Phytotoxicity and cytogenotoxicity of Dionaea muscipula Ellis extracts and its major compound against Lactuca sativa and Allium cepa.

Plants are rich in active compounds, which can have an effect on the growth of other plants. In this context, the present work aimed to evaluate the effect of dichloromethanolic extracts from fresh and dried plants of Dionaea muscipula and compare it with its major compound in Lactuca sativa and Allium cepa. For this end, we conducted biological assays, determining the effects on germination, early development and cell cycle in plantlets and meristematic cells of L. sativa and A. cepa. The major compound identified by GC-EM was plumbagin with 89.71% in fresh plants and 53.13% in dry plants. The growth curves revealed the concentrations of 305,5; 538,4 and 32,08 μg mL−1 for fresh, dried and plumbagin, respectively, as those reducing 50% of germination %. And A. cepa with IC50: 279,3; 552,7 and 11,68 μg mL−1, respectively. Treatment with both extracts affected seedling growth (root and shoot) similarly to glyphosate, but only in L. sativa. Glyphosate did not affect the growth of A. cepa, which was observed in the extracts and plumbagin. Extracts at 1600, 800, and 400 μg mL−1 proved to be good options for pre-emergence control, while concentrations of 800, 400, and 200 μg mL−1 caused cell-cycle changes that compromised seedling viability in late development. Chromosome stickiness was the most frequent and did not indicate the mechanism of genotoxicity of the extracts, but the high prevalence of condensed nuclei suggests that cytotoxicity occurred with the activation of apoptotic pathways, common to naphthoquinones. This suggests that D. muscipula extracts are toxic to plants due to the availability of plumbagin, and they have the potential of use, affecting from seed germination to the early development of L. sativa and A. cepa. [ABSTRACT FROM AUTHOR]