Germination and Early Seedling Growth of Two Rice Varieties as Affected by Invasive Ageratina adenophora

Abstract

Ageratina adenophora is a perennial herb of family Asteraceae expanding as a serious threat to ecological integrity and biodiversity. This study aims to assess the allelopathic potential of fresh and dry leaf and root aqueous extracts of this invasive species on germination, early seedling growth, seedling biomass and seed vigor of two rice (Oryza sativa L.) varieties namely 6444 and 2245. The result revealed that with increasing concentration of extract, inhibition effect also increases. Leaf extract was more inhibitory than root extract and dry plant extracts had higher allelopathic impact in comparison to fresh plant extracts. Among the two investigated rice varieties 6444 was more resistant to the fresh and dry leaf extract while 2245 was more resistant to fresh and dry root extract. This study will be helpful in assessing the effect caused by A. adenophora to rice crop and could be used in devising weed control strategy.