Allelopathic Interference of Ageratum conyzoides L. against Rice Varieties

Kiran Bargali,Bhawna Negi,S.S Bargali,Kavita Khatri

doi:10.12944/carj.8.2.01

Abstract

Ageratum conyzoides L. is an invasive weed that has severely infested cultivated lands and interferes with the growth of crops. In this study aqueous extracts of 50 and 100% concentration were prepared from fresh and air dried plant parts (Leaves and roots) of A. conyzoides and their allelopathic effect was observed on seed germination and seedling growth of two rice varieties namely Sava and Geru. In Sava variety, a significant reduction in seed germination, seedling length and dry weight was recorded under dry leaf extract while under fresh leaf extract seed germination and seedling length was increased at 50% concentration as compared to control. In Geru variety both fresh and dry leaf extracts resulted in decreased seed germination and seedling growth with increasing concentration. Similar patterns were recorded for fresh and dry root extracts. The inhibitory effect of leaf extracts was more pronounced than root extract and overall dry aqueous extracts of leaf and root were more inhibitory than fresh aqueous extracts. Among varieties, Sava was least affected as compared to the Geru. This study indicated that A. conyzoides exert allelopathic effect towards rice crop by releasing water soluble phytochemicals.

Highlights

Ageratum conyzoides L. commonly known as billy goat weed is an alien weed species native of Central America and Mexico
Materials and Methods Preparation of Extract For preparation of fresh aqueous extract of leaf and root, green leaves and roots of A. conyzoides were collected from field and grounded to fine paste. 20 g paste of each plant part was soaked in 200 ml distilled water in 1:10 w/v at room temperature for 48 hours
The statistical analysis showed that aqueous extracts obtained from both leaf and root of A. conyzoides significantly affected germination and seedlings length of rice varieties in laboratory bioassay