Lasioderma serricorne (F.) is a small cosmopolitan beetle regarded as a destructive pest of several stored products such as grains, flour, spices, dried fruit and tobacco. Chemical insecticides are one of the measures used against the pest. However, intensive insecticide use has resulted in the appearance of resistant insect populations. Therefore, for the elaboration of more effective control programs, it is necessary to know the biological aspects of L. serricorne. Among these aspects, the genetic variability knowledge is very important and may help in the development of new control methods. The objective of this study was to evaluate the genetic variability of 11 natural populations of L. serricorne collected respectively in three and four towns in the states of Paraná and São Paulo, Brazil, using 20 primers random amplified polymorphic DNA (RAPD) and polymorphisms of esterases. These primers produced 352 polymorphic bands. Electrophoretic analysis of esterases allowed the identification of four polymorphic loci (Est-2, Est-4, Est-5 and Est-6) and 18 alleles. Results show that populations are genetically differentiated and there is a high level of genetic variability within populations. The high degree of genetic differentiation is not directly correlated to geographical distance. Thus, our data indicate that movement of infested commodities may contribute to the dissemination of L. serricorne, facilitating gene flow.

The cigarette beetle Lasioderma serricorne through transportation affects the infestation of stored tobacco. Using amplified fragment length polymorphism (AFLP), DNA polymorphisms were assessed in 16 populations of L. serricorne collected from 15 countries. The dendrograms constructed from profile distance matrices revealed well-supported colony clusters. There was no clear clustering as a function of the geographic origin of the samples. The results suggest extensive insect dispersal among geographical regions due to movement of infested commodities worldwide. This first AFLP population study of a stored-product insect demonstrates the potential of AFLP for distinguishing L. serricorne populations.

The length of the reproduction cycle of Lasioderma serricorne (F.) under ambient laboratory conditions (temperature range 28.0–32°C and 72.5–80.5% r.h.)was shown to depend on the identity and state of division of various cereal grains, cowpeas, groundnuts and dried root crops. Cut dried yams allowed the shortest cycle andwholericethelongest.The rate of population increase by L. serricorne was also assessed and this was maximal when cut wheat and minimal when whole rice was provided. Fecundity was highest with sorghum and lowest with rice as food source. Females of the species lived longer than males.