Studies on the residues of phosalone on chilli by GLC after multiband plate cleanup.

Four sprays of 0.05 and 0.10% phosalone were given on chilli (Capsicum annuum Linn.) crop at an interval of 15 days starting from 21 days after transplanting. Residues were determined in the green chilli fruits by GLC after cleanup of extract on multiband thin-layer plate. The half-lives of residues were 1.55 and 1.68 days on chilli fruits from the crop treated with four sprays of 0.05 and 0.10% phosalone respectively. The time required to reach the tolerance limit of 1 ppm after last spray with 0.05 and 0.10% emulsion was 4.75 and 7.62 days respectively. Washing of fruits under tap water was found effective in bringing down the level of phosalone residue by 21.64 to 75.11%.

Gas-liquid chromatographic studies on residues of endosulfan on chilli fruits.

Studies on the residues of endosulfan were undertaken by GLC so as observe the dissipation of endosulfan and its isomers on green fruits of chilli, Capsicum annuum Linn. and also to know the effect of washing the fruits on the residues. The pattern of dissipation of endosulfan was conventional showing half-life less than two days. The waiting periods worked out were 5 and 7 days after protecting the crop with four sprays of 0.03 and 0.08% endosulfan respectively. The dissipation of alpha isomer was found faster than that of beta isomer. Washing of fruits from treated crop was found quite effective in reducing the level of residues on the fruits.