The effects of aqueous extracts from maize roots and sorghum stem on the germination and radicle growth of Sphenosylis sternocarpa Hochst ex. Rich. (African Yam beans)

Abstract

The study examined the allelopathic effects of aqueous extracts from maize roots and sorghum stem on the germination and radicle growth of Sphenostylis sternocarpa (African Yam beans), an important cereal in southwestern Nigeria. The extracts from the two crop residues inhibited radicle growth of this crop. The degree of inhibition was concentration dependant as the inhibition increased with the increase in the concentrations of the extracts. The aqueous extracts derived from sorghum stem had more inhibitory effects as no radicle growth was recorded in the sorghum stem-extract treated seeds until 120hrs of the experiment. Statistical analysis (t-test, at 5% level) revealed that the inhibitions in sorghum extracts were not significantly different when the radicle lengths in the extract-treated seeds were compared to those in the control experiment. In the maize root-extract treated seeds, apart from the comparison of radicle lengths of seedlings in the 10g and 15g and between 10g and 20g extract concentrations that were significantly different, there were no significantly differences in the growth length of the radicles in the varying extract concentrations as well as those of the control experiment at 5% level.