Bioefficacy, phytotoxicity and terminal residues of atrazine applied in Potato (Solanum tuberosum) crop

摘要

A field experiment was conducted in the farm of division of Agronomy at CSKHPKV Palampur, Himachal Pradesh to determine residual fate of atrazine applied as pre-emergence at four doses 0.5 kgha~(-1), l.Okgha~(-1), 1.5kgha"'and 2.0 kgha~(-1) in potatocrop. Atrazine 1.5 kgha~(-1) being at par with atrazine 2.0 kgha 1 and paraquat 0.6 kgha~(-1) recorded significantly lower count and dry matter of total weeds which were as effective as hand weeding twice, thereby contributing in getting significantly higher tuber yield during both the years. The presence of the weeds in unweeded check resulted in 65.4 to 56.0% of yield losses, during respective years.Soil samples and potato tuber samples at the maturity of crop were collected, processed and subjected to atrazine residue analysis by a validated gas chromatography method with an accepted recovery more than 80%. Atrazine residues in soil and potato tubers at the time of harvest were below detectable levels (0.05 ug g"'). This indicated that the atrazinedid not leave any residues in potato tuber at any of the applied doses. From the study, it may be concluded that pre emergence application of atrazine in potato for weed management could be considered safe, as its residues were below the prescribed MRL value 0.05 mgkg1.