant, gerbera) and spontaneous plants present in the field, on the establishment and/or dispersion of the predatory mite, after its release in the field. (AU)