Biologia comparada e comportamento de Tetranychus urticae Koch (Acari: Tetranychidae) e Phytoseiulus macropilis (Banks) (Acari: Phytoseiidae) em algodoeiro bollgardTM e Isolinha não-Transgênica

Abstract

Compared Biology and Behavior of Tetranychus urticae Koch (Acari: Tetranychidae) and Phytoseiulus macropilis (Banks) (Acari: Phytoseiidae) on Bollgard TM and non-Transgenic Isoline Cotton ABSTRACT -The two spotted spider mite, Tetranychus urticae Koch, is a nontarget herbivore of Bt-cotton, but acquires and accumulates higher levels of Cry toxin than that expressed by transgenic plants. This work investigated the development and reproduction of T. urticae and of the predator Phytoseiulus macropilis Banks, during three successive generations looking for potential nontarget effect. In addition, behavioral studies on feeding preference, oviposition, and predation were carried out on Bt and non-Bt cottons. The development and reproduction of T. urticae and P. macropilis was conducted using leaf discs of Bt and non-Bt cottons. Arena containing leaf discs from both cotton types connected by a slide coverslip were also used in the behavioral studies. Averages of the three generations showed that the Bt-cotton does not affect the development, survival of immature stages, and reproductive output of T. urticae and of the predator P. macropilis. Furthermore, the preference for feeding and oviposition of T. urticae and P. macropilis were similar on both cotton types. In addition, P. macropilis exhibited similar predatory behavior on T. urticae fed on both cotton types. Levels of Cry1Ac toxin in T. urticae was 3.97 times greater than that found in the Bt-cotton plants as determined using a ELISA test. Despite of the amount of toxin acquired by the prey (T. urticae), no detectable levels of Cry1Ac were found in the predatory mite P. macropilis.

DEVELOPMENT OF Tetranychus urticae KOCH (ACARI: TETRANYCHIDAE) IN DIFFERENT STRAWBERRY CULTIVARS

“…moro et al (2012) analyzed the duration of the developmental period of T. urticae in papaya cultivars and observed variation in the duration of the egg-adult period between 9.4 and 10.2 days. Silva et al (1985) and esteves Filho et al (2010), in similar works in cotton cultivars, observed duration in the egg-adult period between 10.6 and 10.7 days, and 8.9 and 9.3 days, respectively. the greater prolongation of immature stages and the lower survival at this stage are generally related to the chemical or nutritional characteristics of the host, in which prolongation is caused by a condition unfavorable to the individual development, and acceleration, on the contrary, shows that the host meets nutritional needs to quickly reach the adult stage.…”

Toxicidade de espiromesifeno e acaricidas naturais para Tetranychus urticae koch e compatibilidade com Phytoseiulus macropilis (Banks)

“…Em pepino e morangueiro (WATANABE et al, 1994;GONÇALVES, 2007) observou-se a sua predação sobre T. urticae; também apresenta potencial para ser usado no controle biológico desta praga em algodoeiro (ESTEVES FILHO et al, 2010). Fato este justificado pelo hábito alimentar deste predador que, de acordo com Mcmurtry e Croft (1997) é especializado na predação de ácaros do gênero Tetranychus.…”

Effects of Bt+CpTI transgenic cotton on the performance of <em>Tetranychus</em><em> turkestani</em> (Acari: Tetranychidae)

“…However, our results indicated females reared on transgenic or non-transgenic cotton showed no difference in either development or fecundity. Similarly, transgenic crops (cotton and maize) in two others studies had no effect on the development, survival, or reproduction of T. urticae (Esteves, 2010;Li and Romeis, 2010). Dutton (2002) and Lozzia et al (2000) reported no difference in the intrinsic rate of natural increase of T. urticae reared on Bt or non-transgenic plants.…”