Allelopathic Interaction Studies on Parthenium hysterophorus L.

Abstract

The increase in concentration of allelochemicals, both from plant and seeds of Parthenium, caused decrease in the germination of Raphanus seeds. The seed germination was inhibited up to 100% in the presence of Plant diffusates (PD) and up to 86.66% in the presence of seed diffusates (SD). These allelochemicals also reduced the glucose level in germinating seeds of Raphanus sativus. The glucose level reduced up to 55% in 100 % PD grown seeds and up to 37% in 100% SD grown seeds.

Extracts (essential oils) from Eucalyptus citriodora, Cymbopogon citratus and Cinnamomum camphora were used to analyze their effects in germination and seedling development of the weed. Cymbopogon oil at 8 ml l-1, Eucalyptus and Cinnamomum oils at 12 ml l-1 and all above concentrations of all extracts arrested the seed germination of the weed completely. The oil extracts irrespective from their sources were found significantly effective (P < 0.05) in arresting the seed germination and seedling length of Parthenium hysterophorus in laboratory conditions.