Leaching from leaves of Sarcomphalus joazeiro and Cenostigma bracteosum stimulate or inhibit the germination of Mimosa caesalpiniifolia?

Abstract

Allelopathy is an ecological mechanism that influences the development of neighboring plants. The objective was to evaluate the allelopathic potential of Cenostigma bracteosum and Sarcomphalus joazeiro on seed germination and initial growth of Mimosa caesalpiniifolia seedlings. Seeds of this species were placed to germinate on paper towel substrate, and then moistened with extracts from dry leaf of S. joazeiro and C. bracteosum at 1.0; 2.5; 5.0 and 10.0% (w.v-1), and control (0.0% - distilled water) at 25 °C. The variables evaluated: germination, germination speed index, primary root length and root system dry weight of the seedlings. Positive allelopathic effects of S. joazeiro leaf extracts were observed on the vigor of M. caesalpiniifolia; when used in low concentrations (up to 2.6%), C. bracteosum leaf extracts stimulated germination of M. caesalpiniifolia seeds and showed more severe toxic effects when exposed to high concentrations (5.0%). S. joazeiro leaf extracts favor the germination and vigor of M. caesalpiniifolia seedlings, while C. bracteosum leaf extracts cause phytotoxic effects on seed germination and initial growth of M. caesalpiniifolia seedlings from the concentration of 5%. Therefore, there are indications of benefits for regeneration or associated forest composition between M. caesalpiniifolia and S. joazeiro.

Allelopathic activity of Piptadenia moniliformis Benth. on the physiological potential of seeds of Amburana cearensis Allem.

“…Pacheco et al (2017) [21], using aqueous extract of Pityrocarpa moniliformis observed that although there was no influence of extract concentrations on the germination percentage of Mimosa caesalpiniifolia, observed that the germination process speed decreased sharply as the concentration of leaf extract increased, while the extracts of the fruits provided little significant reduction. Furthermore, Araújo et al (2021) [22] observed deleterious effects of Cenostigma bracteosum leaf extracts, from the concentration of 5%. on seed germination and seedling vigor of Mimosa caesalpiniifolia.…”

“…Including, not only the negative effects of allelopathy, but also the beneficial ones, such as stimulating the germination process and/or the establishment of seedlings. Within this context, it was observed that the germination and vigor of Mimosa caesalpiniifolia seedlings were favored by the extracts of leaves of Sarcomphalus joazeiro [22], denoting a positive influence of allelopathy. [31] highlight the importance of developing research on allelopathic interactions between native tree species in the Caatinga (forest and/or fruit trees), aiming to determine synergistic species that can favor the recovery of degraded areas and sustainable management.…”