[The effect of 2 diets on the biological aspects of Blattella germanica (Dictyoptera: Blattellidae) under laboratory conditions].

It was conducted a study of 2 colonies of Blattella germanica (Dictyoptera: Blattellidae) kept since 1994 in the laboratory at 29 +/- 1 degrees C, 70-75% of relative humidity and with different foods: one on a diet without proteins, consisting in portions of potatoes (Solanum tuberosum, L.), ripe banana (Musa paradisiaca, L.) and a sugary solution 10%, and the other with a protein content of 20.45% composed of pulverized and dry laboratory food for rats and a source of water. 6 nymphal stages were found with both types of food. There were determined the times of interchanges and the time of nymphal development, which were much shorter among the nymphs fed with proteins. The longevity of each sex showed no significant differences in connection with the type of food used. The times of appearance and eclosion of the oothecae of each oothecal cycle were determined with both foods. It was found that the females deposited up to 5 oothecae during their lives with the 2 types of diet. The average of nymphs per ootheca among the females fed with proteins was much greater (t = 5.33; p < 0.001). The results of this study show that when the food for B. germanica contains proteins, its nymphal development is faster and its reproductive capacity increases, which means that protein is a necessary nutrient for the diet of this species.