Pennisetum glaucum AQUEOUS EXTRACT SUPPRESSES GROWTH OF SOME WEED SPECIES

Abstract

A laboratory study was conducted to investigate the allelopathic effects of aqueous extract of Pennisetum glaucum on different noxious weed species i.e., signal grass (Brachiaria reptans), common lambsquarters (Chenopodium album), field bindweed (Convolvulus arvensis), broadleaf dock (Rumex dentatus), jungle rice (Echinochloa colona), slender amaranth (Amaranthus viridis), snake cucumber (Cucumis melo var. agrestis) and milk thistle (Sonchus asper). Five different concentrations (25, 30, 35, 40, 45 g/L) of pearl millet aqueous extract along with control (distill water) were used to decipher its efficacy on aforementioned weed species. Various parameters were studied including germination (%), root and shoot length, root and shoot weight and plant fresh weight. The study revealed very strong phytotoxic effects of millet aqueous extract on all the studied parameters when applied at 45 g L^-1, whereas use of 25 g L^-1 aqueous extract was found less effective compared with control showing some stimulation in plant growth. Milk thistle (Sonchus asper) and snake cucumber (Cucumis melo) were most susceptible, whereas signal grass (Brachiaria reptans) was resistant to aqueous extract of pearl millet. The data indicated that aqueous extract of pearl millet  has inhibitory effects on weeds growth at higher concentrations (45 g L^-1). Further research is suggested to fine tune the efficacy of pearl millet extract for their commercial utilization in weed management.