Allelopathic potential of Cymbopogon citratus over beggarticks (Bidens sp.) germination

Abstract

Allelochemicals are important and innovative tools for weed control as they neither harm the environment nor increase weed management costs. The secondary metabolites can be extracted by water or soaking and later applied in soil or leaves. This study evaluated the leaf extracts of Cymbopogon citratus, affecting germination of Bidens pilosa and B. subalternans seeds. Two trials were conducted in germination chambers. The completely randomized design was employed in both trials with 5 replications. Trial one was arranged in a 2×3 double factorial design, with two periods of leave collection (morning and afternoon); and three extract preparations (aqueous extract by maceration, aqueous extract by infusion and control with distilled water). Trial two was set up in a 2×2×5 triple factorial design, with two extracts (aqueous extract by maceration, aqueous extract by infusion); two time of day collection (morning and afternoon) and five extracts concentrations (0; 25; 50; 75 and 100%). The means were compared by F and Tukey's test (p ≤ 0.05). To evaluate extracts concentrations a regression analysis was run. The results showed that the aqueous extract by maceration of C. citratus decreased germination and germination speed of Bidens pilosa and Bidens subalternans more than the aqueous extract by infusion, for both species. The concentrations interfered, inversely and proportionally, decreasing germination and germination speed. The germination of beggarticks was affected by the extracts of C. citratus, suggesting further studies for this plant.

Phytotoxic Potential and Phenolic Profile of Extracts from Scrophularia striata

“…The research revealed that the aqueous extract of C. citratus significantly reduced the seed germination rate of B. pilosa and B. subalternans . The concentrations interfered, inversely and proportionally, while reducing the germination rate [ 65 ]. A previous study was conducted on the phytotoxic potentials of aqueous leaf extracts obtained from Artemisia absinthium L. and Psidium guajava L. Evaluations were aimed at various effects on seed germination, plantlet development, enzymatic and non-enzymatic antioxidants, photosynthetic pigments, and osmolytes of Parthenium hysterophorus L. Leaf extracts of both A. absinthium and P. guajava acted to limit seed germination and plantlet development, but increased antioxidant enzyme activities [ 66 ].…”

Allelopathic influence of some fruit tree leaf extracts on germination and seedling development of different weeds and vegetable crops

“…3). Krenchinski et al (2017) carried out a similar study on the effect of Cymbopogon citratus extract on the germination and germination speed of beggartick. Reduced plant development will consequently affect carbohydrate concentration, as they are produced by the photosynthetic process (Currey and Lopez, 2015).…”

“…Regarding competition, allelopathy is an important mechanism in which plants release chemical compounds named allelochemicals (Sharokhi et al, 2011). Allelochemicals can cause direct or indirect and positive or negative results to other plants and organisms (Krenchinski et al, 2017). By releasing the allelochemicals, plants can inhibit the germination and development of other species.…”

Herbicide activity of natural compounds from Baccharis spp Herbicidal activity of natural compounds from Baccharis spp. on the germination and seedlings growth of Lactuca sativa and Bidens pilosa

“…Concerning seed germination, Hanley and Whiting (25) reported that phytotoxic allelochemicals present in the extracts appear to mediate a disruption of normal cellular metabolism, affecting reserve mobilization, a process that usually takes place during early stages of seed germination (23). The aqueous extracts of Cymbopogon citratus were allelopathic to germination of Bidens pilosa and B. subalternans (33).…”