Allelopathic potential of Sapindus mukorossi Gaertn tested against Pennisetum Americanum (L.) leeke,Setaria Italica (L.) Beauv. and Lactuca sativa L

Sapindus mukorossi gaertn,locally named as soap nut tree is a deciduous plant reaching up to the 20 m height. present study is designed to investigate allelopathic potential of s. mukorusii through its aqueous extracts against pennisetum americanum (l.) k. schum.,setaria italica (l.) p. beauv. and lactuca sativa l. the effect of aqueous extracts of leaves and fruits in different concentration (5%,10%),hot water extracts,soil intoxication and litter was observed on germination,fresh and dry weight,moisture content and overall growth of test species. plant extracts significantly inhibit germination rate and overall growth of all the test species. activity of extract were found dependent on concentration and soaking duration of extract,thus highest activities were recorded for extracts with 10% concentration with 72 hours soaking duration. l. sativa was found most susceptible in regard of germination. plumule length of s. italica was most inhibited. the effect of both cold and hot water extracts showed maximum activities against the radicle lengths of s. italiccertaina and p. americanum while l. sativa was found least susceptible. soil intoxication and letter showed maximum inhibitory activity against the l. sativa. the study thus reveals that the s. mukorusii is significantly allelopathic to towards the test species and inhibits both their germination and overall growth. © 2015,pakistan botanical society. all rights reserved.