Modeling the spatial and temporal location of refugia to manage resistance in Bt transgenic crops

摘要: Abstract The present paper explores the use of refugia in high dose-refugia resistance management strategy for Bacillus thuringiensis (Bt) transgenic crops. model used represents a patchy population an insect pest which recessive is conferred by single locus with two alleles. frequency allele between generations was based on selection intensity, fitness cost, percentage refugia, mortality due to insecticide sprays, initial and rate movement. simulation run using four different spatial patterns inside field crop (border, central, equidistant random), rotation patterns, five sizes refuge (5–50%), levels non-Bt efficacy plus untreated control refugia. It found that: (a) greater size lower increase resistance, (b) positioning patches at random resulted higher compared non-random positions, (c) border central (d) increased markedly when refugium less than 10%, (e) temporal (rotation host crop) led decline allele, (f) rates movements (g) also sprayed insecticide. Possible mechanisms optimize are discussed.