Pequi leaves incorporated into the soil reduce the initial growth of cultivated, invasive and native species.

Studies have identified the phytotoxicity of many native species of the Cerrado; however, most of them were conducted either in inert substrates, or using exaggerate proportions of plant material. We investigated the phytotoxicity of pequi leaves added to substrate soil in quantities compatible with the litter produced by this species. Pequi leaves were triturated and added to red latosol in concentrations of 0.75%, 1.5% and 3%; the control was constituted of leafless soil. These mixtures were added to pots and irrigated daily to keep them moist. Germinated seeds of the cultivated sorghum and sesame, of the invasive brachiaria and of the native purple ipê, were disposed in the pots to grow for five to seven days at 30°C within a photoperiod of 12 h. Seedlings of all the species presented a reduction in their initial growth in a dose-dependent way. In general, the root growth was more affected by the treatments than the shoot growth; moreover, signs of necrosis were observed in the roots of the sorghum, sesame and brachiaria. The phytotoxic effects generated by relatively small quantities of leaves, in a reasonable range of species within a soil substrate, suggest potential allelopathy of pequi leaves under natural conditions.

Evaluation of embryotoxic and teratogenic effects of the oil extracted from Caryocar brasiliense Cambess pulp in rats.

The objective of this study was to evaluate the maternal, embryotoxic and teratogenic effects of Caryocar brasiliense pulp oil (OPCB), oil widely used in Brazilian cuisine and traditional medicine. Pregnant Wistar female rats were used in this study for three treatment groups (250, 500 and 1000 mg/kg/day) and a control group. The OPCB was administered orally throughout the period of organogenesis of females (6th until the 15th day of gestation). The pregnant females were gross necropsied on d20, followed by maternal and fetus examination, to evaluate the teratogenicity, reproductive and developmental performance of OPCB. The results showed there was no significant statistical difference in the ponderal evolution of the pregnant females, as well as in the behavioral, hematological, biochemical or histopathological data, indicating the absence of maternal toxicity of the oil. The mean number of corpora lutea, implantation and resorption sites, as well as all calculated reproductive rates, also remained statistically similar between the groups, indicating low embryotoxic effects of the tested plant specie. In fetal examination, external anomalies and skeletal abnormalities were observed in all treated and control groups. The NOAEL for maternal toxicity and embryo/fetal development for the OPCB administered by gavage, was 1000 mg/kg/bw/day.