Phosphine fumigation trials were carried out on bag-stacks of paddy rice to study the differences in gas loss rates and concentration-time (Ct) products achieved during the treatment of indoor and outdoor stacks. Stacks (89-132t) were fumigated singly under 250&mgr;m thick polyethylene sheeting, which was sealed with a double layer of sand-snakes to the concrete floor. Phosphine was applied as an aluminium phosphide formulation and the fumigations continued for 7 days. In the first experiment, stacks of paddy rice with moisture contents ranging from 12.2 to 13.7% were held in either indoor or in outdoor storage and subjected to fumigation at the rate of 2, 3 or 4g of phosphine/tonne. The outdoor stacks held relatively low levels of phosphine with Ct products for the indoor stacks of 135, 171 and 294gh/m(3), respectively, whilst the corresponding values for the outdoor stacks were 70, 85 and 166gh/m(3) only. The average gas loss rate was 14.5% per day for the indoor stacks and 29.5% for the outdoor stacks. In the second experiment, old stacks of paddy rice inside a godown, one each with grains at 8.8 and 9.8% moisture content, were fumigated at 3g phosphine/tonne. Release of phosphine was delayed and fumigant sorption was less and therefore higher Ct products of 204 and 216gh/m(3) were achieved. In the stacks built outdoors, the resident infestations of Rhyzopertha dominica, Cryptolestes sp. and Oryzaephilus surinamensis were completely controlled despite lower Ct products. On the other hand, in the stacks of old paddy, R. dominica survived the treatment. Subsequent testing showed that the population had a degree of resistance to phosphine.

中文翻译：

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磷化氢在室内外商店袋装水稻熏蒸中的性能

磷化氢熏蒸试验是在稻谷袋堆上进行的，以研究处理室内和室外稻谷时气体损失率和浓度-时间 (Ct) 产品的差异。堆栈（89-132t）在250μm厚的聚乙烯板下单独熏蒸，用双层沙蛇密封在混凝土地板上。磷化氢以磷化铝制剂形式施用，熏蒸持续 7 天。在第一个实验中，将含水量在 12.2% 至 13.7% 之间的稻谷堆放在室内或室外储存，并以 2、3 或 4 克磷化氢/吨的比率进行熏蒸。室外烟囱的磷化氢含量相对较低，室内烟囱的 Ct 产品分别为 135、171 和 294 gh/m(3)，而室外烟囱的相应值仅为 70、85 和 166gh/m(3)。室内烟囱的平均气体损失率为每天 14.5%，室外烟囱为 29.5%。在第二个实验中，仓库内的旧稻谷堆以 3 克磷化氢/吨熏蒸，每堆稻谷的水分含量为 8.8% 和 9.8%。磷化氢的释放被延迟，熏蒸剂的吸附较少，因此实现了 204 和 216gh/m(3) 的更高 Ct 产品。在户外建造的烟囱中，多米尼加根霉的居民侵扰，Cryptolestes sp。尽管 Ct 值较低，但 Oryzaephilus surinamensis 被完全控制。另一方面，在成堆的老稻田中，R. dominica 幸免于难。随后的测试表明，该种群对磷化氢具有一定程度的抵抗力。