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The persistence of dimethoate and demeton-methyl, which are recommended for control of the pea leaf-miner [?Phytomyza horticola Goureau], in and on pea pods and their movement into the fruits was studied in Haryana, India, during the rabi (cool) season of 1978-79. Dimethoate was applied at 300 and demeton-methyl at 315 ml a.i./ha as a foliar spray after 50% pod formation and twice more at intervals of 15 days. The initial residues, analysed by spectrophotometry, 12.72 and 20.68 in pods and fruits, respectively, treated with dimethoate, and 13.04 and 13.50 p.p.m. in pods and fruits treated with demeton-methyl. The dimethoate residue fell below the tolerance level within 10 days after the last spraying, while the demeton-methyl residue took 21 days. When fruit samples were analysed 30 days after harvest (51 days after the last treatment), the residues of both compounds had fallen below a detectable …