Dedifferentiation of leaf cells and growth pattern of calluses of capsicum frutescens cv. stromboli

In vitro cell suspension cultivation systems have been largely reported as safe and standardized methods of production of secondary metabolites with medicinal and agricultural interest. Capsicum frutescensis one of the most widely grown vegetable in the world and its biological activities have been demonstrated against insects, fungi, bacteria and other groups of organisms. The objective of this study was to establish a protocol for dedifferentiation of leaf cells of the cultivar C.frutescens cv. Stromboli and to determine the growth pattern of the calluses with a focus on the deceleration phase, when the callus cells must be subcultured into a liquid medium in order to establish cell suspension cultivations aiming at the production of secondary metabolites. The explants were inoculated into a medium supplemented with BA and 2,4-D in factorial combinations. The percentage of callus induction (%CI), the explant area covered by callus cells (ACCC) and the fresh weight of the calluses were evaluated. The procedures that resulted in higher proliferation of callus cells were repeated in order to determine the growth curve of the calluses. The treatment that resulted in the highest %CI, ACCC and callus weight was 1.5 mg L-1 2,4-D. The calluses produced were friable and whitish and their growth pattern followed a sigmoid shape. The deceleration phase started on the 39th day of cultivation.