DISSIPATION OF ATRAZINE IN ALFISOLS AND SWEET CORN

Abstract

A field experiment was conducted in the College Farm, Rajendranagar, Hyderabad to study the persistence in
soils and residual effects of atrazine in sweet corn during rainy season (Kharif) 2012 and 2013. Atrazine was
applied as pre-emergence and post-emergence spray at two levels (1.0 and 2.0 kg/ha) and persistence was studied
in soils (0, 10, 30, 45, 60 days after application, DAA, and harvest), maize grain/stover at harvest. Atrazine residue
were determined using GC-NPD. In pre-emergence treatments, atrazine residues persisted in the soil upto 60
DAA at 1.0 and 2.0 kg/ha dose of application during both years. Atrazine residues concentration in the soil was
lower in post-emergence treatments and residues persisted upto 45 DAA during two years at 1.0 kg and 2.0 kg/
ha application rates. Residues of atrazine in sweet corn grain and stover were below the detection during two
years at two rates of application. Atrazine persistence insoil followed first order kinetics with half-life varying
from 26.45 days to 35.77 days. Atrazine can be safely applied to sweet corn as the grain and stover residues were
below the MRL values.