Vol. 14 No. 1
Bioassay for the detection of penoxsulam + cyhalofop butyl residue in soil
Author(s): S. K. RAJ AND E. K. SYRIAC
Abstract: Bioassay tests were carried out at Department of Agronomy, College of Agriculture Vellayani during 2014 and field experiments were carried out during kharif 2014 and rabi 2014-15 in farmers field at Kalliyoor Panchayat of Thiruvananthapuram district, Kerala. Response of three test crops, maize, cucumber and sunflower to penoxsulam + cyhalofop butyl revealed that maize was the most sensitive indicator plant and fresh shoot weight of maize was the most susceptible parameter to detect the phytotoxic residue of this herbicide in soil. Bioassay with maize plant in post experiment soil during both the seasons revealed that post emergence application of penoxsulam + cyhalofop even at a concentration of 135 g ha-1 did not cause any growth inhibition in fresh shoot and dry weight, shoot length and root length inferring that, the herbicide penoxsulam + cyhalofop butyl 6 % OD (oil dispersion) did not leave any phytotoxic residue in soil and is environmentally safe.