Allelopathic Potential of Lantana camara (L.) and Parthenium hysterophorus (L.) Weeds on Germination and Growth Behaviour of Thespesia populnea (L.)

Abstract

A Pot culture experiment under green house condition was conducted to study the allelopathic effect of Lantana camara (L.) and Parthenium hysterophorus (L.) weeds on germination and growth behaviour of Thespesia populnea (L.) tree species. The experiment was laid out in Randomized Complete Block Design (RCBD) and replicated thrice. Combination of two invasive weed species viz., Lantana camara and Parthenium hysterophorus) and four concentration levels of aqueous extract viz., 10, 20, 30 and 40% were assigned as main treatments with application of normal water as control. The results revealed that, application of whole plant aqueous extract of Parthenium hysterophorus at higher (40%) concentration significantly recorded lower seed germination percentage (26.7), germination value (3.0), germination index (0.14), germination relative index (5.7) in Thespesia species than at lower concentration of Parthenium hysterophorus and Lantana cam ara weed species. Whereas, number of days required for the germination of Thespesia seed was maximum (9.05 days) in application of aqueous extract of Parthenium hysterophorus at 40% concentration. Thespesia seedlings growth and growth behaviour were also significantly inhibited by the whole plant aqueous extract of Parthenium weed at higher concentration, which reduced shoot length (12.6cm), root length (9.2cm), dry weight (12.6 mg plant1), dry weight based vigour index (338) and chlorophyll content (15.7 pmol chlorophyll nr2) at 60 days after sowing.