Persistence of aldicarb and carbofuran residues in potatoes grown in northwestern plains of India

Abstract

Replicated field experiments were conducted during autumn 1982-83 at Jalandhar (Punjab) for evaluating an insecticidal schedule involving soil application of aldicarb (Temik) 10 G and carbofuran (Furadan) 3 G @ 1.0 and 1.5 kg a.i./ha in two different protocols viz.; (i) single full dose application of granules in furrows at planting and (ii) equal split dose application of granules (half in furrows at planting + remaining half dose near plants base at earthing up), found effective for aphid control, for residues. The findings indicate that aldicarb and carbofuran residues in unprocessed (unwashed, unboiled and unpeeled) potatoes from 1.0 and 1.5 kg a.i./ha doses applied in single full dose in furrows at planting (in the first protocol) persisted above the tolerance limits (0.50 ppm each for aldicarb and carbofuran) up to 70 days. Aldicarb residues in such unprocessed potatoes persisted above the tolerance limit up to 70/49 and 80/59 days respectively, from 1.0 and 1.5 kg a.i./ha doses when applied in two equal split doses at planting/earthing time. However, carbofuran residues in unprocessed potatoes were retained above the tolerance limit up to 70/49 days from both the doses applied in second protocol. At harvest, aldicarb residues in unprocessed potatoes were well within the tolerance limit from both the doses and protocols. On the other hand, carbofuran residues were undetectable from both the doses applied in the first protocol but were retained in traces (0.06 ppm) in unprocessed potatoes even from 1.0 kg a.i./ha dose applied in the second protocol. Residues of both the insecticides in processed (washed, boiled and peeled) potatoes and in water obtained after cooking the potatoes were below the tolerance limits in the beginning from both the doses and protocols which dissipated below the detectability level afterwards.