Begg Graham S, Elliott Martin J, Cullen Danny W, Iannetta Pietro P M, Squire Geoff R
Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, UK.
Transgenic Res. 2008 Oct;17(5):805-16. doi: 10.1007/s11248-008-9166-7. Epub 2008 Feb 22.
The implementation of co-existence in the commercialisation of GM crops requires GM and non-GM products to be segregated in production and supply. However, maintaining segregation in oilseed rape will be made difficult by the highly persistent nature of this species. An understanding of its population dynamics is needed to predict persistence and develop potential strategies for control, while to ensure segregation is being achieved, the production of GM oilseed rape must be accompanied by the monitoring of GM levels in crop or seed populations. Heterogeneity in the spatial distribution of oilseed rape has the potential to affect both control and monitoring and, although a universal phenomenon in arable weeds and harvested seed lots, spatial heterogeneity in oilseed rape populations remains to be demonstrated and quantified. Here we investigate the distribution of crop and volunteer populations in a commercial field before and during the cultivation of the first conventional oilseed rape (winter) crop since the cultivation of a GM glufosinate-tolerant oilseed rape crop (spring) three years previously. GM presence was detected by ELISA for the PAT protein in each of three morphologically distinguishable phenotypes: autumn germinating crop-type plants (3% GM), autumn-germinating 'regrowths' (72% GM) and spring germinating 'small-type' plants (17% GM). Statistical models (Poisson log-normal and binomial logit-normal) were used to describe the spatial distribution of these populations at multiple spatial scales in the field and of GM presence in the harvested seed lot. Heterogeneity was a consistent feature in the distribution of GM and conventional oilseed rape. Large trends across the field (50 x 400 m) and seed lot (4 x 1.5 x 1.5 m) were observed in addition to small-scale heterogeneity, less than 20 m in the field and 20 cm in the seed lot. The heterogeneity was greater for the 'regrowth' and 'small' phenotypes, which were likely to be volunteers and included most of the GM plants detected, than for the largely non-GM 'crop' phenotype. The implications of the volunteer heterogeneity for field management and GM-sampling are discussed.
转基因作物商业化过程中实施共存要求转基因和非转基因产品在生产与供应环节进行隔离。然而，由于油菜具有高度持久的特性，在油菜中维持隔离将变得困难。需要了解其种群动态以预测持久性并制定潜在的控制策略，同时为确保实现隔离，转基因油菜的生产必须伴随对作物或种子群体中转基因水平的监测。油菜空间分布的异质性有可能影响控制和监测，尽管这在可耕地杂草和收获种子批次中是普遍现象，但油菜种群的空间异质性仍有待证明和量化。在此，我们调查了自三年前种植转基因抗草铵膦油菜（春季）以来，首个常规油菜（冬季）作物种植前和种植期间一块商业田地中作物和自生苗群体的分布情况。通过酶联免疫吸附测定法（ELISA）检测了三种形态上可区分表型中每种表型的PAT蛋白以确定转基因的存在：秋季萌发的作物型植株（3%为转基因）、秋季萌发的“再生苗”（72%为转基因）和春季萌发的“小型”植株（17%为转基因）。使用统计模型（泊松对数正态和二项式对数正态）来描述这些群体在田间多个空间尺度上的空间分布以及收获种子批次中转基因存在情况。异质性是转基因和常规油菜分布的一个一致特征。除了小于20米的田间小尺度异质性和小于20厘米的种子批次小尺度异质性外，还观察到了整个田地（50×400米）和种子批次（4×1.5×1.5米）的大趋势。“再生苗”和“小型”表型的异质性更大，它们可能是自生苗且包含了检测到的大部分转基因植株，而“作物”表型大部分是非转基因的，其异质性较小。文中讨论了自生苗异质性对田间管理和转基因采样的影响。
