Allelopathic Potential of Hesperozygis ringens Extracts on Seed Germination of Soybeans and Beggarticks

Abstract

Hesperozygis ringens L., popularly known as espanta-pulga, is a native shrub found in rocky fields in Rio Grande do Sul. Its leaves produce a lot of essential oil, which contains pulegone as a main component that may be allelopathic. The objectives of this study were to analyze the allelopathic effects of H. ringens leaf extracts on the germination and initial development of soybean seeds and to evaluate the herbicidal potential of these extracts on beggarticks (Bidens pilosa L.). The seeds were placed on paper embedded in an aqueous extract of H. ringens leaves at concentrations of 0, 25, 50, 75 and 100% and maintained in a germination chamber at 25 °C and a photoperiod of 12 h. The tests included the following: germination, first germination count, germination speed index, and length and dry mass of seedlings. The experimental design was completely randomized. Based on the results, the aqueous extracts of Hesperozygis ringens leaves had a detrimental effect on the germination and seedling growth of the soybeans and beggarticks, evidencing their allelopathic action.

Allelopathic activity of Manihot esculenta crantz on the germination of Avena sativa L. and Trifolium resupinatum L. Seeds

“…To carry out the experiments, the leaves of Manihot esculenta collected in the afternoon were initially dried in an oven and ground in a blender for approximately 2 minutes at the rate of 10 g of dry leaves to 100 mL of distilled water, which was considered the 100% (p/v) crude extract, adapted from Lima et al (2020). The mixture remained at rest for 24 hours (in the dark and refrigerated at 5 ºC) and was then filtered through filter paper.…”

Seed germination of Hesperozygis ringens (Benth.) Epling, an endemic and threatened species

“…For Hesperozygis ringens, some studies describe a high production of essential oil by the leaves, with pulegone (95.18%) as the principal component (Silva et al, 2014). The essential oil of this species has high antioxidant (Dolwitsch et al, 2020), antiparasitic and antimicrobial (Bandeira et al, 2017), alellopathic (Pinheiro et al, 2016;Lima, Lima, Birck, & Stefanello, 2020), and anesthetic and larvicide action (Silva et al, 2014). Additionally, in a pioneering work about in vitro cytotoxicity and genotoxicity, Dolwitsch et al (2020) demonstrated that its UAE-EtOH and SFE-CO 2 extracts are safe for human lymphocytes at the concentrations evaluated.…”