Abstract

The aim of this work is to evaluate the main biological aspects of P. includens fed on four cotton cultivar leaves and to study the effect of the transgenic cultivar NuOPAL (Bollgard I^®) which express the protein Cry1Ac on the survival and development of the insect, Pseudoplusia includens. Two assays were carried out using the completely randomized blocks design. The former was represented by the cultivars DeltaOPAL, NuOPAL, FMX 993 and FMX 910 used for feeding the insect larvae, and the latter assay, only the cultivar NuOPAL and its conventional isoline DeltaOPAL were used for larvae rearing, with a higher larvae population. The leaves were obtained from cotton plants cultivated in the field and placed in Petri dishes where neonate larvae were individualized and fed daily with the respective cultivars. The following biological parameters were evaluated: duration period, weight and viability of larvae and pupae, duration and viability of larva-pupa-adult period, longevity of adults and sex ratio. Bt cultivar (Bollgard I) suppressed the half of larval population, extends the larval stage of the survivors, reduced the larvae and pupae weights and provides significantly higher duration of larva-adult period.

Key words: Soybean looper, Gossypium hirsutum, Bt cotton, genetically modified organisms (GMO), Cry1Ac.