1Tea Research Association, 113 Park Street, Kolkata, 700 016
2Pesticide Residue Laboratory Department of Agricultural Chemicals, Bidhan Chandra Krishi Viswavidyalaya, Mohanpure-741252, W.B., India
*Corresponding author E-mail: anjan_84@rediffmail.com
Online published on 10 November, 2011.
Dissipation of a new post emergence herbicide, bispyribac sodium technical standard (97% purity) and formulation (10% SC) was studied under three types of water i.e. pH - 4.0, 7.0, 9. Water (200 mL) each of three pH type after fortification with 1, 2 µg mL−1 of technical standard and formulation was extracted and analyzed by HPLC coupled with UV/VIS detector. Dissipation follows first order reaction kinetics irrespective of standard type, treatment doses and pH type. Calculated half life values in technical grade as well as in formulation shows that stability of bispyribac sodium is lowest at acidic pH (24 -26 days) as compared to neutral pH (30–33 days) and alkaline pH (37–42 days).
Bispyribac sodium, pH, dissipation kinetics
