Abstract
The translocation and metabolism of oxamyl and carbofuran were investigated in tomato plants under plastic houses conditions. The producing plants were treated with 20 kg/ Feddan of the 10% granules of either oxamyl or carbofuran. Data explained that both compounds transferred from the roots of tomato plants to their fruits. The concentrations of oxamyl reached 33.4 ppb in tomato fruits after one day following application. This amount increased with time to reach 123.5 ppb after 10 days and at the end of experiment (21 days) declined to be 51.1 ppb. On the other hand, The absorbed amounts of carbofuran reached 312.9 ppb in tomato fruits after one day following treatment. This value increased with time and after 10 days reached at 1003 ppb. At the end of experiment (21 days ) carbofuran amount declined to 130.1 ppb in tomato fruits. The average recoveries of oxamyl and carbofuran from tomato fruits at various spiking levels were 82.6 and 80.2 %, respectively. Oxamyl was metabolized to oximino oxamyl. The amount of this metabolite reached 569.5 ppb in tomato fruits after one day and then heightened to 609.9 ppb after 3 day. Oximino oxamyl amount dropped with time to rerach 184.8 ppb after 10 days and then the amount increased again to arrive 300.1 ppb at the end of experiment (21 days). On the other side, carbofuran was slightly metabolized to 3-hydroxycarbofuran and 3-ketocarbofuran phenol. The levels of 3-hydroxycarbofuran was greater than 3-ketocarbofuran phenol at all times following application. The results indicated that the translocation and persistence of carbofuran was greater than oxamyl in tomato plants.