| Tebuconazole and tebuconazole·thiram were selected to controling wheatdiseases in course of enviormentally and harmless high and quality wheatproduction. In this paper, It were studied that the analysis of 40%tebuconazole·thiram WP and the residue dynamics of tebuconazole, thiram,tebuconazole·thiram in wheat and the effect of tebuconazole on the populationand the respiration of the soil microbes. The results could be summarized asfollowings:1. A reversed phase high performance liquid chromatography (RPHPLC)was proposed for the determination of the tebuconazole and the thiram in 40%tebuconazole·thiram WP. In this method, methanol and water(85/15,V/V)admixture was used as a mobile phase, the tebuconazole and the thiram wereseparated by a reversed phase C18 column and they were detected by anUV-detection at 221nm. The recovery of the tebuconazole and the thiramrespectively was 99.68% and 99.24%,their C.V. was 1.10% and 0.65% andtheir correlation coefficient was 0.9993 and 0.9994.2. A residue analytical method was set up for analysis tebuconazole inwheat. The residues of tebuconazole in wheat was detected by Waters 600 highperformance liquid chromatography(HPLC) with Ultraviolet absorptiondetector(UV). The recovery rates of 0.1mg/kg, 0.2mg/kg, 2.0 mg/kg threeconcentration of tebuconazole respectively was 86.00%±2.78, 89.21%±1.17,95.06%±3.58 in wheat stem &leaf and it was 80.00%±4.31, 83.66%±2.96,88.40%±2.62 in wheat ear.3. A residue analytical method was set up for analysis thiram in wheat.The residues of thiram in wheat was detected by Waters 600 high performanceliquid chromatography(HPLC) with Ultraviolet absorption detector(UV). Therecovery rates of different concentration of thiram in wheat stem&leaf were inabove 75%.4. A residue analytical method was set up for analysis tebuconazole andthiram admixture in wheat. The residues of tebuconazole and thiram admixturein wheat were detected by Waters 600 high performance liquidchromatography(HPLC) with Ultraviolet absorption detector(UV). Therecovery rates of different concentration of tebuconazole·thiram in wheatstem&leaf and ear were in above 75%. 5. The residued dynamics of tebuconazole, thiram and their admixture inwheat were studied by potted plant experiment and field expriment. Theresults of experiment show that the speed of degradation of tebuconazolethiram and their admixture in wheat were different when pesticides employedin different time and with different treatment. The degradation rate ofpesticides after spraying treatment were faster than that after dressing seedtreatment. After wheat was sprayed by pesticides, the degradation rate oftebuconazole and thiram respectively was similar with its in their admixture.After wheat seed was dressed with the pestcides, the degradation rate oftebuconazole in wheat was slightly faster than it in the 14% wheatseed-coating agent. However, the degradation rate of thiram in wheat rot wasgreatly faster than it in the 14% wheat seed-coating agent. The half-life of tebuconazole, thiram and their admixture in wheat andwheat rot with different treatments were as follows: (1) 3.9 days in wheatspraying with after 80g/hm2 20% tebuconzole WP, 5.6 days in wheat afterdressing seed with 0.03‰weight of seed 20% tebuconazole WP. (2) 3.2 daysin wheat after spraying with 80g/hm2 50% thiram WP, 9.9 days in wheat rotafter dressing seed with 50% thiram WP in the amount of 2.5‰weight ofseed. (3)tebuconazole: 4.0 days in wheat spraying with 80g/hm2 40%tebuconzole·thiram WP, 6.9 days in wheat after dressing seed with 14% wheatseed-coating agent in the amount of 1/50 pesticide/seed. Thiram: 3.0 days inwheat after spraying with 80g/hm2 40% tebuconzole·thiram WP, 6.2 days inwheat after dressing seed with 14% wheat seed-coating agent in the amount of1/50 pesticide/seed. 6. The terminal residue of tebuconzole, thiram and their admixture inwheat stem&leaf and wheat ear after spraying treatment in different...
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