RESUMEN
Brevipalpus yothersi Baker (Acari: Tenuipalpidae) was recently confirmed as one of the main vectors of citrus leprosis. Knowledge about this mite's biology is essential to understand its population dynamics, in order to solve management issues in citrus orchards and explain why citrus leprosis is more severe in some regions. This paper aimed to study biological factors affecting prevailing population levels of B. yothersi and incidence of citrus leprosis. Mites were sampled from orchards in the south, north and northwestern regions of São Paulo State, Brazil. We assessed duration of the developmental stages, oviposition, incubation period, egg viability, longevity, net reproductive rate (Ro), mean generation time (T), intrinsic rate of increase (rm) and finite rate of increase (λ). There were small differences in parameter values between the three populations. Our results indicated that the various measures adopted in the control of the three populations did not lead to major biological differences between populations for the evaluated parameters.