Screening the Allelopathic Activity of 14 Medicinal Plants from Northern Thailand

Abstract

Fourteen medicinal plants from northern Thailand, which dominate and form large colonies, were dried, powdered, and evaluated for growth inhibitory activity using a modified sandwich method. All the plants showed inhibitory activities on the growth of lettuce seedlings: Cymbopogon nardus had the strongest activity, completely inhibiting the growth of the lettuce hypocotyls and radicles; Piper retrofractum completely inhibited the hypocotyl growth and 93.5% of the radicle growth; and the remaining plants inhibited hypocotyl and radicle growth by 30.9 57.4% and 44.1 75.3%, respectively. Inhibitory active compounds may have been released from the plants into the sandwich method medium and inhibited the growth of the lettuce seedlings. The present results suggest that C. nardus and P. retrofractum are possible candidates for developing alternative natural herbicides in sustainable agriculture because of their strong inhibitory activity.

Comparative Evaluation of the Allelopathic Effects of the Leaf Extracts of Three Asteraceae Species (Ageratum conyzoides, Vernonia amygdalina, Artemisia annua)

“…To demonstrate allelopathy, plant origin, production and identification of allelochemicals as well as persistence in the environment over time in concentrations sufficient to affect plant species is first established [7]. This is carried out in the laboratory by screening plant extracts and leachates for their effects on seed germination with further isolation and identification of allelochemicals from green house tests [8].…”

PLANTAS MEDICINAIS E AROMÁTICAS DO ESPÍRITO SANTO: O ÓLEO ESSENCIAL DE FOLHAS E FRUTOS DA ESPÉCIE Schinus terebinthifolia RADDI (AROEIRA VERMELHA)

“…A alelopatia é um fenômeno de interações químicas entre as plantas, no qual os aleloquímicos são produtos químicos liberados pelas plantas para o meio ambiente via volatilização, exsudação das raízes, lixiviação e decomposição de plantas (SUWITCHAYANON et al, 2017). Os aleloquímicos podem representar uma influência nociva ou benéfica, uma vez que podem inibir ou estimular a germinação e o crescimento das espécies receptoras desses aleloquímicos (BALIČEVIĆ et al, 2016).…”

Phytotoxic potential of selected medicinal plants on germination of Lactuca sativa seeds

“…These plants use in present study are commonly used for treating various illnesses but their allelopathic potentials are not reported yet. It is reported that medicinal plants can also be good sources of novel herbicides by inhibiting the growth seeds in vivo [31,32]. It revealed from previous work that medicinal plants can produce inhibitory allelochemicals which reduces the germination of weeds [33].…”