Phillips C B, Iline I I, Novoselov M, McNeill M R, Richards N K, van Koten C, Stephenson B P
AgResearch, Lincoln, Private Bag 4749, Canterbury, 8140 New Zealand.
Ministry for Primary Industries, PO Box 2526, Wellington, 6140 New Zealand.
J Pest Sci (2004). 2015;88(1):121-134. doi: 10.1007/s10340-014-0573-7. Epub 2014 Mar 7.
Live organisms intercepted from treated commodities during phytosanitary inspections usually arouse suspicions of treatment failure, sub-standard treatment application, or post-treatment infestation. The additional possibility that some treatments could kill slowly, meaning commodities might be inspected before pests have succumbed, is seldom considered for treatments other than irradiation. We used a novel biochemical viability assay to measure delays between methyl bromide fumigation and mortality of dipteran eggs, and evaluated the correspondence between egg viability and egg morphological features. Our experimental conditions simulated shipping of rock melons from Australia to New Zealand by sea and air. No eggs survived fumigation, but they took 3-20 days to die, whereas phytosanitary inspections of rock melons occur within 2-7 days. Delays were not influenced by methyl bromide concentration, but were significantly lengthened by cooler storage temperatures. Methyl bromide's preservative effects delayed degradation of egg morphology, so the biochemical assay detected mortality long before morphological signs of egg death appeared. The results show that commodities subjected to effective methyl bromide treatments are at risk of being inspected before all pests have either died, or started to exhibit morphological signs of death. This could cause commodities to be unnecessarily rejected by quarantine authorities. Better methods than inspection for live pests are needed to assist authorities to gain assurance that treated commodities have been effectively disinfested. These could be developed by exploiting biochemical responses of pests and commodities to treatments.
在植物检疫检查期间，从经过处理的商品中截获的活生物体通常会引发对处理失败、处理应用不达标或处理后感染的怀疑。除辐照外，很少考虑其他处理方法存在的另一种可能性，即某些处理可能会缓慢致死，这意味着在害虫死亡之前商品可能就已接受检查。我们使用一种新型生化活力测定法来测量溴甲烷熏蒸与双翅目昆虫卵死亡之间的延迟，并评估卵活力与卵形态特征之间的对应关系。我们的实验条件模拟了从澳大利亚通过海运和空运向新西兰运输哈密瓜的情况。熏蒸后没有卵存活，但它们需要3至20天才能死亡，而对哈密瓜的植物检疫检查在2至7天内进行。延迟不受溴甲烷浓度的影响，但在较低的储存温度下会显著延长。溴甲烷的防腐作用延迟了卵形态的降解，因此生化测定法在卵死亡的形态学迹象出现之前很久就能检测到死亡情况。结果表明，经过有效溴甲烷处理的商品有风险在所有害虫死亡或开始出现死亡形态迹象之前就接受检查。这可能导致商品被检疫当局不必要地拒收。需要比检查活害虫更好的方法来帮助当局确信经过处理的商品已得到有效除害。这可以通过利用害虫和商品对处理的生化反应来开发。
