Identification of weed species with allelopathic potential and characterization of their adverse effects against
associated crops is required for better understanding of weed-crop interactions. Phytotoxic activity of
Euphorbia dracunculoides
Lam. on germination and seedling growth of chickpea (
Cicer arietinum
L.) and wheat (
Triticum
aestivum
L.) was investigated under controlled conditions. Two separate studies were done with each of four
organic solvent fractions (n-hexane, chloroform, ethylacetate, 1-butanol) and crude aqueous (1:10 and 1:20) whole
plant fractions of
E. dracunculoides using distilled water and 0.05% (v/v) dimethyl sulfoxide (DMSO) as control.
Different aqueous and organic fractions of
E. dracunculoides had a significant bearing on germination attributes and
seedling growth that varied among tested species. The final germination percentage of wheat remained unaffected;
nevertheless, root and shoot elongation and biomass accumulation in these parts were significantly retarded. Aqueous
fractions appeared more phytotoxic than organic fractions and suppressed chickpea germination by 35-53%. These
aqueous fractions also reduced root (64-75% and 33-34%) and shoot (18-62% and 21%) length and root (32-33% and
42-46%) and shoot (7-32% and 80-84%) dry weight of wheat and chickpea, respectively. Among organic fractions,
n-hexane was more suppressive to test species. Chromatographic analysis revealed the presence of four phytotoxins,
furoic, p-coumaric, syringic, and caffeic acids, in aqueous whole plant (1:10) fractions. This study determined the
phytotoxic allelopathic activity of
E. dracunculoides against wheat and chickpea.
